V70: Electrical Alarm disable?

[ShadeTek]

My bonnet alarm switch is randomly going open circuit and tripping the alarm Is there any way of locking the car without having the alarm activated till I get to the switch?

[Martin Cox]

It may be easiest to simply bypass the bonnet switch until you can take a look at it. This is what I've done on my 2008 V70 for exactly the same reason.

There's a connector for the switch somewhere near the right hand bonnet latch. it's not too difficult to find. You can unplug it and I simply bridged the contacts in the connector with a suitable piece of wire held in place with some tape.

The down side is that you no longer get an indication if the bonnet is open.

I really must get around to looking at that switch some time but it is a bit of a pig to get at.

Martin

[ShadeTek]

My need is urgent so for just now I will try leaving the bonnet ajar so the alarm cannot activate!

[ShadeTek]

I got back from the pub last night after frantic phone calls form my missus about noising up the neighbourhood etc etc. However, all was quiet and the alarm was set so I let it lie overnight with no rude awakenings thankfully.

The switch looks boxed in tight and really awkward to get to as it is under the slam panel, behind the grill but also behind all the radiators and such too. I might be able to get to it if I take the headlight out? Job for tomorrow. I could look up the schematic and trace it back to where it goes and temporarliy ground that to trick the alarm into thinking the bonnet is shut. Of course it may not be the switch, lots of assuming here but more than likely, or even chaffed wiring or green boogers on a connector.

[Tatsfield]

I had exactly this problem:

You can spoof the circuit to accept the bonnet is closed using a paper clip cut into a "U" shape as a jumper across the contacts in the latch switch connector while you allow penetrating fluid to slowly work its way in and free up the seized action. Put insulating tape around the exposed bend part that protrudes to avoid any short circuit with the bodywork. See: https://www.volvoforums.org.uk/showthread.php?t=279884 for more information.

Having left the jumper clip in place with the penetrating fluid of a week or so, remove it to text whether the mechanism has freed it self, if not repeat until it does or until you give up and just leave the jumper there (Or replace the switch )

[ShadeTek]

Originally Posted by Tatsfield

I had exactly this problem:

You can spoof the circuit to accept the bonnet is closed using a paper clip cut into a "U" shape as a jumper across the contacts in the latch switch connector while you allow penetrating fluid to slowly work its way in and free up the seized action. Put insulating tape around the exposed bend part that protrudes to avoid any short circuit with the bodywork. See: https://www.volvoforums.org.uk/showthread.php?t=279884 for more information.

Having left the jumper clip in place with the penetrating fluid of a week or so, remove it to text whether the mechanism has freed it self, if not repeat until it does or until you give up and just leave the jumper there (Or replace the switch )

Thanks for the link. I'll give it a once over tomorrow morning and trace the wiring. I'll also check to see on Vida how to get into the switch and check the schematic for info. Do the homework and make life easier!

[monkeh]

Yes, grille aids removal, or the easiest way is just remove the drivers side headlight. The connector can be found on the drivers side latch. It's a simple microswitch, nothing intelligent. It may actually have something jammed in it, but short term/permanent fix is just to bridge it.

[ShadeTek]

...on my model the latch is on the passenger side. I'll check it out tomorrow.

[Tatsfield]

There are two latches. They are through the elongated oval apertures at each end of the slam panel. See 1st photo. The two wire connector is behind the left hand aperture where the switch is located. See 2nd photo The right hand latch has the release lever.

The lead plug is removed from the connector socket and the jumper is inserted into the lead to complete the circuit as if the switch had closed.

Since your switch seems to close itself if left to settle, the sticking is minimal and plenty of penetrating fluid squirted through the left hand oval hole so that it gets everywhere including into the switch should free it. Once it is up and working, you can reconnect the lead and spay some spray oil lubricant to keep everything working.

You should try this before dismantling anything. My switch has given no trouble now for two years or more. If the penetrating oil doesn't work or the switch keeps failing, then you can dismantle but I'd avoid the bother if you can.

[ShadeTek]

I take it the switch is buried inside the mechanism? Can it be opened up or drilled in to and some Deoxit fired into the moulding?