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Home >> Acura >> 2004 >> MDX Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 67 (Multiplex Integrated Control System) >> Troubleshooting - B-CAN System Diagnosis Test Mode 1 and Test Mode 2 (without the HDS) >> Test Mode 1
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Test Mode 1

WARNING: This page is about a different car, the 2009 Acura MDX, 2008 Acura MDX, and 2007 Acura MDX. However, it is still accessible from the selected car via links, so may be relevant.

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. 7 (10 A) and No. 21 (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. Remove the left kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS ).
  3. Turn the ignition switch ON (II), and move the ceiling light switch to the middle (door) position.
  4. Connect the MPCS service connector (A) to the MCIC socket (B) in the under-dash fuse/relay box.
    Fig 1: Identifying MPCS Service Connector And MCIC Socket
    G05487856Courtesy of AMERICAN HONDA MOTOR CO., INC.
  5. Wait 5 seconds, and watch the ceiling lights. When the ceiling lights flash quickly once, and then go off, the system is in Test Mode 1.
  6. 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 7.

    NO  - Go to Step  10.

  7. Record all DTCs and sort them.
  8. Troubleshoot the DTCs in this order:
    • Battery voltage DTCs
    • Internal error DTCs
    • Loss of communication DTCs (begin with the lowest number first; for example, if B1008 and B1011 are retrieved, troubleshoot B1008 first). Refer to less of communication DTC cross reference chart (see LOSS OF COMMUNICATION DTC CROSS-REFERENCE CHART  ).
    • Signal error DTCs
  9. 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 

  10. 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 OFF, the system will return to Test Mode 1.
  11. 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 ceiling lights will blink once. If the circuit is faulty, there will be no indication.

MICU 

MICU REFERENCE

Item
Driver's door switch (OPEN)
Front passenger's door switch (OPEN)
Left rear door switch (OPEN)
Right rear door switch (OPEN)
Audio security ground (when disconnected)
Mirror select switch (LEFT, CENTER, RIGHT)
Mirror switch (LEFT, RIGHT, UP, DOWN)
* The front passenger's and door lock knob switches must be in the locked position when beginning the test.

RELAY CONTROL MODULE 

RELAY CONTROL MODULE REFERENCE

Item
Windshield wiper switch (AUTO STOP/PARK)
Hood switch (OPEN)

COMBINATION SWITCH CONTROL UNIT 

COMBINATION SWITCH CONTROL UNIT REFERENCE

Item
Turn signal switch (LEFT)
Turn signal switch (RIGHT)
Combination light switch (ON; each position)
Dimmer switch (ON)
Passing switch (ON)
Windshield wiper switch (ON)
Intermittent wiper dwell timer
Windshield washer switch (ON)
Fog light switch (ON)
Rear window wiper switch (ON)
Rear window washer switch (ON)

REAR MICU 

REAR MICU REFERENCE

Item
Tailgate latch switch (ON)
Tailgate outer handle switch (Without power tailgate) (ON)

DRIVER'S MPCS UNIT 

DRIVER'S MPCS UNIT REFERENCE

Item
Power window master switch (Driver's window UP)
Power window master switch (Driver's window DOWN)
Power window master switch (Driver's window AUTO UP)
Power window master switch (Driver's window AUTO DOWN)
Power window master switch (Front passenger's window UP)
Power window master switch (Front passenger's window DOWN)
Power window master switch (Front passenger's window AUTO UP)
Power window master switch (Front passenger's window AUTO DOWN)
Power window master switch (Left rear window UP)
Power window master switch (Left rear window DOWN)
Power window master switch (Right rear window UP)
Power window master switch (Right rear window DOWN)
Driver's door key cylinder switch(1) (LOCK)
Driver's door key cylinder switch(1) (UNLOCK)
Driver's door lock switch (LOCK)
Driver's door lock switch (UNLOCK)
Driver's door lock knob switch (LOCK)
Driver's door lock knob switch (UNLOCK)
Left rear door lock knob switch (2) (UNLOCK)
Driving position memory switches (1,2, memo)
Left rear power window switch (UP)
Left rear power window switch (DOWN)
Fuel fill door opener switch (ON)
(1) A second key is necessary to check the key cylinder inputs. Be sure to rotate the key cylinder switch two times to each position (lock and lock, unlock and unlock) to ensure the door lock knob switch is in the appropriate position.
(2) The left rear door lock knob switches must be in the locked position when beginning the test.

GAUGE CONTROL MODULE 

GAUGE CONTROL MODULE REFERENCE

Item
Parking brake switch (ON; parking brake applied)
Cruise control main SET/RESUME/CANCEL switch (ON; switch pressed)
Transmission range switch (P, R, N, D)
Washer fluid level switch (fluid removed) (Canada)
Brake fluid level switch (fluid removed)
Illumination control switches (+, -)
MID switches (Select/Reset, < INFO, INFO >)

POWER SEAT CONTROL UNIT 

POWER SEAT CONTROL UNIT REFERENCE

Item
Power seat slide switch (FORWARD, BACKWARD)
Power seat front up-down switch (UP, DOWN)
Power seat rear up-down switch (UP, DOWN) Power seat recline switch (FORWARD, RECLINE)
Power tilt/telescopic steering switch (UP, DOWN, PUSH, PULL)

FRONT PASSENGER'S MPCS UNIT 

FRONT PASSENGER'S MPCS UNIT REFERENCE

Item
Front passenger's door lock knob switch (1) (UNLOCK)
Right rear door lock knob switch (1) (UNLOCK)
Front passenger's door lock switch (LOCK)
Front passenger's door lock switch (UNLOCK)
Front passenger's power window switch (UP, DOWN, AUTO)
Right rear power window switch (UP, DOWN)
(1) The front passenger's and right rear door lock knob switches must be in the locked position when beginning the test.

Do the map lights indicate 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.

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