Swapped bumper, ACC & fogs no longer working

J Peterman

Go Kart Newbie
So I swapped a facelift R bumper onto my GSW S with my retrofitted GSW fog lights using dremeled out R-line fog covers. This obviously involved removing the front grill and bumper cover. Unfortunately, now neither the fog lights or ACC work (with lights on dash). Before the bumper swap, all coding and functions were working properly with a fog harness from AliExpress and DeAutoLED fog bulbs/resistors/drivers.

B121F15 Left fog light bulb open/short circuit to B+ (static)
C110300 ACC sensor misadjusted (static)
U111000 function restriction due to communication interruption (intermittent)

I removed the fog light housings and DeAutoLEd bulb/resistor/driver assembly for a few weeks while preparing the bumper swap. I taped over the fog light harness ends, but we had a few rainstorms during that period of time (maybe the cause of the fog light short?). I did get an ACC light just prior to installing the new bumper when I tried changed traction setting ESC Sport. Hasn’t been working normally since.

Thoughts? I’m thinking next step is a new fog harness and getting the ACC recalibrated under warranty, unless something might be pinched from reinstalling the new bumper. The fogs flicker with low output or don’t come on at all.


Drag Race Newbie
When you turn off ESC your cruise is disabled. Sounds like you have a coding issue with ESC.


New member
Auburn, AL
Thanks for the reply. No. But I’ve removed the entire bumper/grill assembly in the past without disconnecting the battery without any ACC errors?
Did the car get keyed on or wake up while the sensor was disconnected? Seems like the car tried to read the sensor while it was out of alignment or disconnected.

J Peterman

Go Kart Newbie
Nope. All buttoned up with ACC and fog harnesses connected before I turned on the ignition to check the fogs. Then noted the persistent ACC error and OBD scanned the codes listed above. Traction control setting turned back to normal and the ACC error persists. Checked ACC connection and it's good, no debris in the vicinity of the sensor or anything obvious like that.

The fogs have never worked properly since the swap (driver's side flickers with low output, passenger side initally did the same, now doesn't come on at all). I swapped the whole DeAuto light assembly for a brand new one and same deal, so I suspect the harness shorted from moisture (new one on the way).


Ready to race!
You probably need to get your radar re-aimed [C110300 ACC sensor misadjusted (static)]. The two bumpers reflect radar waves differently and the aiming would need to be adjusted, or you may have bumped the radar with the bumper during removal or install. Other car companies who use the same radar supplier require re-aiming every time a bumper is removed.