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Test Ab: Malfunction Indicator Light Inoperative

NOTE: Malfunction Indicator Light (MIL) may also be referred to as SERVICE ENGINE SOON light.
  1. If powertrain control system diagnostic system check has been performed, go to next step. If powertrain control system diagnostic system check has not been performed, perform powertrain control system diagnostic system check. See POWERTRAIN CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  2. Attempt to start engine. If engine starts, go to next step. If engine does not start, go to step  9 .
  3. Check IGN 0, CLUSTER, PCM & BCM fuse (10-amp) in instrument panel fuse block. See Figure . Instrument panel fuse block is located behind right side instrument panel endcap. If fuse is not blown, go to next step. If fuse is blown, go to step  7 .
  4. Turn ignition switch to OFF position. Disconnect Powertrain Control Module (PCM) Natural harness connector C2. PCM is located in front left corner of engine compartment, inside air cleaner. Turn ignition switch to RUN position. Connect a fused jumper wire between ground and PCM harness connector C2 terminal No. 5 (Brown/White wire). See Figure . If MIL is not illuminated, go to next step. If MIL is illuminated, go to step  15
  5. Turn ignition switch to OFF position. Remove Instrument Panel Cluster (IPC). See INSTRUMENT PANEL CLUSTER  under REMOVAL & INSTALLATION. Connect a test light between ground and IPC harness connector terminal A8 (Purple wire). See Figure . If test light illuminates, go to next step. If test light does not illuminate, go to step  8 .
  6. Test Brown/White wire between IPC harness connector B5 and PCM Natural harness connector terminal No. 5 for an open or high resistance. See Figure and Figure . If an open or high resistance is not found, go to step  14 . If an open or high resistance is found, repair as necessary. After repair, return to POWERTRAIN CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  7. Repair short to ground in Purple wire between Instrument Panel Cluster (IPC) harness connector and instrument panel fuse block. See WIRING DIAGRAMS  . After repair, return to POWERTRAIN CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  8. Repair open in Purple wire between IPC harness connector and instrument panel fuse block. See WIRING DIAGRAMS  . After repair, return to POWERTRAIN CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  9. Check PCM, BCM, U/H RELAY fuse (10-amp) in instrument panel fuse block, and IGN 1 fuse (30-amp) in underhood accessory wiring junction block. See Figure and Figure . Instrument panel fuse block is located behind right side instrument panel endcap. Underhood accessory wiring junction block is located on right front strut tower. If neither fuse is blown, go to next step. If either fuse is blown, go to step  12
  10. Ensure ignition switch is in OFF position. Disconnect Powertrain Control Module (PCM) harness connectors. PCM is located in front left corner of engine compartment, inside air cleaner. Turn ignition switch to RUN position. Connect a test light between ground and in turn, PCM Blue harness connector C1 terminals No. 19 and 23 (Purple wires), and PCM Natural connector C2 terminal No. 24 (Pink wire). See Figure . If test light illuminates at each terminal, go to next step. If test light does not illuminate at each terminal, go to step  12 .
  11. Connect test light between ground and PCM harness connector C1 terminal No. 20 (Orange wire). If test light does not illuminate, go to next step. If test light illuminates, go to step  13 .
  12. Repair open or short to ground in appropriate wire. See WIRING DIAGRAMS  . After repair, return to POWERTRAIN CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  13. Check for poor connections between PCM harness connector C1 terminals No. 16, 56, 57 and 60 (Black/White wires) and ground point G113. Ground point G113 is located in lower left front of engine, on transaxle stud, to left of starter. If poor connections are not found, go to step  15 . If poor connections are found, repair as necessary. After repair, return to POWERTRAIN CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  14. Check for poor connections at IPC harness connector. If poor connections are not found, go to step  16 . If poor connections are found, repair as necessary. After repair, return to POWERTRAIN CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  15. Check for poor connections at Instrument Panel Cluster (IPC) harness connector. If poor connections are not found, go to step  17 . If poor connections are found, repair as necessary. After repair, return to POWERTRAIN CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  16. Replace IPC. See INSTRUMENT PANEL CLUSTER  under REMOVAL & INSTALLATION. After repair, return to POWERTRAIN CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
  17. Replace PCM. See POWERTRAIN CONTROL MODULE  under REMOVAL & INSTALLATION. After repair, return to POWERTRAIN CONTROL SYSTEM DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM.
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