Operation CHARM: Car repair manuals for everyone.

HVAC






902A-BLOWER STAGE 1 RELAY CIRCUIT OPEN (ZHZ)

For a complete wiring diagram refer to Diagrams/Electrical.

- When Monitored:

Continuously.

- Set Condition:

The Warm Water Auxiliary Heating 2 Control Unit detects an open circuit.






Diagnostic Test

1. DTC IS ACTIVE

Turn the ignition on.

With the scan tool, read DTC's.

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 BODY VERIFICATION TEST - VER 1. Body Verification Test


2. CHECK FOR OPEN CIRCUIT

Turn the ignition off.

Disconnect the Warm Water Auxiliary Heating 2 Control Unit harness connector.

Disconnect the Blower Stage 1 harness connector.

Measure the resistance of the related circuits between the Warm Water Auxiliary Heating 2 Control Unit harness connector and the Blower Stage 1 harness connector.

Does the ohm meter read open circuit?

Yes

- Repair the open circuit.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Go To 3


3. BLOWER STAGE 1

Turn the ignition off.

Connect the Blower Stage 1 harness connector.

Measure the resistance of the related circuits at the Warm Water Auxiliary Heating 2 Control Unit harness connector.

Does the ohm meter read open circuit?

Yes

- Replace the Blower Stage 1.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test

No

- Replace the Warm Water Auxiliary Heating 2 Control Unit.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test