Code No. P0691: Cooling fan LO relay circuit (low input)
Code No. P0692: Cooling fan LO relay circuit (high input)


MAIN BATTERY COOLING SYSTEM CIRCUIT









OPERATION



DIAGNOSIS CODE SET CONDITIONS



  • When the cooling fan relay (LO) coil drive circuit monitor is set to ON while the cooling fan relay (LO) stop command is underway, the diagnosis code No. P0691 will be set.
  • When the cooling fan relay (LO) coil drive circuit monitor is set to OFF, while the cooling fan relay (LO) drive command is underway, the diagnosis code No. P0692 will be set.

PROBABLE CAUSES



  • Damaged wiring harness or connector(s)
  • Malfunction of the cooling fan relay (LO)
  • Malfunction of the EV-ECU

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III actuator test
Conduct the actuator test, and check the cooling fan relay (LO). (Refer to .)
Actuator test
  • Item No. 4 : Radiator fan 1 drive
OK: The cooling fan relay (LO) operates normally.

Q. Is the check result normal?
Go to Step 2.
Check the cooling fan relay (LO). (Refer to GROUP 14 - On-vehicle Service - Cooling Fan Relay Check .)

STEP 2. Voltage measurement at A-29X cooling fan relay (LO) (relay box) connecter
(1)Disconnect the cooling fan relay (LO), and measure the voltage at the wiring harness side.
(2)Turn the electric motor switch to the "ON" position.
(3)Measure the voltage between the A-29X cooling fan relay (LO) (relay box) connector terminal No. 3 and the body earth.
OK: Battery voltage

Q. Is the check result normal?
Go to Step 5.
Go to Step 3.

STEP 3. Connector check: A-29X cooling fan relay (LO) (relay box) connecter

Q. Is the check result normal?
Go to Step 4.
Correct or replace the relay box.

STEP 4. Check the wiring harness between A-27X EV control relay (relay box) connector terminal No. 1 and A-29X cooling fan relay (LO) (relay box) connector terminal No. 3.
Check the power supply line for open circuit and short to earth.

Q. Is the check result normal?
Go to Step 5.
Repair the wiring harness.

STEP 5. Connector check: C-108 EV-ECU connector, B-01 intermediate connnector

Q. Is the check result normal?
Go to Step 6.
Repair the damaged connector.

STEP 6. Check the wiring harness between A-29X cooling fan relay (LO) (relay box) connector terminal No. 2 and C-108 EV-ECU connector terminal No. 46.
Check the power supply line for open circuit and short to earth.

Q. Is the check result normal?
Go to Step 7.
Repair the wiring harness.

STEP 7. Diagnosis code recheck
Check again if the diagnosis code is set to the EV-ECU.
(1)Erase the stored diagnosis code.
(2)Set the electric motor switch from the "LOCK" (OFF) position to the "ON" position.
(3)Check if the diagnosis code is set.

Q. Is the diagnosis code set?
Replace the EV-ECU. (Refer to .) Then go to Step 8.
Intermittent malfunction (Refer to GROUP 00 - How to Use Troubleshooting/Inspection Service Points - How to Cope with Intermittent Malfunction .)

STEP 8. Diagnosis code recheck
Check again if the diagnosis code is set to the EV-ECU.
(1)Erase the stored diagnosis code.
(2)Set the electric motor switch from the "LOCK" (OFF) position to the "ON" position.
(3)Check if the diagnosis code is set.

Q. Is the diagnosis code set?
Return to Step 1.
The diagnosis is complete.