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.
Power Steering Pressure Switch Signal: MDX
2004 Acura 3.5RLSECTION MDX
- Start engine and allow to idle. Align steering wheel straight ahead.
- With the Honda PGM-FI Tester or the HDS, monitor the PSP SWITCH in the DATA LIST. If OFF is indicated, go to next step. If OFF is not indicated, go to step . 4
- Turn steering wheel to full lock position. With the Honda PGM-FI Tester or the HDS, monitor the PSP SWITCH in the DATA LIST. If the indication is changed to ON, replace PSP switch, and recheck. If the indication is not changed to ON, go to next step.
- Turn ignition off. Disconnect PCM harness connector B. Check for continuity between ground and PSP switch 2-pin connector terminal No. 1 (Light Blue wire). If there is continuity, repair short in wire between PSP switch connector terminal No. 1 and PCM, then go to next step. If there is no continuity, update the PCM if it does not have the latest software. Substitute known-good PCM/ECM, then recheck. If symptom or indication goes away, replace original PCM/ECM.
- Turn ignition off. Disconnect PSP switch 2-pin connector. With a fused jumper wire, connect PSP switch 2-pin connector terminals No. 1 and 2. With the Honda PGM-FI Tester or the HDS, monitor the PSP SWITCH in the DATA LIST. If OFF is indicated, replace PSP switch, and recheck. If OFF is not indicated, go to next step.
- Turn ignition off. Disconnect PCM harness connector B. Check for continuity between PSP 2-pin harness connector No. 1 (Light Blue wire) and PCM harness connector terminal B55. If there is continuity, go to next step. If there is no continuity, repair open in wire between PSP switch connector and PCM, then recheck.
- Check for continuity between ground PSP switch connector terminal No. 2. If there is continuity, update the PCM if it does not have the latest software. Substitute known-good PCM, then recheck. If symptom or indication goes away, replace original PCM. If there is no continuity, repair open in wire between PSP switch connector terminal No. 2 and ground connector G503, then recheck.
RENDER: 1.0x
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.