pomerlo

Next I would try disconnecting the battery for about 15 minutes to perform a reboot of your BCM. Meanwhile the battery disconnected, I would go to the BCM and reconnect all connectors making sure that none are loose.

CRF_263

Did you ever figure this problem out?
I have the same issues with a 2003 Chevy Express 2500. While driving with the lights off, they will turn on and off while hitting bumps. If you hit the top or bottom of the steering wheel they will turn back off. It’s just the running lights that come on. I’ve had all the dash and column apart looking for the issue, switched out all the switches I could with another van the same year and all.

My interior lights seem to not work with the door while this is going on too.
It did stop for awhile and work fine. Now it’s acting up again.

Revken

Sorry, I try hard not to abandon a thread unresolved.

My struggle to diagnose this was that it was a compound issue.

1. The headlamp switch was worn out working intermittently. $10 at a junk yard fixed that part of the problem.

2. The DRL module had gone bad a second time. Their solder points get hair fractures in them and temperature makes the difference between solid and intermittent connection. The module controls multiple functions, like blinkers and Day Time Running lights, which also disrupted my headlight function.

The DRL module was only $40 and it was clipped under the steering wheel, behind the dash, to the passenger side of the cavity. It was hard to find the first time as it was up against the backside of the dash on my year while some described it in a different location.

I recommended swapping the DRL module first when headlight light issues arise.

Hope that help. Good luck getting her fixed!