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DTC P1282: Fuel Pump Relay Control Circuit

NOTE: For connector terminal identification, see CONNECTOR IDENTIFICATION . For circuit identification and wiring diagram, see CHEROKEE wiring diagram in WIRING DIAGRAMS article.
NOTE: DTC P1282: FUEL PUMP RELAY CONTROL CIRCUIT is monitored with ignition on and battery voltage more than 10 volts. DTC may be stored in Powertrain Control Module (PCM) if PCM senses an open or short condition in fuel pump relay control circuit. Possible causes are: defective fuel pump relay, defective PCM, defective connector or defective wiring,
  1. Turn ignition on, with engine off. Using scan tool, actuate fuel pump relay. Fuel pump relay is located in Power Distribution Center (PDC). PDC is located next to battery. Refer to label under PDC cover for relay location. If fuel pump relay clicks, go to next step. If fuel pump relay does not click, go to step 4).
  2. Ensure ignition is on, with engine off. Wiggle wiring harness from fuel pump relay to PCM while actuating fuel pump relay. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. If fuel pump relay stops clicking at any time while wiggling wiring harness, repair wiring harness where wiggling caused fuel pump relay to stop clicking. Perform TEST VER-2A. If fuel pump relay does not stop clicking at any time while wiggling wiring harness, go to next step.
  3. Turn ignition off. Visually inspect related connectors and wiring harness. Repair connectors and wiring harness as necessary. Perform TEST VER-2A. If connectors and wiring harness are okay, go to next step.
  4. Ensure ignition is off. Remove fuel pump relay. Clean and/or repair connector as necessary. Using an ohmmeter, check resistance between fuel pump relay terminals No. 85 and 86. See Figure. If resistance is less than 100 ohms, go to next step. If resistance is 100 ohms or more, replace fuel pump relay. Perform TEST VER-2A.
  5. Ensure ignition is off. Ensure fuel pump relay is still removed. Turn ignition on, with engine off. Using a voltmeter, check voltage on fuel pump relay connector, fused ignition switch output circuit (Dark Blue/White wire). If voltage is more than 10 volts, go to next step. If voltage is 10 volts or less, repair open fused ignition switch output circuit. Perform TEST VER-2A.
  6. Ensure ignition is off. Ensure fuel pump relay is still removed. Disconnect PCM connectors. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. Clean and/or repair connectors as necessary. Using an ohmmeter, check resistance of fuel pump relay control circuit (Brown wire) between fuel pump relay and PCM. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open fuel pump relay control circuit. Perform TEST VER-2A.
  7. Ensure ignition is off. Ensure fuel pump and PCM connectors are still disconnected. Using ohmmeter, check resistance between ground and PCM connector, fuel pump relay control circuit (Brown wire). If resistance is less than 5 ohms, repair fuel pump relay control circuit for short to ground. Perform TEST VER-2A. If resistance is 5 ohms or more, go to next step.
  8. At this time, PCM is assumed to be defective. Replace PCM. Perform TEST VER-2A.
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