Immobilizer bypass reversal help

[ClassicRetro]

Hi

The Cerbera AJP8 I have bought recently has had the immobilizer bypassed as the immobilizer was faulty.

I have recently fitted a new alarm and immobilizer from ABACUS.

I now need to undo the bypass. It is not clear what has been done but we know that a switch was fitted under the steering wheel which activates the started motor.

Currently the black button on the steering wheel used to start the car, when pressed gives ignition and when pressed again does not start the car. From my understanding; 1 press should activate ignition and second press starts the car.

As the second press does nothing it means that the starter is not getting power. As the car has had this immobilizer bypass treatment the new immobilizer is not immobilizing the car.

I have looked at an online wiring diagram but have not found it helpful. I can not see how the starter is supposed to be wired up from factory and from where it draws power from exactly.

Does anyone on the forum have experience in this area or has performed a bypass on there car? I don't want to have to take the dashboard out to see what they have done.

Also, does the starter moto have a relay and if so where is it please?

Thanks
Paul

[ridds]

Are you pressing and holding for the second press?

[notaping]

If you look at the Rear Harness wiring diagram you'll find the ignition box provides a starter connection which should activate on the long second press.

This would go to the immobilizer which if NOT immobilized provides an output to the starter.

This output goes to a relay in the passenger foot well, which connects a high current 12v from the 100amp fuse at the passenger 'A' pillar to the starter solenoid.

Most of this is from memory - so don't quote me

[ClassicRetro]

Thanks for the replies.

Yes I am pressing and holding on the second press but it does not activate the starter.

Where could I find the rear harness wiring diagram please?

I have removed the carpet in the passenger footwell and can not find any relays there. There is only a silver box there which I presume is the ECU? Could you be more specific as to the location of the relays in this area? I can only see relays in the boot.

Mine is a 1997 AJP8 model

Thanks

[notaping]

http://www.tvr-cerbera.co.uk/

I think it's in Rear part 1. The relay and other boxes are usually Velcro-ed to the roof of the foot well above the MBE (the big silver box)

[Markb139]

Do you hear any relays clicking in the ignition ecu (located in the boot) - you might need a helper to press buttons.
I ve recently repaired an ignition ecu that had the same symptoms. It turned out to be a broken relay and driver transistor in the ignition ecu.

Also, I believe you’d hear the fuel pump prime (assuming that’s working) when the ignition switches on and the immobiliser is not immobilising (is that a word)

Edited by Markb139 on Thursday 23 October 23:37

[Byker28i]

notaping said:

http://www.tvr-cerbera.co.uk/

I think it's in Rear part 1. The relay and other boxes are usually Velcro-ed to the roof of the foot well above the MBE (the big silver box)

Or http://www.nineelmsphotography.com/cerbera/ if its not on there