Picture of the device would help. Pull it out and look for part numbers.

 

256 miles doesn't sound "new", more like "briefly used before being returned" or "demonstration vehicle".

Yeah, pic of the device and where it's plugged in.

As for the error code, get documentation from the dealer, that they entered the problem your truck is having into their system while it's under warranty. Get it put down on paper, as GM is obliged to fix it, even if they don't figure out how to until have your warranty has run out. And perhaps try contacting GM directly about the problem, as your dealer may just be blowing you off because they don't want to do the job...

 

I bought this 2020 new and today I had it in for a check engine light P04FB. Two things; the dealer says the error is because of moisture but there is no fix for it, and it is labor intensive. So, when I'm out of warranty I will have to pay for the labor when they get a fix.

So…, is it still under warranty or not? If yes, then I’d definitely be on their case to get it fixed. Saying it’s because of moisture and is labor intensive clearly tells they know what’s going on. Yet there’s no fix? What??? The fix is the prevent the moisture getting to where it can cause the error. Duh…

Something stinks here.

 

Related to this connector/moisture issue?

Communication DTCs Set on 3.0L Duramax Diesel Engine – TechLink

gm-techlink.com

Communication DTCs Set on 3.0L Duramax Diesel Engine
January 30, 2023
Several communication DTCs may be set on some 2022 Silverado 1500, Tahoe, Suburban, Sierra 1500, Yukon and Escalade models equipped with the 3.0L Duramax diesel engine (RPO LM2). Along with an illuminated Check Engine MIL, DTCs U1345 (Engine Control Module LIN Bus 1), U02A9 (Loss of Communication with Charge Air Cooler Pump), U0284 (Lost Communication with Active Grill Air Shutter Actuator 1) and U0285 (Lost Communication with Active Grill Air Shutter Actuator 2) may be set in the Engine Control Module (ECM).
Based on the specific DTCs set in the ECM, there are several possible repairs to perform.
Electrical Connector
DTCs U02A9 and U1345 may be caused by an unsealed pump electrical connector allowing water leakage into the (M10) connector. Moisture introduced into the charge air cooler pump electrical connector may lead to communication failure.
Check the CAC Pump connector sealing. (Fig. 1) Be sure to look for any corrosion at the pump due to possible water leakage.

Fig 1

Wiring Harness to In-line Connector
DTCs U1345, U0284 and U0285 may be caused by the engine wiring harness-to-active grille air shutter actuator in-line connector. The connector may not be properly connected, not properly held in place by the rear clip, or may be grounded on the radiator. Check the connection of circuit 4621 for any these possible concerns. (Fig. 2)

Fig. 2

Pinched Wiring
DTCs U1345 and U0284 may be caused by the active grill air shutter wiring being pinched at the radiator support.
Check the routing of the active grill air shutter wiring, especially at the lower-left corner of the shutter, to determine if there are any possible damaged points in the wiring. (Fig. 3) Repair the wiring as needed.

Fig. 3

For additional information, refer to Bulletin #22-NA-252.

 

I bought this 2020 new and today I had it in for a check engine light P04FB. Two things; the dealer says the error is because of moisture but there is no fix for it, and it is labor intensive. So, when I'm out of warranty I will have to pay for the labor when they get a fix. 2nd thing. There is something plugged into my data port, not the OBD 2, and no one can tell what is it, except that is is not a chevy device. The dealer i bought it from said maybe after market steps. I bought this new with 256 miles on it. Can anyone tell me what might ben there?

 





I had time to crawl in there and take a look. It is not a device. It is just an extender or adapter to the ODBD 2 connector. Not sure what the mechanic was thinking, without looking a little closer at the cable. It is unbolted from the bracket, but they may have done that when I had it for a tailgate sensor issue.

 

Where does that extender/adapter go to? Splitters and multiple obdii devices attached to the port can cause problems. I would remove it unless you need it connected for some reason, and disconnect it when diagnosing the truck.

 

Where does that extender/adapter go to? Splitters and multiple obdii devices attached to the port can cause problems. I would remove it unless you need it connected for some reason, and disconnect it when diagnosing the truck.

Yeah, that is what chevy is saying, that it it could be throwing false codes.

 





























Pulled thuis out today. I'll look these up later.

 

Yeah, from googling the model number, it probably is some kind of tracker device for a fleet (probably not for a loan company, as it would probably be more hidden). Remove it and then get it rechecked.

Edit: and again, that would be a sign the vehicle isn't new. And that the dealer is a moron or just not interested in fixing your truck, for not unplugging it and then reading codes

 

MyCar VS-4LU-1 Smartphone Controller | 4G/LTE North American Coverage

This is the MyCar VS-4LU-1 4G/LTE Smartphone Controller Manuals & Guides Install Guide Subscription Fees Monthly/Yearly Fees FREE first year service (includes GPS tracking) 1-year service plan renewal cost: $39.95 USD (includes GPS Tracking)3-year service plan renewal cost: $99.95 USD (includes...

lockdownsecuritycanada.ca