XC90 2011 R-Design ABS fault

Paul5690 · Jul 1st, 2018, 19:58

Good evening,

Sorry if this has been posted before but I’m hoping someone can help me with problems I’m having with my Volvo XC90 2011, R-design, 2.4 diesel, D5.

Last week my wife was driving the car and the ABS light came on and warning saying, Break failed stop safely. The Speedo works, however it says adaptive headlight service required, the ABS light is on, the odometer is not working and it won’t let me know how many miles is left till fuel empty.

I’m in the U.K. military and currently serving in Cyprus. I brought the car in the U.K. and shipped it with me. When we plugged it into a computer it said code P0722, no reading from Speed sensor. I have taken it to a garage here and they have said that it looks like the ECM is at fault and wanted £750 to try and fix it or £1500 for a new one, a lot more than the U.K.

My question is does this sound right? I have been looking through the forums and some people point towards a faulty BCM?

If it is a faulty ECM or BCM what are my realistic options? I’m happy to buy a new one when I return to U.K. next week with work, however this is a lot of money if it’s not the problem? Can they be fixed or is it possible to buy second hand? I have looked on forums and some people say second had from the same year and model etc could work?

Thanks in advance for your help.

AidanC · Jul 1st, 2018, 22:23

Not sure if you had had the car read with Vida or a generic ODBC code reader but I suspect a generic code reader. You'll get a lot more info from Vida. If you're going to spend money and the codes haven't been read with Vida, either have a local Volvo dealer run a diagnosis or get a Vida setup in the UK to bring back with you. It sounds a bit vague in terms of diagnosis at the moment so a definite diagnosis will likely save you money. There are examples on this forum of loose connections creating noise on the local network and triggering false error codes so that should be taken into account once you've some info from Vida.

Clan · Jul 1st, 2018, 22:29

Quote:

Originally Posted by Paul5690

Good evening,

Sorry if this has been posted before but I’m hoping someone can help me with problems I’m having with my Volvo XC90 2011, R-design, 2.4 diesel, D5.

Last week my wife was driving the car and the ABS light came on and warning saying, Break failed stop safely. The Speedo works, however it says adaptive headlight service required, the ABS light is on, the odometer is not working and it won’t let me know how many miles is left till fuel empty.

I’m in the U.K. military and currently serving in Cyprus. I brought the car in the U.K. and shipped it with me. When we plugged it into a computer it said code P0722, no reading from Speed sensor. I have taken it to a garage here and they have said that it looks like the ECM is at fault and wanted £750 to try and fix it or £1500 for a new one, a lot more than the U.K.

My question is does this sound right? I have been looking through the forums and some people point towards a faulty BCM?

If it is a faulty ECM or BCM what are my realistic options? I’m happy to buy a new one when I return to U.K. next week with work, however this is a lot of money if it’s not the problem? Can they be fixed or is it possible to buy second hand? I have looked on forums and some people say second had from the same year and model etc could work?

Thanks in advance for your help.

the speedo uses signals from the ABS Sensors , left front I believe , your fault is probably an ABS toothed ring around a driveshaft split . A relatively cheap cost .. Best get your dealer to read the codes properly , it will probably say a mechanical fault with left front ABS Sender /

SwissXC90 · Jul 2nd, 2018, 05:43

Whatever you do, do not buy parts based on guesswork

A lot of control modules for the car need to be programmed to the car to make them work: buying 2nd hand ones won't help you, and buying new modules which are not programmed won't help you.
The programming is done at a Volvo dealer using VIDA

Luckily there is a Volvo on Cyprus (I've been there, I know how "end of the world" it appears to be) and for such a fault you are better off going fdirect to Volvo as they have VIDA and can diagnose it properly

You need to confirm all 4 wheels are sending their speed pulses to the BCM (brake control module).
This can be done many ways, one way is put the car on a lift, and spin each wheel in turn, whilst monitoring the speed sensor signal wire with an oscilloscope to look at the waveform. This will very quickly show you if all wheels are good.
Another way is look at the data in VIDA, easy to do, it shows live data from each wheel

All your symptoms indicate that it is likely a bad wheel ABS sensor of more likely the ABS reluctor ring. If a ring, it is easy to spot (look for physical damage like cracks and too much rust) and cheap to replace, and can be done by a non-Volvo garage. Even if not sure, replacing a bad looking ABS reluctor ring is not a bad piece of preventative maintenance, as they are very cheap each.

