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.
PSP Switch Signal Circuit Troubleshooting
- Start the engine, and let it idle.
- Align the steering wheel straight ahead.
- Check the PSP SWITCH in the DATA LIST with the HDS.
Does it indicate ON?
YES -Go to step 4.
NO -Go to step 14.
- Turn the steering wheel to the full lock position.
- Check the PSP SWITCH in the DATA LIST with the HDS.
Does it change to OFF?
YES -The PSP switch signal circuit is OK.
NO -Go to step 6.
- Turn the ignition switch to LOCK (0).
- Disconnect the PSP switch 2P connector.
- Start the engine.
- Check the PSP SWITCH in the DATA LIST with the HDS.
Does it change to OFF?
YES -Replace the PSP switch.
NO -Go to step 10.
- Turn the ignition switch to LOCK (0).
- Jump the SCS line with the HDS.
- Disconnect ECM/PCM connector A (49P).
- Check for continuity between PSP switch 2P connector terminal No. 1 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Repair short in the wire between the ECM/PCM (A38) and the PSP switch.
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).
- Disconnect the PSP switch 2P connector.
- Connect PSP switch 2P connector terminals No. 1 and No. 2 with a jumper wire, then start the engine.
- Check the PSP SWITCH in the DATA LIST with the HDS.
Does it change to ON?
YES -Replace the PSP switch (see POWER STEERING HOSE, LINE, AND PRESSURE SWITCH REPLACEMENT ).
NO -Go to step 18.
- Turn the ignition switch to LOCK (0).
- Remove the jumper wire from the PSP switch 2P connector.
- Jump the SCS line with the HDS.
- Disconnect ECM/PCM connector A (49P).
- Check for continuity between ECM/PCM connector terminal A38 and PSP switch 2P connector terminal No. 1.Fig 3: Checking Continuity Between ECM/PCM Connector Terminal A38 And PSP Switch 2P Connector Terminal No. 1
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Go to step 23.
NO -Repair open in the wire between the PSP switch and the ECM/PCM (A38).
- Check for continuity between PSP switch 2P connector terminal No. 2 and body ground.
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -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 ).
NO -Repair open in the wire between the PSP switch and G201 (see RIGHT ENGINE COMPARTMENT WIRE HARNESS ).
NO RELATED
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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.