LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Isuzu >> 1996 >> Hombre XS >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Basic Testing >> Trouble Shooting >> Malfunction Indicator Light On Steady
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Malfunction Indicator Light On Steady

  1. Perform On-Board Diagnostic (OBD) System Check. See ON-BOARD DIAGNOSTIC (OBD) SYSTEM CHECK  . After performing OBD system check, go to next step.
  2. Turn ignition on with engine off. If Malfunction Indicator Light (MIL) illuminates, go to next step. If MIL does not illuminate, go to NO MALFUNCTION INDICATOR LIGHT  .
  3. Turn ignition off. Install scan tool. Turn ignition on with engine off. If scan tool powers up, go to next step. If scan tool does not power up, go to step 7).
  4. Using scan tool, command MIL ON and OFF. If MIL turns on and off as commanded, go to step 6). If MIL does not turn on and off as commanded, go to next step.
  5. Turn ignition off. Disconnect PCM connector C3. Turn ignition on with engine off. If MIL does not illuminate, go to step 14). If MIL illuminates, go to step 19).
  6. Turn ignition on. Disconnect scan tool. Connect test light between ground and DLC terminal No. 2 (Purple wire). If test light illuminates, go to step 9). If test light does not illuminate, go to step 8).
  7. Disconnect scan tool. Connect test light between ground and DLC terminal No. 16 (Orange wire). If test light illuminates, go to step 10). If test light does not illuminate, go to step 11).
  8. Connect test light to battery voltage. Probe DLC terminal No. 2 (Purple wire) with test light. If test light illuminates, go to step 13). If test light does not illuminate, go to step 12).
  9. Check serial data circuit at DLC terminal No. 2 (Purple wire) for short to voltage. Repair as necessary. After repairs, go to step 20). If circuit is okay, go to step 14).
  10. Connect test light to battery voltage. Probe test light to DLC terminals No. 4 (Black wire) and No. 5 (Black/White wire). If test light illuminates at both terminals, go to step 18). If test light does not illuminate at both terminals, go to step 15).
  11. Repair open or short to ground in battery feed circuit to DLC terminal No. 16 (Orange wire). After repairs, go to step 20).
  12. Check for an open in serial data circuit (Purple wire). Repair as necessary. After repairs, go to step 20). If circuit is okay, go to step 16).
  13. Check for short to ground in serial data circuit to DLC terminal No. 2 (Purple wire). Repair as necessary. After repairs, go to step 20). If circuit is okay, go to next step.
  14. Replace PCM. After replacing PCM, go to step 20).
  15. Repair open in appropriate ground circuit to DLC terminal No. 4 (Black wire) or No. 5 (Black/White wire). After repairs, go to step 20).
  16. Reinstall scan tool. If scan tool communicates with PCM, go to step 20). If scan tool cannot communicate with PCM, go to next step.
  17. Install scan tool on a known good vehicle. If scan tool works, go to step 14). If scan tool does not work, go to next step.
  18. Replace faulty scan tool and proceed to step 20).
  19. Check for short to ground in MIL control circuit to PCM connector C3 terminal No. 19 (Brown/White wire). After repairs, go to next step.
  20. Using scan tool, clear DTC(s). Attempt to start engine. If engine starts and continues to run, go to next step. If engine does not start or starts and dies/stalls, go to step 1).
  21. Warm engine to normal operating temperature. Check if any DTCs are set. If no DTCs are set, system is operating properly. If any DTCs are set, go to appropriate TESTS W/CODES article.
scientia non olet · About LEMON Manuals