U0166-LOST COMMUNICATION WITH AUXILLARY HEATER CONTROL MODULE

For a complete wiring diagram, refer to the Wiring Information.

When Monitored:
Continuously while the system is active.

Battery voltage between 10.0 and 16.0 Volts.
Set Condition:
The Powertrain Control Module (PCM) recieves a CAN BUS message from the Totally Integrated Power Module (TIPM) that communication was lost with the Cabin Heaters.

Possible Causes
CAN BUS CIRCUITS OPEN OR SHORTED
DTCS RELATED TO BATTERY VOLTAGE, IGNITION, OR VIN MESSAGES
CABIN HEATERS POWER AND GROUND
TIPM NOT CONFIGURED CORRECTLY
CABIN HEATERS
POWERTRAIN CONTROL MODULE (PCM)

1. ACTIVE DTC

NOTE: Diagnose all CAN B and C communication DTCs before continuing.

1.	Ignition on, engine not running.

2.	With a scan tool, view DTCs.

Is the status Active for this DTC?

Yes

(Refer to 29 - Non-DTC Diagnostics/Communication - Diagnosis and Testing) and perform the Stored Lost Communication DTCs diagnostic procedure.

2. CHECK FOR CABIN HEATER DTCs IN THE TIPM

1.	With the scan tool, read DTCs in the TIPM.

Are there any Cabin Heater DTCs present in the TIPM?

Yes

(Refer to 28 - DTC-Based Diagnostics/MODULE, Totally Integrated Power (TIPM) - Diagnosis and Testing) and perform the diagnostic procedure for the Cabin Heater DTC present in the TIPM.

Replace and program the Powertrain Control Module (PCM) in accordance with the service information.
Perform the PCM VERIFICATION TEST. (Refer to 28 - DTC-Based Diagnostics/MODULE, Powertrain Control (PCM) - Standard Procedure).