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.
2007 Honda Pilot 2WD V6-3.5LFACTORY OEM SERVICE PROCEDURE
Multiplex Control Unit Input Test
Multiplex Control Unit Input Test
Before performing the multiplex control unit input test, do the multiplex troubleshooting (Mode 1 and Mode 2).
Passenger's Unit
1. Remove the passenger's multiplex control unit from the passenger's under-dash fuse/relay box.
2. Inspect the connector and socket terminals to be sure they are all making good contact.
- If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.
- If the terminals look OK, go to step 3.
3. Make the following input tests at the 22P connector B and the passenger's under-dash fuse/relay box socket connector A. Be careful not to spread the fuse box connectors.
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, go to step 4.
Door Unit
4. Carefully pry off the driver's door switch trim.
5. Disconnect the connectors (A).
6. Inspect the connector and socket terminals to be sure they are all making good contact.
- If the terminals are bent, loose or corroded, repair them as necessary, and re check the system.
- If the terminals look OK, go to step 7.
7. Make the following input tests at connector A (20P).
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, go to step 8.
Driver's Unit
8. Remove the driver's multiplex control unit from the driver's under-dash fuse/relay box.
9. Inspect the connector and socket terminals to be sure they are all making good contact.
- If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.
- If the terminals look OK, go to step 10.
10. Make the following input tests at 22P connector B and the driver's under-dash fuse/relay box socket connector A. Be careful not to spread the fuse box connectors.
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, one of the multiplex control units (door, driver's or passenger's) must be faulty. Substitute a known-good control unit for the one that's is most closely related to the failure, then recheck. If the symptom continues, replace the next most likely control unit until the symptom goes away.
Before performing the multiplex control unit input test, do the multiplex troubleshooting (Mode 1 and Mode 2).
Passenger's Unit
1. Remove the passenger's multiplex control unit from the passenger's under-dash fuse/relay box.
2. Inspect the connector and socket terminals to be sure they are all making good contact.
- If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.
- If the terminals look OK, go to step 3.
3. Make the following input tests at the 22P connector B and the passenger's under-dash fuse/relay box socket connector A. Be careful not to spread the fuse box connectors.
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, go to step 4.
Door Unit
4. Carefully pry off the driver's door switch trim.
5. Disconnect the connectors (A).
6. Inspect the connector and socket terminals to be sure they are all making good contact.
- If the terminals are bent, loose or corroded, repair them as necessary, and re check the system.
- If the terminals look OK, go to step 7.
7. Make the following input tests at connector A (20P).
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, go to step 8.
Driver's Unit
8. Remove the driver's multiplex control unit from the driver's under-dash fuse/relay box.
9. Inspect the connector and socket terminals to be sure they are all making good contact.
- If the terminals are bent, loose or corroded, repair them as necessary, and recheck the system.
- If the terminals look OK, go to step 10.
10. Make the following input tests at 22P connector B and the driver's under-dash fuse/relay box socket connector A. Be careful not to spread the fuse box connectors.
- If any test indicates a problem, find and correct the cause, then recheck the system.
- If all the input tests prove OK, one of the multiplex control units (door, driver's or passenger's) must be faulty. Substitute a known-good control unit for the one that's is most closely related to the failure, then recheck. If the symptom continues, replace the next most likely control unit until the symptom goes away.
Factory Service Tools
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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.