Good day all! I'm hoping someone else here has been through my battery replacement nightmare and can help me, as well as others. I recently had a starting issue and determined that the battery in my 2019 Equinox needed to be replaced. I went to the dealer and picked up a ne AC Delco OEM battery. I installed it myself. Out on the first road trip and making a right hand turn I noticed that the right turn indicator was blinking fast and determined that my right rear bulb wasn't working. I pulled the tail light to replace the bulb but the bulb looked good. I put the new bulb in anyways but still not working. I found no current to the bulb connector. I then noticed that the front left HID headlight wasn't working either. I swapped the bulb to the right and found that the headlight bulb was good. Once again, found no power to the connector. I pulled every connector from the BCM and made sure terminals were clean and have had no luck. It seems like it may be a poor ground but I can't be sure. Has anyone had this issue? Can someone point me in the right direction? Thanks!

 

GM recently updated a TSB that adds more connectors to check and include newer models up to the 2023 model year. This may be related to the issue you're having.

I've linked the older version here because I can't find the newer one anywhere online yet (it was released Sept 7, 2022). If you have access to GM Service Information or AllData, the latest version of this bulletin is #22-NA-170 or SI doc 6144671. A dealership might be willing to print it for you if you kindly ask.

In a nutshell, it says to check for water intrusion at:

all the bulb connectors going to the right rear (outer) tail lamp assembly.

If DTC P12A6 is found, check the body to fuel tank connector (X350).

K9 BCM connector

If you're seeing a "Service Safety Restraints" message and/or DTC B0073 is found, inspect connector X320 at the right front seat harness to body harness.