No brake lights when abs light on

Abs light has been on and off intermittently recently and I believed it was due to a faulty sensor although it hasn’t been officially diagnosed. Brake pads and rotors are nearing the end of their cycle but a new problem just showed up. The brake lights no longer work when the abs and traction light come on the dash. When the abs light is off they work fine. Any ideas?

 

That’s an odd one.
The brake light power is feed through the Stop Lamp Control Relay on the VSC equipped trucks.
It’s almost like the feed leg in the relay for power isn’t making contact when the VSC light is on.

Are you sure you don’t have any ABS codes?
Not all scanners can pull ABS codes.

 

Can you still shift it out of park when the brake lights don't work?
What code(s) are present in the ABS module?

 

It does occasionally lock me in park but I’m not sure if it’s related to the brake lights, the shift lock has happened a hand full of times in the past month after a cross country move. I hadn’t thought of that correlation yet. I haven’t had the codes on the abs checked yet, just had two separate shops tell me the pads will need replaced soon.

 

My suspect would be the brake light switch, it controls the brake lights directly, sends a signal to the shift interlock, and also inputs a brake signal to the PCM and ABS.