OPERATION
- The control (duty) signal is inputted to the fan controller (terminal No. 2) from the engine-A/T-ECU (terminal No. 18).
FUNCTION
- The engine-A/T-ECU inputs a duty signal suitable for the engine coolant temperature, vehicle speed and A/C switch position to the fan controller. In response to the signal, the fan controller controls the rotating speeds of the radiator fan and A/C condenser fan (The fan speed becomes higher as the average voltage of the terminal comes nearer to 5 V).
PROBABLE CAUSE
- Failed fan controller
- Open/short circuit in fan controller circuit or loose connector contact
- Failed engine-A/T-ECU
)
)
Q: Is the check result normal?
YES:
Go to Step 2 
.NO: Repair.
- Disconnect connector, and measure at harness side.
- Ignition switch: ON
- Short-circuit terminal No. 18 to earth.
OK: Fan motor stops rotating.
Q: Is the check result normal?
YES:
Go to Step 3 .NO: Go to Step 4
.
- Disconnect connector, and measure at harness side.
- Ignition switch: ON
- Voltage between terminal No. 18 and earth.
OK: 4.7 -
5.1 V
Q: Is the check result normal?
YES:
Replace fan controller.NO: Go to Step 5
.)
Q: Is the check result normal?
YES:
Go to Step 6 .NO: Repair.
NOTE: Before checking harness, check intermediate connector A-14, and repair if necessary.
- Check output line for open circuit.
Q: Is the check result normal?
YES:
Replace fan controller.NO: Repair.