The ABS sensors are connected directly to the Brake Control Module (BCM) and the BCM sends the wheel speed data to the rest of the vehicle via the CAN bus.
So anything that needs wheel speed data, such as speedo, odometer, ABS, active bending headlights, etc will not work when no speed data is present.

VIDA will show the speed data from each wheel
A good diagnostic tool may be able to show it as well.

Start with the front wheels first when inspecting the ABS sensors, as corrosion and damage is more likely at the front then at the rear.

If all 4 wheel sensors are confirmed good, then unfortunately you may have a faulty BCM module. Replacing the BCM requires coding. And as it is part of the ABS system you do want to ensure it is operating properly.
This may mean you need to take your vehicle a local Volvo dealer, these guys seem to have a good reputation:
CTC Automotive Ltd
Arch. Makarios III Avenue, Limassol, Cyprus
+357 25 388222

Paul5690 · Jul 2nd, 2018, 18:55

This is really great advice, thank you all.

I would like to start by inspecting the ABS reluctor ring, you say that it’s easy to spot if they are damaged. Is there a easy way to see these or do I have to strip things down to get access. I am happy doing work to cars so any advice on looking into this would be great. Hopefully this is the problem.

Failing that I will take it to the Volvo dealer to get a VIDA check done. If it is the BCM I would probably look at getting one from the U.K. where things are cheaper and get it programmed in Cyprus?

Just a final point, when this problem come to light the power steering on the car became more stiff, would this be related or would a flush of the power steering fluid maybe fix this. There are no sounds or coming from the starring, fluid is correct level, no leaks but the fluid has not been changed for a number of years!

Again thanks for your help all, hopefully I can get to the bottom of this without too much pin or cost!

SwissXC90 · Jul 2nd, 2018, 20:28

Quote:

Originally Posted by Paul5690

Just a final point, when this problem come to light the power steering on the car became more stiff, would this be related or would a flush of the power steering fluid maybe fix this. There are no sounds or coming from the starring, fluid is correct level, no leaks but the fluid has not been changed for a number of years!

The R-Design has a speed-sensitive power steering.

Thus it makes sense that if the vehicle has lost the speed information, that the power steering goes into whatever default mode it has.

So don't worry about the steering yet.
Fix the speed sensor problem first.
The steering will likely be OK afterwards.

SwissXC90 · Jul 2nd, 2018, 20:29

This may help you (from VIDA)

Wheel sensors

There are four wheel sensors, one at each wheel. The wheel sensors supply the control module with information about the rotation speed, acceleration and retardation of each wheel. By recording the pulses, the control module can calculate the wheel speed.

The wheel sensors are active sensors. When the pulse wheel rotates, the sensor generates a pulsed current (quadratic wave) where the strength of the current depends on the position of the pulse wheel. The signals from the coils in the wheel sensors are then affected by a magnetic resistance element, which generates a current which changes between 7mA and 14mA, and whose frequency increases with speed.

On the front wheels, the pulse wheel is pressed onto the outer constant velocity joint and the wheel sensors are located radially in the shaft housing relative to the pulse wheel. On the rear wheels, the pulse wheel is pressed onto the hub and the wheel sensors are located axially relative to the pulse wheel. Both the front and rear pulse wheels have 48 teeth. In the event of a fault in any of the wheel sensors the following systems will be disengaged or will not engage:

ABS
TRACS
STC
DSTC/ESC

Electronic brake force distribution (EBD) is available if one wheel sensor is faulty. Electronic brake force distribution (EBD) is disengaged if there is a fault in more than one wheel sensor simultaneously.

The control module calculates the vehicle speed using the signals from the wheel sensors. There are diagnostics for the wheel sensors.

SwissXC90 · Jul 2nd, 2018, 20:32

And VIDA even has a rudimentary testing procedure:

A14 #14 Wheel sensor left front, signal output. Tooth at sensor
U≈Ulow
Cover at sensor
U≈Ubat Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #14. Connect a voltmeter between #14 and ground connection #16. Turn the wheel slowly.

