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HOMESERVICE MANUALSSUBARU2002FORESTER BASEREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCETESTING & DIAGNOSISENGINE CONTROLS - SELF-DIAGNOSTICS - 2.5LDIAGNOSTIC TESTSP0691: COOLING FAN RELAY NO. 1 CIRCUIT LOW INPUT (LEGACY & OUTBACK)
2002 Subaru Forester Base

P0691: Cooling Fan Relay No. 1 Circuit Low Input (Legacy & Outback)

2002 Subaru Forester BaseSECTION P0691: Cooling Fan Relay No. 1 Circuit Low Input (Legacy & Outback)
NOTE: This diagnostic procedure is written for scan tool operation. Radiator fan relay can be operated by performing compulsory valve operation if Subaru Select Monitor is being used. See COMPULSORY VALVE OPERATION CHECK MODE  under SELF-DIAGNOSTIC SYSTEM.
  1. Perform test procedure. See TESTING PROCEDURE . Turn ignition off. Connect 2-pin Green test connector located under left side of instrument panel. See Figure. Turn ignition on. Using a scan tool, activate radiator fan relay. While activating radiator fan relay, use a DVOM to measure voltage of Red/Blue wire by backprobing between 35-pin ECM electrical harness connector B134 terminal No. 3 and good chassis ground point. See Figure. If voltage does not change between zero and 10 volts while activating radiator fan relay, go to next step. If voltage changes between zero and 10 volts while activating radiator fan relay, repair poor contact in ECM connector B134. Clear memory and perform verification procedure. See CLEARING DIAGNOSTIC TROUBLE CODES  and VERIFICATION PROCEDURE  .
  2. Turn ignition off. Disconnect 35-pin ECM electrical harness connector B134. Using a DVOM, measure resistance of Red/Blue wire between 35-pin ECM electrical harness connector B134 terminal No. 3 and good chassis ground point. See Figure. If resistance is not less than 10 ohms, go to next step. If resistance is less than 10 ohms, locate and repair short to ground in radiator fan relay No. 1 control circuit. See COOLING FAN in appropriate SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Clear memory and perform verification procedure. See CLEARING DIAGNOSTIC TROUBLE CODES  and VERIFICATION PROCEDURE  .
  3. Turn ignition off. Remove main fan relay from fuse and relay holder located on left front fender in engine compartment. Turn ignition on. Using a DVOM, measure voltage of Green/Black wire between main fan relay cavity No. 5 and good chassis ground. See Fig 1. If voltage is more than 10 volts, go to next step. If voltage is not more than 10 volts, locate and repair open circuit in wiring between ignition switch and fuse and relay holder. See COOLING FAN in appropriate SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Clear memory and perform verification procedure. See CLEARING DIAGNOSTIC TROUBLE CODES  and VERIFICATION PROCEDURE  .
  4. With main fan relay removed, measure resistance between relay terminals No. 5 and 6. If resistance is between 87 and 107 ohms, go to next step. If resistance is not between 87 and 107 ohms, replace main fan relay. Clear memory and perform verification procedure. See CLEARING DIAGNOSTIC TROUBLE CODES  and VERIFICATION PROCEDURE  .
  5. Using a DVOM, measure resistance of Red/Blue wire between 35-pin ECM electrical harness connector B134 terminal No. 3 and main fan relay cavity No. 6. See Figure and Fig 1 . If resistance is less than one ohm, go to next step. If resistance is not less than one ohm, locate and repair open circuit in wiring and check for poor terminal contact in all connectors between ECM and fuse and relay holder. See COOLING FAN in appropriate SYSTEM WIRING DIAGRAMS article in ELECTRICAL. Clear memory and perform verification procedure. See CLEARING DIAGNOSTIC TROUBLE CODES  and VERIFICATION PROCEDURE  .
  6. Check for poor terminal contact in ECM and main fan relay electrical harness connectors. Repair poor contact as necessary. If connectors are okay, contact authorized Subaru dealership. Clear memory and perform verification procedure. See CLEARING DIAGNOSTIC TROUBLE CODES  and VERIFICATION PROCEDURE  .
Fig 1: Locating Main Fan & Sub-Fan Relays (Legacy & Outback)
G00256579Courtesy of SUBARU OF AMERICA, INC.
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