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Power Mirror Control Unit Input Test/Replacement

NOTE: Before troubleshooting the DPMS, troubleshoot the multiplex integrated control system first using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).
  1. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  2. Remove the driver's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  3. Disconnect the 24P connector (A) from the power mirror control unit (B).
    Fig 1: Identifying 24P Connector And Power Mirror Control Unit
    G08067610Courtesy of AMERICAN HONDA MOTOR CO., INC.
  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. Reconnect the connector to the power mirror control unit, and do the following input tests:
    • 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.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    11 BRN Ignition switch ON (II), or power mode ON Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 12 (7.5 A) fuse in the driver's under-dash fuse/relay box
    • An open or high resistance in the wire
    24 WHT Under all conditions Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 15 (10 A) fuse in the under-hood fuse/relay box
    • An open or high resistance in the wire
    22 BLK In all ignition switch positions or all power modes Measure the voltage to ground:
    There should be less than 0.2 V.
    • Poor ground (G401)
    • An open or high resistance in the ground wire
    1
    •
    2    		 PNK
    •
    BLU    		 Ignition switch ON (II), or power mode ON, and mirror select switch in LEFT, then mirror down switch pressed Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 16 (7.5 A) fuse in the driver's under-dash fuse/relay box
    • Faulty power mirror switch
    • An open or high resistance in the wire
    8
    •
    9    		 LT
    •
    BLU GRY    		 Ignition switch ON (II), or power mode ON, and mirror select switch in RIGHT, then mirror down switch pressed Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 16 (7.5 A) fuse in the driver's under-dash fuse/relay box
    • Faulty power mirror switch
    • An open or high resistance in the wire
    10 ORN Ignition switch ON (II), or power mode ON, and mirror select switch in LEFT or RIGHT, then mirror up switch pressed Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 16 (7.5 A) fuse in the driver's under-dash fuse/relay box
    • Faulty power mirror switch
    • An open or high resistance in the wire
    7 LT BLU Ignition switch ON (II), or power mode ON Measure the voltage to ground:
    There should be about 5 V.
    • Faulty mirror position sensor
    • A short to ground in the wire
    4
    •
    6    		 YEL
    •
    GRN    		 Swing the left mirror from full left to full right Measure the voltage between terminals No. 4 and No. 6:
    There should be about 0.5 V to 4.5 V (average about 2.5 V when the mirror moves).
    • Faulty left mirror position sensor
    • An open or high resistance in the wire
    • A short to ground in the wire
    5
    •
    6    		 PUR
    •
    GRN    		 Move the left mirror from full up to full down Measure the voltage between terminals No. 5 and No. 6:
    There should be about 0.5 V to 4.5 V (average about 2.5 V when the mirror moves).
    • Faulty left mirror position sensor
    • An open or high resistance in the wire
    • A short to ground in the wire
    20
    •
    6    		 BLU
    •
    GRN    		 Swing the right mirror from full left to full right Measure the voltage between terminals No. 20 and No. 6:
    There should be about 0.5 V to 4.5 V (average about 2.5 V when the mirror moves).
    • Faulty right mirror position sensor
    • An open or high resistance in the wire
    • A short to ground in the wire
    19
    •
    6    		 ORN
    •
    GRN    		 Move the right mirror from full up to full down Measure the voltage between terminals No. 19 and No. 6:
    There should be about 0.5 V to 4.5 V (average about 2.5 V when the mirror moves).
    • Faulty right mirror position sensor
    • An open or high resistance in the wire
    • A short to ground in the wire
  6. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode, then disconnect the connectors from the power mirror control unit, and do the following input tests:
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, the control unit must be faulty; replace it.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    13 LT GRN Disconnect power seat control unit B (40P) connector Check for continuity between terminal No. 13 and power seat control unit B (40P) connector terminal No. 38:
    There should be continuity.    		 An open in the UART wire
    14
    •
    15    		 RED
    •
    GRN    		 Under all conditions Connect terminals No. 14 and No. 24, and terminals No. 15 and No. 22:
    The left mirror should move up.
    • Faulty left mirror actuator
    • An open or high resistance in the wire
    Connect terminals No. 15 and No. 24, and terminals No. 14 and No. 22:
    The left mirror should move down.
    15
    •
    16    		 GRN
    •
    PNK    		 Under all conditions Connect terminals No. 15 and No. 24, and terminals No. 16 and No. 22:
    The left mirror should swing left.
    • Faulty left mirror actuator
    • An open or high resistance in the wire
    Connect terminals No. 16 and No. 24, and terminals No. 15 and No. 22:
    The left mirror should swing right.
    3
    •
    17    		 BRN
    •
    WHT    		 Under all conditions Connect terminals No. 3 and No. 24, and terminals No. 17 and No. 22:
    The right mirror should move up.
    • Faulty right mirror actuator
    • An open or high resistance in the wire
    Connect terminals No. 17 and No. 24, and terminals No. 3 and No. 22:
    The right mirror should move down.
    17
    •
    18    		 WHT
    •
    PUR    		 Under all conditions Connect terminals No. 17 and No. 24, and terminals No. 18 and No. 22:
    The right mirror should swing left.
    • Faulty right mirror actuator
    • An open or high resistance in the wire
    Connect terminals No. 18 and No. 24, and terminals No. 17 and No. 22:
    The right mirror should swing right.
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