Multiplex Integrated Control System: Diagnosis Honda Pilot II

Troubleshooting CAN Circuit Related Problems

Note. Check the PCM for DTCs and troubleshoot PCM (see GENERAL TROUBLESHOOTING INFORMATION ) or F-CAN loss of communication errors first.

How to clear the DTC

While in DTC indication status, press and hold down the select/reset button for more than 10 seconds.

1. Enter the B-CAN System Diagnosis Test Mode 1 (see ).
2. While in Test Model 1, press and hold down the SEL/RESET button for at least 10 seconds to clear the DTCs.

Loss of Communication DTC Cross-Reference Table

When an ECU is unable to communicate with the other ECUs on the CAN circuit, the other control units will set loss of communication DTCs. Use this table to find the control unit that is not communicating.

1. Find the Transmitting Control Unit that is in the same row as all of the loss of communication DTCs retrieved.
2. Do the input test for the transmitting control unit. CONTROL UNIT REFERENCE TABLE DTC type Related Unit MICU Gauge control module Door multiplex control unit Immobilizer-keyless control unit Climate control unit Automatic lighting control unit Power seat control unit Parking and back-up sensor control unit Power tailgate control unit HandsFreeLink control unit BUS OFF U1280 U1280 U1280 U1280 U1280 U1280 U1280 U1280 U1280 U1280 ECU (CPU) Error - - - B1901 - - - B2601 - - ECU (EE-PROM) Error B1002 B1152 - B1902 - B1552 B1802 B2602 B1352 B1792

CONTROL UNIT REFERENCE TABLE

DTC Troubleshooting Index

Note. Record all DTCs, and sort them by DTC type using the DTC troubleshooting index, then troubleshoot the DTC(s) in this order

1. Battery voltage DTCs
2. Internal error DTCs
3. Loss of communication DTCs (beginning with the lowest number first; for example, if B1036 and B1037 are retrieved, troubleshoot B1036 first).
4. Signal error DTCs

Test Mode 1

Check the PCM for DTCs and troubleshoot PCM (see GENERAL TROUBLESHOOTING INFORMATION ) or F-CAN loss of communication errors first, then perform this diagnosis if the HDS is not available.

1. Check the No. 23 (10 A) fuse in the under-hood fuse/relay box and the No. 10 (7.5 A) fuses in the under-dash fuse/relay box. Are the fuses OK? YES - Go to step 2 . NO - Find and repair the cause of the blown fuse.
2. Turn the ignition switch to ON (II), and move the interior light switch to the middle (door) position.
3. Connect the MPCS service connector (A) to the MICU service check connector socket (B) in the under-dash fuse/relay box.
4. Wait 5 seconds, and watch the individual map lights. When the lights flash quickly once, and then go off, the system is in Test Mode 1.
5. Check for B-CAN DTCs indicated by the gauge control module LCD display while still in Test Mode 1. Push the odometer select/reset button to display the next code. After you get to the last code, the display shows END. If no DTCs are stored, the display will read NO. Are any DTCs indicated? YES - Go to Step 6 . NO - Go to Step 9 .
6. Record all DTCs and sort them.
7. Troubleshoot the DTCs in this order: Battery voltage DTCs Internal error DTCs Loss of communication DTCs. Signal error DTCs
8. Clear the DTCs by pressing and holding the select/reset button for about 10 seconds. You will hear a beep to confirm the codes have been cleared. Operate the devices that failed, and recheck for codes. Test Mode 2
9. Remove the MPCS service connector from the under-dash fuse/relay box socket for 5-10 seconds, then re-insert it to enter Mode 2. When the system enters Mode 2, the ceiling light will flash two times quickly and then go off. NOTE: If the MPCS connector is disconnected for too short or too long of a time, or the ignition switch is turned to LOCK (0), the system will return to Test Mode 1.
10. The following tables list the circuits that can be checked in Test Mode 2. Operate the switch that is most closely related to the problem. If the circuit is OK, the individual map lights will blink once. If the circuit is faulty, there will be no indication. SWITCH REFERENCE TABLE Item Brake pedal position switch (ON) Driver's door switch Front passenger's door switch Left rear door switch Right rear door switch Tailgate latch switch (without PTG) Full latch switch (with PTG) Tailgate outer handle switch Left rear door lock knob switch (UNLOCK) Right rear door lock knob switch (UNLOCK) Audio unit (security input) Windshield wiper HI/LO switch Windshield wiper INT/LO switch Windshield wiper MIST switch Windshield washer switch Windshield wiper intermittent dwell time controller Windshield wiper motor park position (Auto stop) Rear window wiper switch Rear window washer switch Rear window wiper motor park position (Auto stop) Turn signal switch (LEFT) Turn signal switch (RIGHT) Hazard warning switch Headlight switch (ON) Headlight switch (OFF) Lighting switch Dimmer switch Passing switch Fog light switch Transmission range switch (P) Ignition key switch Security Hood switch Transmission range switch (R) Rear window wiper motor rise/return switch Hatch glass opener switch Driver's door hatch glass opener switch Hatch glass latch switch Do the individual map lights blink, indicating proper switch operation? YES - Go to function and input test for the system related to the failure. • NO - Repair the open, short, or replace the faulty switch.

Sleep and Wake-up Mode Test

1. Shift to the sleep mode: Turn the ignition switch to LOCK (0), open and close the driver's door. If the MICU receives no signals from the inputs listed below, it will go into sleep mode in less than 40 seconds. SWITCH REFERENCE TABLE B-CAN data Hazard warning switch (OFF) Hatch glass opener switch (OFF) Driver's door hatch grass opener switch (OFF)
2. Confirm the sleep mode: NOTE: Check for any official Honda service website for mor service information about parasitic draw at the battery. Check the parasitic draw at the battery while shifting into the sleep mode; amperage should change from about 200 mA to less than 35 mA in less that 50 seconds.
3. Shift to the wake up mode: When the ignition switch is turned to ON (II), the MICU, and all B-CAN system components wake up. When any switch in the multiplex integrated control system is turned on, a message is sent to the related control unit(s) to command the desired function. After confirming the sleep mode, look in the following table for the switch most related to the problem. Operate that switch and see if its control unit wakes up. NOTE: If any control unit is faulty and will not wake up, several circuits in the system will malfunction at the same time. In the table, the control unit is followed by a list of the switches and input signals that can wake it up. SWITCH REFERENCE TABLE B-CAN data Door switches (door open) Left rear door lock knob switch Right rear door lock knob switch Tailgate latch switch or full latch switch (Tailgate open) Tailgate outer handle switch (ON) Hatch glass latch switch (hatch glass open) Hatch glass opener switch (ON) Driver's door hatch glass opener switch (ON) Security Hood switch (hood open) Audio unit switch Hazard warning switch (ON) Combination light switch (Parking, Headlight, Dimmer, Passing ON) Ignition key switch (key inserted)

Scheme 4

Scheme 5

Control Unit Input Test

Note. Before testing, troubleshoot the multiplex integrated control unit first, using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ), and make sure the lighting system works properly.

Scheme 6

1. Turn the ignition switch to LOCK (0).
2. Remove the driver's dash board lower cover (see «DRIVER'S DASHBOARD LOWER COVER REMOVAL/INSTALLATION»(ref-333587-S27385002872009072100000) ).
3. Disconnect under-dash fuse/relay box connectors E, F, K, P, Q, R and T. NOTE: All connector views are shown from the wire side of female terminals.
4. 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 5 .
5. With the connectors still disconnected, do these input tests at the following 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 6 . WIRE TEST CONDITION REFERENCE TABLE Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained Q7 LT BLU Under all conditions Check for continuity between terminal Q7 and the data link connector 16P connector terminal No. 7: There should be continuity. An open in the K-LINE wire Check for continuity to body ground: There should be no continuity. A short to ground in the wire T12 WHT Immobilizer-keyless control unit 7P connector disconnected Check for continuity between terminal T12 and immobilizer-keyless control unit 7P connector terminal No. 4: There should be continuity. An open in the B-CAN wire T29 LT GRN Check for continuity between terminal T29 and immobilizer-keyless control unit 7P connector terminal No. 3: There should be continuity. An open in the B-CAN wire T12 WHT Gauge control module 32P connector disconnected Check for continuity between terminal T12 and gauge control module 32P connector terminal No. 20: There should be continuity. An open in the B-CAN wire T29 LT GRN Check for continuity between terminal T29 and gauge control module 32P connector terminal No. 19: There should be continuity. An open in the B-CAN wire T12 WHT HandsFreeLink control unit 28P connector disconnected Check for continuity between terminal T12 and HandsFreeLink control unit 28P connector terminal No. 18: There should be continuity. An open in the B-CAN wire T29 LT GRN Check for continuity between terminal T29 and HandsFreeLink control unit 28P connector terminal No. 17: There should be continuity. An open in the B-CAN wire T12 (1) WHT Parking and back-up sensor control unit 16P connector disconnected Check for continuity between terminal T12 and parking and back-up sensor control unit 16P connector terminal No. 7: There should be continuity. An open in the B-CAN wire T29 (1) LT GRN Check for continuity between terminal T29 and parking and back-up sensor control unit 16P connector terminal No. 6: There should be continuity. An open in the B-CAN wire T12 WHT Automatic lighting control unit 14P connector disconnected Check for continuity between terminal T12 and automatic lighting control unit 14P connector terminal No. 4: There should be continuity. An open in the B-CAN wire T29 LT GRN Check for continuity between terminal T29 and automatic lighting control unit 14P connector terminal No. 3: There should be continuity. An open in the B-CAN wire T12 WHT Door multiplex control unit 37P connector disconnected Check for continuity between terminal T12 and door multiplex control unit 37P connector terminal No. 35: There should be continuity. An open in the B-CAN wire T29 LT GRN Check for continuity between terminal T29 and door multiplex control unit 37P connector terminal No. 33: There should be continuity. An open in the B-CAN wire T12 (2) WHT Power tailgate control unit connector C 14P-disconnected Check for continuity between terminal T12 and Power tailgate control unit connector C 14P terminal No. 7: There should be continuity. An open in the B-CAN wire T29 (2) LT GRN Check for continuity between terminal T29 and Power tailgate control unit connector C 14P terminal No. 6: There should be continuity. An open in the B-CAN wire T12 (3) WHT Power seat control unit connector B (40P) disconnected Check for continuity between terminal T12 and Power seat control unit connector B (40P) terminal No. 40: There should be continuity. An open in the B-CAN wire T29 (3) LT GRN Check for continuity between terminal T29 and Power seat control unit connector B (40P) terminal No. 39: There should be continuity. An open in the B-CAN wire T12 WHT Climate control unit connector A (36P) disconnected (5) Check for continuity between terminal T12 and climate control unit connector A (36P) terminal No. 35: There should be continuity. An open in the B-CAN wire T29 LT GRN Check for continuity between terminal T29 and climate control unit connector A (36P) terminal No. 36: There should be continuity. An open in the B-CAN wire T12 WHT HVAC control unit connector A (24P) disconnected (6) Check for continuity between terminal T12 and HVAC control unit connector A (24P) terminal No 23: There should be continuity. An open in the B-CAN wire T29 LT GRN Check for continuity between terminal T29 and audio unit connector A (24P) terminal No. 24: There should be continuity. An open in the B-CAN wire T12 WHT Audio unit connector D (20P) disconnected Check for continuity between terminal T12 and audio unit connector D (20P) terminal No. 18: There should be continuity. An open in the wire T29 LT GRN Check for continuity between terminal T29 and audio unit connector D (20P) terminal No. 8: There should be continuity. An open in the B-CAN wire (1) With parking and back-up sensor system (2) With Power tailgate (3) With DPMS (4) With parking and back-up sensor system (5) With Climate control system (6) Without Climate control system
6. Reconnect the connectors to the under-dash fuse/relay box, and do these input tests at the following 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 7 . WIRE TEST CONDITION REFERENCE TABLE Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained P5 WHT Under all conditions Measure the voltage to ground: There should be battery voltage. Blown No. 23 (10 A) fuse in the under-hood fuse/relay box An open in the wire Faulty under-dash fuse/relay box P10 YEL Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage. Blown No. 10 (7.5 A) fuse in the under-dash fuse/relay box An open in the wire Faulty under-dash fuse/relay box K2 PUR Ignition switch ACC (I) Measure the voltage to ground: There should be battery voltage. Blown No. 35 (10 A) fuse in the under-dash fuse/relay box An open in the wire Faulty under-dash fuse relay box Faulty acc cut relay E6 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V. Poor ground (G401) An open in the wire T34 F20 Poor ground (G501) An open in the wire Power Window Master Switch (Door Multiplex Control Unit)
7. Turn the ignition switch to LOCK (0), then remove the power window master switch (see «POWER WINDOW MASTER SWITCH REPLACEMENT»(ref-333619-S07541619552009072100000) ).
8. Disconnect the 37P connector (A) from the power window master switch (B).
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. Reconnect the connector to the power window master switch, and do these input. 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 11 . WIRE TEST CONDITION REFERENCE TABLE Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained 13 WHT Under all conditions Measure the voltage to ground: There should be battery voltage. Blown No. 23 (10 A) fuse in the under-hood fuse/relay box An open in the wire Faulty under-dash fuse/relay box 32 BLK Under all conditions Measure the voltage to ground: There should be less than 0.2 V. Poor ground (G401) An open in the wire
11. If multiple failures are found on more than one control unit, replace the under-dash fuse/relay box (includes the MICU) (see «REMOVAL AND INSTALLATION»(ref-333607-S23852302332009072100000) ). If input failures are related to a particular control unit, replace the control unit.