Honda HR-V: Radiator Fan High Speed Circuit Troubleshooting

1. Fuse check.

1. Check the following fuses.

Are the fuses OK?

YES

Reinstall the fuses, then go to step 2.

NO

Replace the fuse(s), and recheck. If the fuse(s) blows again, repair the short to ground on the No. B12 (30 A), the No. B31 (7.5 A), and/or the No. C24 (7.5 A) fuse circuit(s).

2. Radiator fan and fan control relays check.

1. Check the following relays.

Are the relays OK?

YES

Go to step 3.

NO

Replace the relay(s).

3. Open wire check (+B MAIN FAN line).

1. Measure the voltage between test points 1 and 2.

Is there battery voltage?

YES

Go to step 4.

NO

Repair an open in the +B MAIN FAN wire between the radiator fan relay and the No. B12 (30 A) fuse.

4. Determine possible failure area (GND line, others).

1. Remove the fan control relay.
2. Connect terminals A and B with a jumper wire.

3. Connect terminals A and B with a jumper wire.

Does the radiator fan run at high speed?

YES

Remove the jumper wires, then go to step 9.

NO

Remove the jumper wires, then go to step 5.

5. Radiator fan motor operation check.

1. Test the radiator fan motor.

Is the motor OK?

YES

Go to step 6.

NO

Replace the radiator fan motor.

6. Open wire check (GND line).

1. Check for continuity between test points 1 and 2.

Is there continuity?

YES

Go to step 7.

NO

Repair an open in the GND wire between the fan control relay and ground (G301).

7. Open wire check (MAIN FAN MOTOR line).

1. Disconnect the flowing connector.

Radiator fan motor 2P connector

2. Check for continuity between test points 1 and 2.

Is there continuity?

YES

Go to step 8.

NO

Repair an open in the MAIN FAN MOTOR wire between the radiator fan relay and the radiator fan motor.

8. Open wire check (FAN HI/LO RLY COM line).

1. Check for continuity between test points 1 and 2.

Is there continuity?

YES

Check for poor connections or loose terminals at the under-hood fuse/relay box and the radiator fan motor.

NO

Repair an open in the FAN HI/LO RLY COM wire between the fan control relay 5P and the radiator fan motor.

9. Open wire check (IG2 A/C line).

1. Turn the vehicle to the ON mode.
2. Measure the voltage between test points 1 and 2.

Is there battery voltage?

YES

Go to step 10.

NO

Repair an open in the IG2 A/C wire between the radiator fan relay and the No. C24 (7.5 A) fuse.

10. Open wire check (FAN LO SIGNAL line).

1. Turn the vehicle to the OFF (LOCK) mode.
2. Connect the HDS to the DLC.
3. Turn the vehicle to the ON mode.
4. Make sure the HDS communicates with the vehicle. If it does not communicate, go to the DLC circuit troubleshooting.
5. Turn the vehicle to the OFF (LOCK) mode.
6. Jump the SCS line with the HDS.

NOTE: This step must be done to protect the PCM from damage.

SCS Short

7. Disconnect the following connector.

PCM connector A (51P)

8. Check for continuity between test points 1 and 2.

Is there continuity?

YES

Go to step 11.

NO

Repair an open in the FAN LO SIGNAL wire between the radiator fan relay and the PCM.

11. Open wire check (IGP2 SUB line).

1. Connect the PCM connector.
2. Turn the vehicle to the ON mode.
3. Measure the voltage between test points 1 and 2.

Is there battery voltage?

YES

Go to step 12.

NO

Repair an open in the IGP2 SUB wire between the fan control relay and the No. B31 (7.5 A) fuse and/or the No. B31 (7.5A) fuse and the ETCS control relay.

12. Open wire check (FAN HI SIGNAL line).

1. Disconnect the following connector.

PCM connector A (51P)

2. Check for continuity between test points 1 and 2.

Is there continuity?

YES

Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If the PCM was substituted, and the symptom/indication goes away, replace the original PCM.

NO

Repair an open in the FAN HI SIGNAL wire between the fan control relay and the PCM.

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