ABS light on TCM light on in IPK

FRASER CHURCH

MEMBER
2008 LAND ROVER DISCOVERY 3
2.7L
V6
AUTOMATIC
75,000 MILES

Got an issue with a disco 3 when idling or driving faults come up on Instrument cluster ignition on and off it clears happens again a few minutes later. DTC read are U0100-87 PBM lost comms with engine control module control module A. It has had a new instrument cluster and power train control module. Disconnecting the PCM connectors and the battery I put one multimeter led to a good ground and test all the wires at the PCM I find them all clear except one wire that has continuity with the multimeter bleep. I think I have a short to ground in the engine bay harness, have you seen this issue before?

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
47,643 POSTS

Yes, this is a problem that any car can have but I would check the engine control module relay to make sure it is working and giving power to the PCM. Here is a guide to help test it and the location of the relay (under-hood fuse panel) I have also included the engine wiring diagrams below and a guide to help test the wiring as well.

https://www.2carpros.com/articles/how-to-check-an-electrical-relay-and-wiring-control-circuit

and

https://www.2carpros.com/articles/how-to-check-wiring

Check out the diagrams (below). Let us know what happens and please upload pictures or videos of the problem.

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