The pin numbers # are on the BCM connector

Here are the BCM signals and pins

Breakout box terminal Terminal ECU Signal type Ignition on Miscellaneous
#A1 #1 30-supply pump motor (power supply from battery) U = Ubat With a 30 A fuse.
#A2 #2 Diagnostic lead C-link - -
#A3 #3 Pedal position sensor, signal 0-5 V Brake pedal position, analog signal.
0 mm: ≈0 V
38.5 mm: ≈ 95% of 5 V
#A4 #4 15-supply (power supply from the ignition switch) U = Ubat -
#A5 #5 Pedal position sensor, signal ground U=Ulow -
#A6 #6 Active yaw control sensor, power supply U = Ubat The active yaw control sensor receives 12 V from the control module.
#A7 #7 Pedal position sensor, power supply U =5 V The pedal position sensor receives 5 V from the control module.
#A8 #8 Wheel sensor right rear, signal output. Tooth at sensor
U≈Ulow
Cover at sensor
U≈Ubat Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #8. Connect a voltmeter between #8 and ground connection #16. Turn the wheel slowly.
#A9 #9 - - -
#A10 #10 Wheel sensor left rear, signal output. Tooth at sensor
U≈Ulow
Cover at sensor
U≈Ubat Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #10. Connect a voltmeter between #10 and ground connection #16. Turn the wheel slowly.
#A11 #11 Control modules communication cable (CAN H) U=2-3 V -
#A12 #12 Wheel sensor right front, signal output. Tooth at sensor
U≈Ulow
Cover at sensor
U≈Ubat Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #12. Connect a voltmeter between #12 and ground connection #16. Turn the wheel slowly.
#A13 #13 - - -
#A14 #14 Wheel sensor left front, signal output. Tooth at sensor
U≈Ulow
Cover at sensor
U≈Ubat Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #14. Connect a voltmeter between #14 and ground connection #16. Turn the wheel slowly.
#A15 #15 Control modules communication cable (CAN L) U=2-3 V -
#A16 #16 Power and signal ground U=Ulow Ground terminal for the input and outlet valves and signal to the control module.
#A17 #17 Pressure build-up valve, power supply. U=4.75-5.25 V -
#A18 #18 Brake pressure sensor 2 (B), voltage-feed U=4.75-5.25 V Due to possibility of incorrect installation,#18-#20 may also be Brake pressure sensor 1 (A).
#A19 #19 Brake pressure sensor 2 (B), signal ground U=Ulow -
#A20 #20 Brake pressure sensor 2 (B), signal U=0.25-4.75 V Analog signal
0-170 bar
23 mV/bar
0 bar = 0.5 V
#A21 #21 Brake pressure sensor 1 (A), signal ground. U=Ulow Due to possibility of incorrect installation,#21-#23 may also be Brake pressure sensor 2 (B).
#A22 #22 Brake pressure sensor 1 (A), voltage-feed. U=4.75-5.25 V -
#A23 #23 Brake pressure sensor 1 (A), signal U=0.25-4.75 V Analog signal
0-170 bar
23 mV/bar
0 bar = 0.5 V
#A24 #24 - - -
#A25 #25 Active yaw control sensor, communication cable (CAN L) U=2-3 V -
#A26 #26 - - -
#A27 #27 Pedal pressure switch, signal Open: U≈Ulow
Closed: U ≈Ubat The pedal pressure switch is open when the brake pedal is depressed.
#A28 #28 Test signal for the pedal pressure switch - -
#A29 #29 Active yaw control sensor, communication cable (CAN H) U=2-3 V -
#A30 #30 Pedal pressure switch, signal The pedal pressure switch is closed when the brake pedal is not pressed.
#A31 #31 Pressure build-up valve, power supply 12 V Pulse width modulated signal:
maximum 4A
18kHz
#A32 #32 30-supply for the valves (power supply from battery) U = Ubat With a 30 A fuse.
#A33 #33 Front right wheel sensor. signal Tooth against sensor:
I≈14 mA
Cover against sensor:
I ≈ 7 mA The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed.
For test of sensor's function, see #12
#A34 #34 Front right wheel sensor, power supply. U = Ubat The wheel sensor receives 12 V from the control module.
#A35 #35 - - -
#A36 #36 Rear left wheel sensor, power supply. U = Ubat The wheel sensor receives 12 V from the control module.
#A37 #37 Rear left wheel sensor, signal Tooth against sensor:
I≈14 mA
Cover against sensor:
I ≈ 7 mA The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed.
For test of sensor's function, see #10 in the table
#A38 #38 - - -
#A39 #39 Active yaw control sensor, ground U=Ulow -
#A40 #40 - - -
#A41 #41 - - -
#A42 #42 Rear right wheel sensor, signal Tooth against sensor:
I≈14 mA
Cover against sensor:
I ≈ 7 mA The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed.
For test of sensor's function, see #8 in the table
#A43 #43 Right rear wheel sensor, power supply U = Ubat The wheel sensor receives 12 V from the control module.
#A44 #44 - - -
#A45 #45 Front left wheel sensor, power supply U = Ubat The wheel sensor receives 12 V from the control module.
#A46 #46 Front left wheel sensor, signal Tooth against sensor:
I≈14 mA
Cover against sensor:
I ≈ 7 mA The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed.
For test of sensor's function, see #14 in the table
#A47 #47 Power and signal ground U=Ulow Ground terminal for the pump motor.

dstc · Jul 6th, 2018, 13:21

Easily done. Get under the car. You'll need a torch. You can either jack the car up with the transmission in Neutral so you can spin the front wheel and look for a crack in the ABS ring. You're looking at the back of the hub, with all the suspension arms up and infront of you. It's fitted in a groove around the driveshaft (at the hub end not the gearbox). If your driveway is long enough you'll have to keep moving the car forward and popping under so you can see check the teeth.

Paul5690 · Aug 9th, 2018, 15:28

Hi, so checked the ABS rings and these are fine.

Visited Volvo Cyprus and they ran diagnostics and the Break control module is not responding. This week they have tried to fit the BCM and the car won’t go into program mode. They have said that the radio/Bluetooth module won’t go into program mode so they can’t program the new BCM!

Same faults. ABS lights on, odometer not adding miles, stiff power steering, adaptive headlights not working, trip computer not working. Can use the car as we have done waiting for new part.

Is it a case that the BCM could be ok it’s another fault or is something else going on that won’t let it program?

Thanks for all the good advice it’s been very helpful.

Jul 1st, 2018, 19:58	#1
Paul5690 New Member Last Online: May 14th, 2020 17:24 Join Date: Jul 2018 Location: Uxbridge	XC90 2011 R-Design ABS fault Good evening, Sorry if this has been posted before but I’m hoping someone can help me with problems I’m having with my Volvo XC90 2011, R-design, 2.4 diesel, D5. Last week my wife was driving the car and the ABS light came on and warning saying, Break failed stop safely. The Speedo works, however it says adaptive headlight service required, the ABS light is on, the odometer is not working and it won’t let me know how many miles is left till fuel empty. I’m in the U.K. military and currently serving in Cyprus. I brought the car in the U.K. and shipped it with me. When we plugged it into a computer it said code P0722, no reading from Speed sensor. I have taken it to a garage here and they have said that it looks like the ECM is at fault and wanted £750 to try and fix it or £1500 for a new one, a lot more than the U.K. My question is does this sound right? I have been looking through the forums and some people point towards a faulty BCM? If it is a faulty ECM or BCM what are my realistic options? I’m happy to buy a new one when I return to U.K. next week with work, however this is a lot of money if it’s not the problem? Can they be fixed or is it possible to buy second hand? I have looked on forums and some people say second had from the same year and model etc could work? Thanks in advance for your help.

Jul 1st, 2018, 22:23	#2
AidanC Senior Member Last Online: Jul 6th, 2024 20:10 Join Date: Jun 2007 Location: Kildare	Not sure if you had had the car read with Vida or a generic ODBC code reader but I suspect a generic code reader. You'll get a lot more info from Vida. If you're going to spend money and the codes haven't been read with Vida, either have a local Volvo dealer run a diagnosis or get a Vida setup in the UK to bring back with you. It sounds a bit vague in terms of diagnosis at the moment so a definite diagnosis will likely save you money. There are examples on this forum of loose connections creating noise on the local network and triggering false error codes so that should be taken into account once you've some info from Vida. __________________ My Volvos: '67 Amazon 131 '12 XC90 D5 SE Lux Last edited by AidanC; Jul 1st, 2018 at 22:35.

