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Home >> Saab >> 1991 >> 900 SPG >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Modules, Relays & Solenoids >> Relays >> Main Relay
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Main Relay

  1. Turn ignition off. Unplug connector from fuel injection ECU. Connect DVOM to terminal No. 5 (Brown/White wire) at mass airflow meter and ground. Using a jumper wire, ground harness connector terminals No. 20 (Violet wire) and No. 21 (Yellow/White wire). If fuel pump runs and DVOM indicates battery voltage, main relay is okay. If not, go to step 2).
  2. Remove jumper wires. Remove main relay. Relay is located on right kick panel, behind trim. Check for battery voltage at relay socket terminals No. 30 (Red wire) and No. 86 (Red wire). If no voltage, repair Red wires to main battery junction on battery bracket.
  3. Reinstall relay. Connect DVOM to relay terminal No. 87B (single Blue/Red wire on 900 Series; Green/White wire on 9000 Series) and ground. Using a jumper wire, ground terminal No. 85 (Yellow/White wire). Replace relay if DVOM does not indicate battery voltage.
  4. Leave jumper wire in place. Connect DVOM to relay terminal No. 87 (Blue/Red and Brown/White wires on 900 Series; Blue/Red wire on 9000 Series) and ground. Replace relay if DVOM does not indicate battery voltage.
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