2019 Silverado 1500 LTZ - Intermittent check engine light - wiring issue

ACV · April 2, 2024

I have a 19 with 89k on it. Since December I've had an intermittent check engine light come on. At times it will cause truck to shutter and go into reduce power mode. Multiple codes show up with the main one being P0641 (sensor reference voltage A circuit/open) along with P0016 (crankshaft position), P0106 (Manifold Pressure), P018c (Fuel pressure sensor). My assumption is there is a wiring issue causing multiple codes to go off. Seems to happen when it is raining or high humidity. I have an extended warranty until 90k and have had it into the GM dealership 3 times. The first time they repaired 5 wires on the main engine harness. The problem persisted and will continue to give a check engine code however will shut off and turn on randomly. GM says they can't do much unless the check engine light is on? There seems to be multiple bulletins on main engine harness issues. Any thoughts on source of issue is much appreciated. Love the truck but can't trust it at this point.

Johnny Gat · April 5, 2024

Me too same on my 2020 1500 LT

Stevejfy · April 29, 2024

In the last six months, twice, with the most recent being last week the light has come on but then goes off the next day. NO issues with how the truck drives. I have had Onstar do a diagnostic check and they have found nothing. It is a 2019 5.3, LT, 4x4. 8-speed. There is 55000 miles on it and if something is wrong I want to find out before 60K miles for the drive train warranty. The dealer wants >$100.00 to do a diagnostic check and I'd rather not do that if possible. Any thoughts?

GMCustomerService · April 30, 2024

On 4/29/2024 at 1:41 PM, Stevejfy said:

In the last six months, twice, with the most recent being last week the light has come on but then goes off the next day. NO issues with how the truck drives. I have had Onstar do a diagnostic check and they have found nothing. It is a 2019 5.3, LT, 4x4. 8-speed. There is 55000 miles on it and if something is wrong I want to find out before 60K miles for the drive train warranty. The dealer wants >$100.00 to do a diagnostic check and I'd rather not do that if possible. Any thoughts?

We regret to hear you are facing challenges with your Silverado and would like to take the opportunity to investigate further for you. Please send us an email to [email protected]. Be sure to include your Username and Forum name in the subject line with any additional details. We look forward to your email.

Stevejfy · May 1, 2024

7 hours ago, GMCustomerService said:

We regret to hear you are facing challenges with your Silverado and would like to take the opportunity to investigate further for you. Please send us an email to [email protected]. Be sure to include your Username and Forum name in the subject line with any additional details. We look forward to your email.

I have done as you asked. Thank you for reaching out.

Steve

Bikerjon · May 1, 2024

11 minutes ago, Stevejfy said:

I have done as you asked. Thank you for reaching out.

Steve

Best of luck Steve. Let us know how it goes.

Stevejfy · May 9, 2024

I have been in touch with General Motors customer care. They have encouraged me to get a complete diagnosis from my local Chevrolet dealership and given me a case number. I have an upcoming appointment. I hope Chevrolet covers the expense as the dealership wants $205.00 for the diagnosis. It is frustrating to have to pay for checking out annoying glitches, but i don't want to be stuck on a road in the Colorado backcountry this summer.

I'll let you all know how this turns out.

Edited May 10, 2024 by Stevejfy
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Stevejfy · June 26, 2024

The check engine light came on again. I was able to have OnStar do a diagnostic and codes; P25A, U0100, U0101 and U0146 came up. The truck is now at a local Lakewood Colorado dealership. I hope it is an easy fix and that Chevrolet can help out with the cost to repair. It seems it is something in the in the brake electonics.

GMCustomerService · June 26, 2024

6 hours ago, Stevejfy said:

The check engine light came on again. I was able to have OnStar do a diagnostic and codes; P25A, U0100, U0101 and U0146 came up. The truck is now at a local Lakewood Colorado dealership. I hope it is an easy fix and that Chevrolet can help out with the cost to repair. It seems it is something in the in the brake electonics.

We sorry to see you are having concerns with your vehicle and would like to investigate this further for you. Please send us an email to [email protected]. Be sure to include your Username and Forum name in the subject line with additional details. We look forward to your email.

Texas Bob · March 17

I’m having the same issues and I’m in the middle of Colorado. There are no Chevy/GM services dealerships near me. What did the dealership service department diagnose the issue being. This has continue to be an issues that continues to exist and getting worse.

tjonesdfw · March 17

Had the same on our '21 5.3 for the first 20,000 miles. After cam and crank sensor replacements, then two attempts at a chaffed/tight wiring harness TSB, and multiple software issues, it finally seemed to resolve itself.

Texas Bob · March 17

I’m having the same issues and I’m in the middle of Colorado. There are no Chevy/GM services dealerships near me. What did the dealership service department diagnose the issue being. This has continue to be an issues that continues to exist and getting worse.