Jul 2nd, 2018, 05:43	#4
SwissXC90 Premier Member Last Online: Mar 20th, 2024 18:26 Join Date: Jan 2016 Location: Cross Country	Whatever you do, do not buy parts based on guesswork A lot of control modules for the car need to be programmed to the car to make them work: buying 2nd hand ones won't help you, and buying new modules which are not programmed won't help you. The programming is done at a Volvo dealer using VIDA Luckily there is a Volvo on Cyprus (I've been there, I know how "end of the world" it appears to be) and for such a fault you are better off going fdirect to Volvo as they have VIDA and can diagnose it properly You need to confirm all 4 wheels are sending their speed pulses to the BCM (brake control module). This can be done many ways, one way is put the car on a lift, and spin each wheel in turn, whilst monitoring the speed sensor signal wire with an oscilloscope to look at the waveform. This will very quickly show you if all wheels are good. Another way is look at the data in VIDA, easy to do, it shows live data from each wheel All your symptoms indicate that it is likely a bad wheel ABS sensor of more likely the ABS reluctor ring. If a ring, it is easy to spot (look for physical damage like cracks and too much rust) and cheap to replace, and can be done by a non-Volvo garage. Even if not sure, replacing a bad looking ABS reluctor ring is not a bad piece of preventative maintenance, as they are very cheap each. The ABS sensors are connected directly to the Brake Control Module (BCM) and the BCM sends the wheel speed data to the rest of the vehicle via the CAN bus. So anything that needs wheel speed data, such as speedo, odometer, ABS, active bending headlights, etc will not work when no speed data is present. VIDA will show the speed data from each wheel A good diagnostic tool may be able to show it as well. Start with the front wheels first when inspecting the ABS sensors, as corrosion and damage is more likely at the front then at the rear. If all 4 wheel sensors are confirmed good, then unfortunately you may have a faulty BCM module. Replacing the BCM requires coding. And as it is part of the ABS system you do want to ensure it is operating properly. This may mean you need to take your vehicle a local Volvo dealer, these guys seem to have a good reputation: CTC Automotive Ltd Arch. Makarios III Avenue, Limassol, Cyprus +357 25 388222 __________________ XC90 R-Design MY2009, Black Sapphire Metallic. HP-Sound, RSE, Nav, Tel, ParkingCam, BLIS, ParkingHeater, RestHeat, Removable Towbar, Summer: CRATUS 20x8 on Pirelli Scorpion Zeros 255/45, Winter: NEPTUNE 17x7 on Continental WinterContact 4x4 235/65.

Jul 2nd, 2018, 18:55	#5
Paul5690 New Member Last Online: May 14th, 2020 17:24 Join Date: Jul 2018 Location: Uxbridge	This is really great advice, thank you all. I would like to start by inspecting the ABS reluctor ring, you say that it’s easy to spot if they are damaged. Is there a easy way to see these or do I have to strip things down to get access. I am happy doing work to cars so any advice on looking into this would be great. Hopefully this is the problem. Failing that I will take it to the Volvo dealer to get a VIDA check done. If it is the BCM I would probably look at getting one from the U.K. where things are cheaper and get it programmed in Cyprus? Just a final point, when this problem come to light the power steering on the car became more stiff, would this be related or would a flush of the power steering fluid maybe fix this. There are no sounds or coming from the starring, fluid is correct level, no leaks but the fluid has not been changed for a number of years! Again thanks for your help all, hopefully I can get to the bottom of this without too much pin or cost!

