2005 PILOT - Multiplex Control System Mode 1 Troubleshooting
2005 PILOT - Multiplex Control System Mode 1 Troubleshooting
Special Tools Required
MPCS service connector 07WAZ-001010A
Mode 1
Description:
Mode 1 is a communication line and CPU self test. If a problem occurs on a communication wire or with an individual control unit the multiplex system will store a DTC as long as the fault is still present.
To Enter Mode 1:
- Check the No. 9 (10 A) fuse in the driver's under-dash fuse/relay box and the No. 13 (7.5 A) fuse in the passenger's under-dash fuse/relay box.
Are the fuses OK?
YES- / Go to step 2.NO- / Find and repair the cause of the blown fuse.
- Connect the special tool to the multiplex control inspection connector (A).
- Turn the ignition switch ON (II). If the driver's seat belt is unbuckled, the seat belt reminder will beep five times.
- After about 5 seconds, the ignition key light should come on and the beeper should beep for 2 seconds, go off for 0.2 seconds, then blink and beep for 0.2 second. This means that you are in Mode 1 of the self-diagnosis function. Check self-diagnosis function Mode 1 for a diagnostic trouble code (DTC).
Did the multiplex system enter Mode 1?
YES- / Go to step 5.NO- / Go to step 6.
MODE 1: Ignition Key Light and Beeper
- Check for a DTC.
- If there are no DTCs present:
The ignition key light and beeper will not blink/beep again after the Mode 1 indication.
- If there is a DTC present:
About 1 second after entering Mode 1, the ignition key light and beeper indicate the DTC(s), then repeat it every 3 seconds. If there is more than one DTC, the system will indicate them in succeeding order.
Is there a DTC present?
YES- / Follow the procedure in the chart below.
NO- / Go to Mode 2.
DTC(s) / Cause / Procedure
1 / The driver's unit is not able to receive signals from the door unit. / Go to BRN wire communication line test.
2 / The driver's unit is not able to receive signals from the passenger's unit. / Go to PNK wire communication line test.
3 / Malfunction in the driver's unit. / Go to multiplex control system input test, if all inputs are OK, replace driver's multiplex control unit.
4 / Signals from each unit do not match. / Confirm correct multiplex control units are installed.
5 / The passenger's unit is not able to receive signals from the other units. / Go to multiplex control system input test, if all inputs are OK, replace passenger's multiplex control unit.
6 / The door unit is not able to receive signals from the other units. / Go to multiplex control system input test, if all inputs are OK, replace door multiplex control unit.
1, 2 and 3 Simultaneously / Communication (BRN or PNK) wire is shorted, (12 V or Ground). / Go to shorted communication line test.
- Remove the special tool from the MPCS inspection connector.
- Remove driver's multiplex control unit from the driver's under-dash fuse/relay box.
- Check for voltage between the A24 terminal of the driver's under-dash fuse/relay box socket and body ground.
Is there battery voltage?
YES- / Go to step 9.NO- / Replace the driver's under-dash fuse/relay box.
- Turn the ignition switch ON (II).
- Check for voltage between A12 terminal of the driver's under-dash fuse/relay box socket and body ground.
Is there battery voltage?
YES- / Go to step 11.NO- / Repair an open in the wire between No. 13 (7.5 A) fuse in the passenger's under-dash fuse/relay box and driver's under-dash fuse/relay box socket.
- Check for continuity between A14 terminal of the driver's under-dash fuse/relay box socket and body ground.
Is there continuity?
YES- / Go to step 12.NO- / Repair an open in the wire between driver's multiplex control unit connector and body ground. If the wire is OK, check for poor ground at G401.
- Check for continuity between the B11 terminal of the driver's multiplex control unit connector and body ground.
Is there continuity?
YES- / Go to step 13.NO- / Repair an open in the wire between the driver's multiplex control unit connector and body ground. If the wire is OK, check for poor ground at G501.
- Check for continuity between the No. 3 terminal of the MPCS inspection connector and the A15 terminal of the driver's under-dash fuse/relay box socket.
Is there continuity?
YES- / Go to step 14.NO- / Faulty driver's under-dash fuse/relay box internal circuit between the inspection connector and the driver's under-dash fuse/relay box. Replace the driver's under-dash fuse/relay box.
- Check for continuity between the No. 1 terminal of the multiplex control inspection connector and body ground.
Is there continuity?
YES- / If there is still no mode 1 indication, replace the driver's multiplex control unit and recheck the symptom.NO- / Repair an open in the wire between the inspection connector and body ground. If the wire is OK, check for a poor ground at G401.