Check Engine Light…

[DylBAT4]

I have a check engine light throwing a “communication to CAC pump auxiliary pump. Comes 1 time every 2-3 weeks. Doesn’t allow me to remote start or anything.
I’ve replaced the “CAC pump” still getting this code. It’s a
U062F
code states communication.

2022 GMC 3500HD AT4
6.6 Duramax L5P
115k miles

 

AT4 Forum Fav 👍

Precision Upfit Micro3 ATM ADD-A-Circuit Fuse Tap Link - Grab one through Amazon!

[DylBAT4]

Let me also add, it only is on for 2-3 days, I haven’t ever seen it come on middle of driving only when I start it up.

 

[DylBAT4]

Here is a picture of my coolant levels.

 

[gemarsh]

Welcome.

What does the connector look like? Code comes up as ECM lost communication with pump. If connector looks good, I would start chasing the wiring harness.

The babymax has been know for wire chafing on that circuit, so it's possible the bigmax might start having issues with that many miles.

 

[pinebaron]

Welcome

 

[DylBAT4]

Welcome.

What does the connector look like? Code comes up as ECM lost communication with pump. If connector looks good, I would start chasing the wiring harness.

The babymax has been know for wire chafing on that circuit, so it's possible the bigmax might start having issues with that many miles.

I’ve looked at the harness and it looks fine the connector does too. But maybe it’s on the inside of the plastic tubing of it. It’s a pain because the pump goes down to the driver side door.

 

[DylBAT4]

Welcome.

What does the connector look like? Code comes up as ECM lost communication with pump. If connector looks good, I would start chasing the wiring harness.

The babymax has been know for wire chafing on that circuit, so it's possible the bigmax might start having issues with that many miles.

Now that I think of it, it might have something to do with the rain too.