Diagnosis Procedure

WARNING: This page is about a different car, the 2018 Nissan Titan XD and 2018 Nissan Titan. However, it is still accessible from the selected car via links, so may be relevant.

CHECK CONNECTOR
1. Turn the ignition switch OFF.
2. Disconnect the battery cable from the negative terminal.
3. Check the terminals and connectors of the PTC heater control unit for damage, bend and loose connection (unit side and connector side).
Is the inspection result normal?

YES

GO TO STEP 2 .

NO

Repair the terminal and connector.

CHECK HARNESS FOR OPEN CIRCUIT

Disconnect the connector of PTC heater control unit

Check the resistance between the PTC heater control unit harness connector terminals.

PTC heater control unit harness connector			Resistance (Ω)
Connector No.	Terminal No.
M131	1	9	Approx. 54 - 66

Is the measurement value within the specification?

YES

GO TO STEP 3 .

Repair the PTC heater control unit branch line.

CHECK POWER SUPPLY AND GROUND CIRCUIT
Check the power supply and the ground circuit of the PTC heater control unit. Refer to Diagnosis Procedure .

Is the inspection result normal?

YES

Replace the PTC heater control unit.

YES

Error was detected in the PTC heater control unit branch line.

NO

Repair the power supply and the ground circuit.