Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
MIL Circuit Troubleshooting
- Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
- Do the gauge self-diagnostic function (see
SELF-DIAGNOSTIC FUNCTION
).
Does the MIL flash?
YES - Go to step 3.
NO - Substitute a known-good gauge control module, and recheck. If the symptom/indication goes away with a known-good gauge control module, replace the original gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ). ■
- Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
- Check the SCS in the DATA LIST with the HDS.
Is a short indicated?
YES - Go to step 5.
NO - Update the ECM/PCM if it does not have the latest software (see ECM/PCM Update ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then recheck. If the symptom/indication goes away and the ECM/PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM/PCM was substituted, replace the original ECM/PCM (see ECM/PCM Replacement ). ■
- Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
- Disconnect ECM/PCM connector A (49P), then disconnect the HDS.
- Check for continuity between ECM/PCM connector terminal A32 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES - Repair short in the wire between the ECM/PCM (A32) and the DLC. ■
NO - Update the ECM/PCM if it does not have the latest software (see ECM/PCM Update ), or substitute a known-good ECM/PCM (see SUBSTITUTING THE ECM/PCM ), then recheck. If the symptom/indication goes away and the ECM/PCM was updated, troubleshooting is complete. If the symptom/indication goes away and the ECM/PCM was substituted, replace the original ECM/PCM (see ECM/PCM Replacement ). ■
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.