Lets focus on the Driving light/parking brake light/beeper problem first.
I think you have a Light control module as shown in the photo. Mine is in the electrical compartment Driver Side.
Looking at the photo, you can see the red/white wire. I have modified the circuit so that I can flash my driving lights while on the road.
The way this circuit works, is that the parking brake switch grounds the red/white wire. When the wire is grounded, the headlights are off (driving lights). This wire also connects to the LBCU. The LBCU looks at this wire, AND if you are in "Drive", it sounds the beeper because it thinks you want to move with the bake set.
The first thing to do is block your wheels, start the engine, and release the parking brake. Then measure the voltage on the red/white wire.
It should be 12v....but I bet it is 0v (grounded).
This will indicate the problem....then you have to trace the source.
2014 40QBH Phaeton DP Cummins 380HP ISL, Freightliner XC, 2019 Jeep Grand Cherokee Trailhawk TOAD
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