Good morning
My issue is, I have power to my headlights, turn signals and front amber lights. I have rear taillights and blinkers, but no power to the rear red marker light. I took my multimeter to check for power and nothing. Checked breakers seems to be okay. What is my problem. Thanks, TowBarman
year and model? pushbutton or 3 lever lightswitch?
So taillights, brake and turn but no rear markers? Hmmm do the reverse light work? All the rear lighting grounds thru TL 97 which is located I think on the drivers side frame to the rear of the axle under a 10Mm bolt. if the other rear lights are OK, the ground probably is as well.
taillight and marker power both originate at k20, with the taillights passing thru CB80 and ALL the markers passing thru CB67. so if the front markers are OK then CB67 must be OK.
Marker light power from CB67 feeds TB1 pin 1-26, with only 10 different circuits connected to that group. Where the rear markers become distinctly separate is at TB1 pin 11. perhaps you have an issue there and the wire has been pulled out/disconnected at TB1-11. from 1-11 it goes to j51-7 also in the passenger dash near the power panel. from there it is straight back to a mass junction point E21 buried in the wiring harness just forward of the pintle hitch where it splits to feed the 7 rear marker lights... Now of course this is specific info for a A0, but these trucks are very similar IRT basic light wiring...
