Inspection Procedure 20: Condenser Fan Relay System

OPERATION

The A/C condenser fan relay is controlled by turning on and off the power transistor in the engine-ECU.
In response to the A/C switch signal, A/C load signal, vehicle speed and engine coolant temperature, the engine-ECU controls the condenser fan relay.

PROBABLE CAUSES

Failed condenser fan relay
Failed condenser fan motor
Damaged harness (Open or short circuit between engine-ECU and condenser fan relay, Open circuit between condenser fan motor and earth, condenser fan relay and J/B, condenser fan relay and relay box, and open circuit between condenser fan relay and condenser fan motor)
Damaged connector (condenser fan relay connector, condenser fan motor connector, Engine-ECU connector)
Failed engine-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III data list

Refer to Data List Reference Table .

Item 26: A/C load signal <Automatic A/C>

Q. Is the check result normal?

	Go to Step 2 .

	Check A/C system (Refer to GROUP 55B - Troubleshooting - Trouble Symptom Chart ).

STEP 2. Check at C-105 engine-ECU connector.

Disconnect connector, and measure at harness side.
Ignition switch: ON
Short-circuit terminal No. 39 to earth.

OK: Condenser fan motor rotates.

Q. Is the check result normal?

Go to Step 3 .

Check condenser fan system (Refer to GROUP 55A - Troubleshooting - Trouble Symptom Chart

STEP 3. Connector check: C-105 engine-ECU connector.

Q. Is the check result normal?

Replace the engine-ECU. When the engine-ECU is replaced, write the chassis number (Refer to GROUP 00 - How to Perform Chassis Number Writing

). After replacing the engine-ECU, register the injector identification code and learn fuel injection (Refer to GROUP 00 - Precautions Before Service - What The Common Rail Engine Learns

Repair or replace.