V50 Electrics : V50 - Immobiliser - Non Start C326

[Welshi]

Hello

Im a bit stuck with a fault, I have a Volvo V50 2009 R-Design 2.0D, It has not been used much due to lockdown, and I went to it last week, turned over once and since then nothing, ive replaced the battery, It takes the key and unlocks the steering wheel but comes up with immobilizer please try start again, I have checked all the fuses, relays and power supplies to the ecu and cem, tried both keys, checked all the plugs in the foot-well and checked the cem for corrosion but still no luck, the fault code im getting on Vida and Delphi is C326 - Communication fault with control unit - Permanent-faulty signal.

Ive been though the forums with not much luck, the only advise I see is a software update at Volvo, sadly due to my location this is not possible.

Any help would be appreciated

Rob

[PCW8256]

It sounds like your CEM and ECU have lost some form of communication. Sadly it sounds like it would need reprogramming. I am at a loss as to why this happened.

Google revealed something here:

http://www.codecard.eu/small-soft/vo.../prod_989.html

Have you tried disconnecting the battery and joining the positive and negative terminals on the car?

Perhaps leave the car without voltage for a day or two.

[PCW8256]

I also found this

https://www.youtube.com/watch?v=FHyE8Vm1QIA

[BmouthVolvoGuy]

Hi Rob,

I have got a very similar problem on my 2010 V50 2.0D

I've been on a (costly) diagnostic journey with no joy.

I've had the ECU checked by ACTronics.co.uk and all good.

I am thinking reprogramming the CEM might be the next move, but have no idea what kind of a job that is (i.e. would all associated parts also need to be reprogrammed?)

Anyway, did you have any joy?

Thanks,

Sam.

[ele288]

It's involving reading ecu and cem and adding key code to cem or just reload cem with vida online

[Clan]

Originally Posted by BmouthVolvoGuy

Hi Rob,

I have got a very similar problem on my 2010 V50 2.0D

I've been on a (costly) diagnostic journey with no joy.

I've had the ECU checked by ACTronics.co.uk and all good.

I am thinking reprogramming the CEM might be the next move, but have no idea what kind of a job that is (i.e. would all associated parts also need to be reprogrammed?)

Anyway, did you have any joy?

Thanks,

Sam.

There have been some cases only on the 2.0D ECU of loosing its data if the car has had a flat battery for a few days or more ...hence loosing the immobiliser codes ... All you can do it get it towed to a dealer for a ECU Software reload as a first action ...