Hi Everyone,
I'm newly registered but have been reading all the threads that I can find on Immobiliser issues, so please do not shoot me down as I'm asking for some further help.

My sons Grande Punto 1.2 8V 56 plate 75K miles has suddenly stopped running, prior to this it ran perfectly with no problems at all.

Immobiliser light on permanantly, ABS light intermittant, temp guage needle travels H-C etc, etc.

To date we have checked all the recommended earth cables (replaced main one battery - chassis - gbx) changed the battery for a new unit. Replaced the ECU, body computer (glovebox fusebox unit) and ignition barrel + pick up ring (the ecu, bc & lock set were from a similar aged scrapped GP) The engine compartment fuse box has been removed sprayed with water dispersant and dried out thoroughly (it was dry to start with but we are trying to cover all bases !!)

However the immobiliser light still remains on and the starter motor does not operate. Do we need to get the immobiliser reset by FIAT? (I thought that changing the coded set would avoid this !!)

Any further hints or direction would be appreciated :bang:

Are you using the keys from the scrapped car along with the body computer and ECU, if so then it sounds like your fault was originally and still is wiring.

Hi T14086,

Yes we are using the key supplied with the ECU & BC, unfortunately there were no sets with two keys available.

I would be checking (which you should of done in the first place) supplies to the ECU, engine fusebox and body computer.

Do you have access to a code (data) reader?

Hi,

yes we have a code reader - it was unable to pick up / link to the car system.

Post the first failure of the car the RAC spent a lot of time attempting to diagnose the issue. As with our Code reader - initially they could not link with the car system, however, after some time the tech was able to gain access to the car system.

Codes as follows :- Control Body U0019, U0426, U1701,
CAN U1701, U0019, U0001, U0426
Power steering U1701, U1003
ABS U0001, C1221, C1212, U1701

This work was c/o prior to the ecu / bc were changed.

Can you tell me what voltages should be expected at the various supplies/pins to the fuse box & bc ?

Post cx of the ecu, bc etc - my OBD reader still fails to link with the car system.

As previously - any instruction/direction would be appreciated.

They are all CAN related faults, i'd be checking the CAN circuit which would also explain why you cannot communicate.

Hi T14086,

Many thanks for the reply, but can you provide some more info on the CAN circuit please, ie where the circuit runs to and from and also what voltages to expect ??

Did u manage to sort this I have the same problem ?