Jul 2nd, 2018, 20:29	#7
SwissXC90 Premier Member Last Online: Mar 20th, 2024 18:26 Join Date: Jan 2016 Location: Cross Country	This may help you (from VIDA) Wheel sensors There are four wheel sensors, one at each wheel. The wheel sensors supply the control module with information about the rotation speed, acceleration and retardation of each wheel. By recording the pulses, the control module can calculate the wheel speed. The wheel sensors are active sensors. When the pulse wheel rotates, the sensor generates a pulsed current (quadratic wave) where the strength of the current depends on the position of the pulse wheel. The signals from the coils in the wheel sensors are then affected by a magnetic resistance element, which generates a current which changes between 7mA and 14mA, and whose frequency increases with speed. On the front wheels, the pulse wheel is pressed onto the outer constant velocity joint and the wheel sensors are located radially in the shaft housing relative to the pulse wheel. On the rear wheels, the pulse wheel is pressed onto the hub and the wheel sensors are located axially relative to the pulse wheel. Both the front and rear pulse wheels have 48 teeth. In the event of a fault in any of the wheel sensors the following systems will be disengaged or will not engage: ABS TRACS STC DSTC/ESC Electronic brake force distribution (EBD) is available if one wheel sensor is faulty. Electronic brake force distribution (EBD) is disengaged if there is a fault in more than one wheel sensor simultaneously. The control module calculates the vehicle speed using the signals from the wheel sensors. There are diagnostics for the wheel sensors. __________________ XC90 R-Design MY2009, Black Sapphire Metallic. HP-Sound, RSE, Nav, Tel, ParkingCam, BLIS, ParkingHeater, RestHeat, Removable Towbar, Summer: CRATUS 20x8 on Pirelli Scorpion Zeros 255/45, Winter: NEPTUNE 17x7 on Continental WinterContact 4x4 235/65.

Jul 2nd, 2018, 20:32	#8
SwissXC90 Premier Member Last Online: Mar 20th, 2024 18:26 Join Date: Jan 2016 Location: Cross Country	And VIDA even has a rudimentary testing procedure: A14 #14 Wheel sensor left front, signal output. Tooth at sensor U≈Ulow Cover at sensor U≈Ubat Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #14. Connect a voltmeter between #14 and ground connection #16. Turn the wheel slowly. The pin numbers # are on the BCM connector Here are the BCM signals and pins Breakout box terminal Terminal ECU Signal type Ignition on Miscellaneous #A1 #1 30-supply pump motor (power supply from battery) U = Ubat With a 30 A fuse. #A2 #2 Diagnostic lead C-link - - #A3 #3 Pedal position sensor, signal 0-5 V Brake pedal position, analog signal. 0 mm: ≈0 V 38.5 mm: ≈ 95% of 5 V #A4 #4 15-supply (power supply from the ignition switch) U = Ubat - #A5 #5 Pedal position sensor, signal ground U=Ulow - #A6 #6 Active yaw control sensor, power supply U = Ubat The active yaw control sensor receives 12 V from the control module. #A7 #7 Pedal position sensor, power supply U =5 V The pedal position sensor receives 5 V from the control module. #A8 #8 Wheel sensor right rear, signal output. Tooth at sensor U≈Ulow Cover at sensor U≈Ubat Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #8. Connect a voltmeter between #8 and ground connection #16. Turn the wheel slowly. #A9 #9 - - - #A10 #10 Wheel sensor left rear, signal output. Tooth at sensor U≈Ulow Cover at sensor U≈Ubat Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #10. Connect a voltmeter between #10 and ground connection #16. Turn the wheel slowly. #A11 #11 Control modules communication cable (CAN H) U=2-3 V - #A12 #12 Wheel sensor right front, signal output. Tooth at sensor U≈Ulow Cover at sensor U≈Ubat Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #12. Connect a voltmeter between #12 and ground connection #16. Turn the wheel slowly. #A13 #13 - - - #A14 #14 Wheel sensor left front, signal output. Tooth at sensor U≈Ulow Cover at sensor U≈Ubat Measure by creating a temporary voltage supply between #1 via a resistance of 1kΩ and #14. Connect a voltmeter between #14 and ground connection #16. Turn the wheel slowly. #A15 #15 Control modules communication cable (CAN L) U=2-3 V - #A16 #16 Power and signal ground U=Ulow Ground terminal for the input and outlet valves and signal to the control module. #A17 #17 Pressure build-up valve, power supply. U=4.75-5.25 V - #A18 #18 Brake pressure sensor 2 (B), voltage-feed U=4.75-5.25 V Due to possibility of incorrect installation,#18-#20 may also be Brake pressure sensor 1 (A). #A19 #19 Brake pressure sensor 2 (B), signal ground U=Ulow - #A20 #20 Brake pressure sensor 2 (B), signal U=0.25-4.75 V Analog signal 0-170 bar 23 mV/bar 0 bar = 0.5 V #A21 #21 Brake pressure sensor 1 (A), signal ground. U=Ulow Due to possibility of incorrect installation,#21-#23 may also be Brake pressure sensor 2 (B). #A22 #22 Brake pressure sensor 1 (A), voltage-feed. U=4.75-5.25 V - #A23 #23 Brake pressure sensor 1 (A), signal U=0.25-4.75 V Analog signal 0-170 bar 23 mV/bar 0 bar = 0.5 V #A24 #24 - - - #A25 #25 Active yaw control sensor, communication cable (CAN L) U=2-3 V - #A26 #26 - - - #A27 #27 Pedal pressure switch, signal Open: U≈Ulow Closed: U ≈Ubat The pedal pressure switch is open when the brake pedal is depressed. #A28 #28 Test signal for the pedal pressure switch - - #A29 #29 Active yaw control sensor, communication cable (CAN H) U=2-3 V - #A30 #30 Pedal pressure switch, signal The pedal pressure switch is closed when the brake pedal is not pressed. #A31 #31 Pressure build-up valve, power supply 12 V Pulse width modulated signal: maximum 4A 18kHz #A32 #32 30-supply for the valves (power supply from battery) U = Ubat With a 30 A fuse. #A33 #33 Front right wheel sensor. signal Tooth against sensor: I≈14 mA Cover against sensor: I ≈ 7 mA The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed. For test of sensor's function, see #12 #A34 #34 Front right wheel sensor, power supply. U = Ubat The wheel sensor receives 12 V from the control module. #A35 #35 - - - #A36 #36 Rear left wheel sensor, power supply. U = Ubat The wheel sensor receives 12 V from the control module. #A37 #37 Rear left wheel sensor, signal Tooth against sensor: I≈14 mA Cover against sensor: I ≈ 7 mA The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed. For test of sensor's function, see #10 in the table #A38 #38 - - - #A39 #39 Active yaw control sensor, ground U=Ulow - #A40 #40 - - - #A41 #41 - - - #A42 #42 Rear right wheel sensor, signal Tooth against sensor: I≈14 mA Cover against sensor: I ≈ 7 mA The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed. For test of sensor's function, see #8 in the table #A43 #43 Right rear wheel sensor, power supply U = Ubat The wheel sensor receives 12 V from the control module. #A44 #44 - - - #A45 #45 Front left wheel sensor, power supply U = Ubat The wheel sensor receives 12 V from the control module. #A46 #46 Front left wheel sensor, signal Tooth against sensor: I≈14 mA Cover against sensor: I ≈ 7 mA The sensor generates a pulsed signal (quadratic wave) with a fixed pulse ratio when the pulse wheel rotates. The frequency increases with speed. For test of sensor's function, see #14 in the table #A47 #47 Power and signal ground U=Ulow Ground terminal for the pump motor. __________________ XC90 R-Design MY2009, Black Sapphire Metallic. HP-Sound, RSE, Nav, Tel, ParkingCam, BLIS, ParkingHeater, RestHeat, Removable Towbar, Summer: CRATUS 20x8 on Pirelli Scorpion Zeros 255/45, Winter: NEPTUNE 17x7 on Continental WinterContact 4x4 235/65.

