po601 code

[William Woody]

Got an 08 GMC Yukon throwing a po601 code, it lost power while driving, was wondering if there is any common problem with GM I need to look at before replacing the PCM?

 

[asilverblazer]

Address the 'lost power while driving'. Start checking the battery, battery cables, connections and grounds. Check the connections to the PCM for corrosion, bent pins, damaged wiring.

 

A messed up PCM is very rare. 

[Jsdirt]

Common problem is WIRING. Loss of power or ground to the PCM can cause this code along with the symptom you described.

 

Wiring today is low-bidder garbage (along with just about every other part) - doesn't take very much at all to rub through and short to ground or power, or become an open. Sometimes this garbage wire will break INSIDE the jacketing (insulation), making detection impossible without the "tug test". If you grab the wire and keep a suspected break in between your hands as you attempt to pull the wire apart, and it stretches like Silly Putty, you've found that particular issue. This can happen in a billion varying degrees - so if one strand of copper is all that is making the connection, the component requiring power will intermittently fail when current draw is highest.

 

That particular kind of wiring failure used to never exist. Welcome to the 21st century ...

 

That said, check the basics first, starting with battery cables as mentioned.

Edited April 7, 2023 by Jsdirt