For a complete wiring diagram Refer to Section 8W.When Monitored:With the ignition on.Set Condition:The Totally Integrated Power Module (TIPM) detects an HIGH condition.Possible Causes(L673) LEFT TRAILER TOW LAMP CONTROL CIRCUIT OPEN(L673) LEFT TRAILER TOW LAMP CONTROL CIRCUIT SHORTED TO VOLTAGETOTALLY INTEGRATED POWER MODULE1. TEST FOR INTERMITTENT CONDITIONTurn the ignition on.With the scan tool, clear all DTC'sTurn on the Left Turn Signal.With the scan tool, read DTC's.Does the scan tool display active: B166C-LEFT TRAILER TOW LAMP CONTROL CIRCUIT HIGH?YesGo To 2NoThe condition that caused this symptom is currently not present. Check for an intermittent condition by inspecting the related wiring harness for chafed, pierced, pinched, and partially broken wires. Also, inspect the related connectors for broken, bent, pushed out, spread, corroded, or contaminated terminals. Repair as necessary.Perform the BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE) 2. (L673) LEFT TRAILER TOW LAMP CONTROL CIRCUIT OPENTurn the ignition off.Disconnect the TIPM C6 harness connector.Disconnect the Left Trailer Tow Lamp harness connectors.Measure the resistance of the (L673) Left Trailer Tow Lamp Control circuit between the Left Trailer Tow Lamp harness connectors and the TIPM C6 harness connector.Does the ohm meter read open circuit?YesRepair the (L673) Left Trailer Tow Lamp Control circuit for an open.Perform the BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE) NoGo To 33. (L673) LEFT TRAILER TOW LAMP CONTROL CIRCUIT SHORTED TO VOLTAGETurn the ignition on.Measure the voltage on the (L673) Left Trailer Tow Lamp Control circuit.Is there any voltage present?YesRepair the (L673) Left Trailer Tow Lamp Control circuit for a short to voltage.Perform the BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE) NoReplace the Totally Integrated Power Module (TIPM) in accordance with the Service Information.Perform the BODY VERIFICATION TEST - VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE)