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Home >> Mitsubishi >> 2000 >> Eclipse GT, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Circuit Tests >> Scan Tool Will Not Communicate >> No Communication With ECM/PCM (2.4L)
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No Communication With ECM/PCM (2.4L)

  1. Check wires and connectors between OBD-II Data Link Connector (OBD-II DLC) and Engine Control Module (ECM) 12-pin connector C-56, or Powertrain Control Module (PCM) 28-pin connector C-57. If problem exists, repair as necessary. If problem does not exist, go to next step.
  2. Check ECM connector C-56, or PCM connector C-57. Repair as necessary. If connector is okay, go to next step.
  3. Remove and check MFI relay. See FUEL PUMP RELAY & MFI RELAY under RELAYS under MOTORS, RELAY & SOLENOIDS in SYSTEM & COMPONENT TESTING article. Replace MFI relay as necessary. If MFI relay is okay, go to next step.
  4. Check voltage between ground and MFI relay connector terminals No. 3 and 4. If battery voltage exists at each terminal, install MFI relay, then go to next step. If battery voltage does not exist at both terminals, repair wiring between battery and MFI relay.
  5. Disconnect ECM 22-pin connector C-60, or PCM connector C-57. Turn ignition on. Check voltage between ground and ECM connector C-60 terminal No. 82, or PCM connector C-57 terminal No. 98. If battery voltage exists, go to next step. If battery voltage does not exist, check wire between ignition switch and ECM/PCM. Repair as necessary. If wiring is okay, check ignition switch.
  6. On A/T vehicles, turn ignition off and disconnect PCM 26-pin connector C-54. On all vehicles, turn ignition on. Check voltage between ground and ECM connector C-60 terminal No. 80, or PCM connector C-54 terminal No. 66. If battery voltage exists, go to next step. If battery voltage does not exist, repair wire between battery and ECM/PCM.
  7. Turn ignition off. On M/T vehicles, disconnect ECM 26-pin connector C-49. On all vehicles, check resistance between ground and ECM connector C-49 terminals No. 13 and 26, or PCM connector C-54 terminals No. 42 and 48. If each resistance is less than 2 ohms, go to next step. If either resistance is 2 ohms or more, repair appropriate wire between ground and ECM/PCM. Grounds are located in engine compartment near battery and near ECM/PCM.
  8. On M/T vehicles, disconnect ECM 16-pin connector C-53. On all vehicles, connect jumper wire between ground and ECM connector C-53 terminal No. 38, or PCM connector C-54 terminal No. 49. MFI relay should audibly click. Check voltage between ground and ECM connector C-49 terminals No. 12 and 25, or PCM connector C-54 terminals No. 41 and 47. If battery voltage exists at each terminal, go to next step. If battery voltage does not exist at either terminal, repair appropriate wire between MFI relay and ECM/PCM.
  9. Check ECM connectors C-49, C-53 and C-60, or PCM connectors C-54 and C-57. Repair as necessary. If connectors are okay, replace ECM/PCM.
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