Still trying to figure out why my 05 Super V8 sometimes pops into neutral when kicked down at highway speeds. I've been using my iCarsoft reader to get the codes and clear them so I can see the errors each time. The common thread seems to be communication between the ECM and the other modules in the car. I get U2523 "CAN message timeout" from at least 4 different modules and P1797 "CAN Transmission Control Module to ECM malfunction" This all seems to point to a connection problem at the ECM.

Strangely the iCarsoft reader can't seem to talk to the ECM either. When I stop on that module I get a message on the reader that says " Fault in communication with vehicle ECU" and I can't see the status of the ECM or any error codes.

Battery is new
Headlight grounds have been cleaned
Transmission connector is dry
Coils and plugs are fresh within a year
No ABS sensor errors are posted
All other aspects of the car work perfectly

It seems like I should check the connector on the ECM and clean it out with some contact cleaner.

Any other knowledge or suggestions on the subject?

Much Thanks
Jeff

 

Many seem to find the iCarsoft does that with the ECM unless you persuade it to use the right protocol i.e. it's a software bug in the iCarsoft.

 

So far no reader has ability to read the 04 engine module in my 04.

The 07 has no problem at all communicating with the icarsoft

 

IDS/SDD is the way to go...

 

Which other tools have you tried?

IDS/SDD will likely work.

 

I have two readers, the icarsoft930, as well as a LaunchV11+,both are good units.

My next move is to acquire a dealer level type that can reflash as well as program modules.

That way i should NEVER need to seek the dealers assistance beyond the parts dept.

 

I can also confirm that the iCarsoft, mine a LRII, does not communicate as well with my 05 as it did with my 08.

 

Does an elm327 work? They're basic but at least do the PCM (aka ECM) and are very cheap.

 

I have a ,03 s-type I found the wiring harness going to the trans was laying On the exhaust causing all types of issues and it was just enough that the connector dried out and melted and even caused a short at the fuse box ( under hood ) hope this helps