Jul 6th, 2018, 13:21	#9
dstc Junior Member Last Online: Nov 28th, 2019 13:21 Join Date: Sep 2013 Location: London	Check the ABS ring Easily done. Get under the car. You'll need a torch. You can either jack the car up with the transmission in Neutral so you can spin the front wheel and look for a crack in the ABS ring. You're looking at the back of the hub, with all the suspension arms up and infront of you. It's fitted in a groove around the driveshaft (at the hub end not the gearbox). If your driveway is long enough you'll have to keep moving the car forward and popping under so you can see check the teeth.

Aug 9th, 2018, 15:28	#10
Paul5690 New Member Last Online: May 14th, 2020 17:24 Join Date: Jul 2018 Location: Uxbridge	Hi, so checked the ABS rings and these are fine. Visited Volvo Cyprus and they ran diagnostics and the Break control module is not responding. This week they have tried to fit the BCM and the car won’t go into program mode. They have said that the radio/Bluetooth module won’t go into program mode so they can’t program the new BCM! Same faults. ABS lights on, odometer not adding miles, stiff power steering, adaptive headlights not working, trip computer not working. Can use the car as we have done waiting for new part. Is it a case that the BCM could be ok it’s another fault or is something else going on that won’t let it program? Thanks for all the good advice it’s been very helpful.

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