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-   -   Alarm issues, non starting (

Coachwhip Jan 14th, 2020 15:16

Alarm issues, non starting
This is for a 1998 v70. Siren behind drivers wing. Throttle cable engine.

Car was unlocked with key (no remote), boot opened and alarm triggered. Couldn't get alarm to switch off so disconnected battery.
Now as soon as I connect battery again the alarm will go off. This never used to happen before if I disconnected battery. Drivers lock does not switch off alarm.
I looked in vol-fcr. Codes were alarm siren faulty and left ultrasonic. Cleared codes, still alarm is running. Disconnected alarm siren under the wing, no siren but hazards running and not starting. Even with siren disconnected the siren faulty message comes up.

I've had the door lock out... microswitch clicks... Any way to test it on bench?
Should alarm arm the moment you connect battery? Even though bonnet is open, even if doors are left open?

I'm actually not bothered about having alarm working if need be, just need hazards off and immobilizer off.

Is there anyone that is good with these alarm circuits? I don't mind replacing a part if I can find why it's triggering straight away.



Cookeh Jan 14th, 2020 16:19

It will trigger until immobilizer is deactivated. At least that's the problem I had, ended up having to buy a new fob and alarm relay as mine was dead (causing issue in the first place).

Pull the relay for the alarm system, in the big relay board under the drivers side front panel trim (beneath the steering wheel). Long term, you can plug it back in and program a new fob to it or buy new relay and fob.

Failing that, you can just pull fuses in accordance with this thread: Clicky

Coachwhip Jan 14th, 2020 16:49

The alarm is a denso one I believe, which is different to the 850 alarm.. and also different to the 99 onwards v70.
Trust me to get an awkward one.

Cookeh Jan 14th, 2020 21:12

Perhaps something in here might be of use? I admit to giving it little more than a skim read.


Gaztech Jan 14th, 2020 22:04

Have you tried locking and unlocking the boot via the boot door lock or simply locking and unlocking the car with the key in the drivers door?

Coachwhip Jan 14th, 2020 22:16

I'll check out the transmitter. Above left knee, uk or us? Glove box is out anyway. So I'll give it a good look if it's not raining.

Yes tried the locks. Ordered a used lock to swap over, hoping that might do it.

Could be that even with battery off, the ecu remembers that the alarm was tripped and goes straight off. If so, then door lock switch not working would account for it. But I'd rather check it first than just replace.

Gaztech Jan 14th, 2020 22:23

The module is above right drivers knee UK. Takes 2 minutes to change. You slide it to the right off the bracket to remove then unplug

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