Is there any documentation on how to read the codes when in Engineering test mode?

 

It's in the FAQ??

Here is a copy.
.
.
.

 

But be aware they are NOT the current PCM (aka ECM) engine codes. And are not cleared with battery off or via a typical OBD tool so can be from any time in the car's life.

 

thanks JagV8 - that is good info. Quick question - is their documentation on the meaning of the DTC codes?

thanks

 

I posted it before if you care to look but I really would just not bother. You'd be chasing shadows. Get a current complete list of codes from all modules if you really care.

ETM is useful for diagnosing fuel senders, faulty ECT sensor, gauge reset, etc.