Do I need to do a VAT Relink ???

[Ninety8C5]

I had a spare PCM fixed (previously fried) for my car. I can read the PCM (with bench harness) and it has the correct OS, tune and VIN for my car. When I tried to use it yesterday, it would not play nice with the other controllers. I got reduced engine power, service traction control and ABS messages. I could not connect to the PCM wth the Tune Tool with the PCM in the car.

If I enable a VAT relink will that let this PCM talk to the other controllers or is there something else I need to do? :confused:

TIA

[Ninety8C5]

Does anybody have any idea howto solve this problem ? :crash:

[joecar]

On a 98 C5...?

I can't find any diagrams for this...

To be able to do a VAT relink, the PCM must already be able to communicate with the BCM.

[Ninety8C5]

Yes, a 98 C5.

My thought, which is probably flawed, was to enable the VAT relink with a bench harness. Then unplug the power and put the PCM back into the car.

Hopefully when the power was restored the PCM would talk to the BCM.

Might work, no chance in hell or any other suggestion to get the PCM to play nice with the other modules? :confused:

[Ninety8C5]

My thought, which is probably flawed, was to enable the VAT relink with a bench harness. Then unplug the power and put the PCM back into the car.

I just re-read page 85 Security/VAT relink in the Tune document and it sounds just like my plan. :doh2:

As soon as I feel better, I guess I will try it.

[joecar]

When you click on the [VAT relink] button, EFILive instructs the PCM to set a flag that will cause it to re-link to any BCM (that it can “see”) when the ignition is next switched on.Let us know... :cheers: