Auxiliary Heater (ZHZ)

9023-RED LED CIRCUIT LOW (ZHZ)

For a complete wiring diagram, Refer to the Wiring Information Electrical Diagrams.

- When Monitored:
Continuously.

- Set Condition:
The Warm Water Auxiliary Heating 2 Control Unit detects a short to ground.





1. DTC IS ACTIVE
1. Turn the ignition on.
2. With the scan tool, read DTCs.

Is this DTC active?

Yes

- Go To 2

No

- The 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. Verification Tests.

2. HEATER BOOSTER BUTTON
1. Turn the ignition off.
2. Disconnect the Heater Booster Button harness connector.
3. Turn the ignition on.
4. With the scan tool, read DTCs.

Is this DTC active?

Yes

- Go To 3

No

- Replace the Heater Booster Button.
- Perform the BODY VERIFICATION TEST. Verification Tests.

3. CHECK FOR CIRCUIT SHORTED TO GROUND
1. Turn the ignition off.
2. Disconnect the Warm Water Auxiliary Heating 2 Control Unit harness connector.
3. Measure the resistance between ground and the related circuits.

Does the Ohm meter read open circuit?

Yes

- Replace the Warm Water Auxiliary Heating 2 Control Unit.
- Perform the BODY VERIFICATION TEST. Verification Tests.

No

- Repair the circuit shorted to ground.
- Perform the BODY VERIFICATION TEST. Verification Tests.