Problem: The technician stated that this
truck has melted four TIPMs in the last four months and the
customer just brought it back complaining that the parking lamps
do not operate correctly with his trailer connected.
Details: The technician inspected the TIPM
to find it melted (see image). When the technician called
Tech-Assist, he stated that no DTCs were set in any module and
all power/ground cables and connections from the batteries were
good. The T-A consultant suggested looking for any aftermarket or
poorly-spliced accessories. Something on the lighting system had
to be overloading the TIPM circuits.
Confirmed Repair: The technician inspected
the lighting harnesses and found an aftermarket trailer harness
spliced directly into the lighting circuits at the taillamp.
After routing the add-on trailer wiring to a dedicated circuit,
he replaced the TIPM again. After a long test drive, the lighting
system seemed to work normally and the TIPM wasn’t melted. The
customer called back four months later with no problems to
report. It took a while to really confirm the fix but it was well
worth the wait.
NOTE: On this model, it’s advised to use a
dedicated trailer circuit.