M/T
DTC P1520 - COOLING FAN RELAY 1 CIRCUIT HIGH INPUTDTC DETECTING CONDITION:
- Two consecutive driving cycles with fault
TROUBLE SYMPTOM:
- Radiator fan does not operate properly.
- Overheating
CAUTION: After repair or replacement of faulty parts, conduct CLEAR MEMORY MODE and INSPECTION MODE. Refer to How To Clear Diagnostic Trouble Codes.
Wiring Diagram:
WIRING DIAGRAM
10CN1: CHECK OUTPUT SIGNAL FROM ECM.
1. Turn ignition switch to OFF.
2. Connect test mode connector at the lower portion of instrument panel (on the driver's side), to the side of the center console box.
3. Turn ignition switch to ON.
Connector & Terminal - [(B134) No.3 (+) - Chassis Ground (-)]:
4. While operating radiator fan relay, measure voltage between ECM and chassis ground.
NOTE: Radiator fan relay operation can be executed using Subaru Select Monitor. For procedure, refer to "COMPULSORY VALVE OPERATION CHECK MODE".
CHECK: Does voltage change between 0 and 10 V?
YES: Even if MIL lights up, the circuit has returned to a normal condition at this time. In this case, repair poor contact in ECM connector.
NO: Go to step 10CN2.
10CN2: CHECK SHORT CIRCUIT IN RADIATOR FAN RELAY CONTROL CIRCUIT.
1. Turn ignition switch to OFF.
2. Remove main fan relay and sub fan relay. (with A/C models)
3. Disconnect test mode connector.
4. Turn ignition switch to ON.
Connector & Terminal - [(B134) No.3 (+) - Chassis Ground (-)]:
5. Measure voltage between ECM and chassis ground.
CHECK: Is the voltage more than 10 V?
YES: Repair battery short circuit in radiator fan relay control circuit. After repair, replace ECM.
NO: Go to step 10CN3.
10CN3: CHECK MAIN FAN RELAY.
1. Turn ignition switch to OFF.
2. Remove main fan relay.
Terminals - [No.1 - No.3]:
3. Measure resistance between main fan relay terminals.
CHECK: Is the resistance less than 1 Ohm?
YES: Replace main fan relay and ECM.
NO: Go to step 10CN4.
10CN4: CHECK SUB FAN RELAY.
1. Remove sub fan relay.
Terminals - [No.1 - No.3]:
2. Measure resistance between sub fan relay terminals.
CHECK: Is the resistance less than 1 Ohm?
YES: Replace sub fan relay and ECM.
NO: Go to step 10CN5.
10CN5: CHECK POOR CONTACT.
Check poor contact in ECM connector.
CHECK: Is there poor contact in ECM connector?
YES: Repair poor contact in ECM connector.
NO: Replace ECM.