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MICU Input Test

NOTE: Before testing, troubleshoot the multiplex integrated control system first, using B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

Driver's MICU 

  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 dashboard undercover (see DRIVER'S DASHBOARD UNDERCOVER REMOVAL/INSTALLATION ).
  3. Disconnect driver's under-dash fuse/relay box connectors F, Q, and R.
    NOTE: All connector views are wire side of female terminals.
    Fig 1: Identifying Driver'S Under-Dash Fuse/Relay Box Connectors F, Q, And R
    G08086855Courtesy 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. With the connectors still disconnected, 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
    F7
    .
    F30    		 ORN
    .
    GRN    		 Under all conditions Connect terminals F16 and F30, and terminal F7 to body ground with jumper wires: The windshield wiper motor should run at high speed.
    • Blown No. 3-7 (WIPER MTR) (30 A) fuse in the under-hood fuse/relay box
    • Faulty relay circuit board
    • Faulty windshield wiper motor
    • Poor ground (G303 and G202) or an open in the ground wire
    • An open or high resistance in the wire
    F8 YEL Run the windshield wiper motor by connecting terminals F16 and F30, and terminal F7 to body ground with jumper wires Connect terminal F8 to body ground with a jumper wire: The windshield wiper motor speed should change from high speed to low speed.
    • Faulty under-hood fuse/relay box
    • Faulty relay circuit board
    • Faulty windshield wiper motor
    • An open or high resistance in the wire
    F9 PNK Run the windshield wiper motor by connecting terminals F16 and F30, and terminal F7 to body ground with jumper wires Check for continuity to ground: The needle of the ohmmeter should pulse 1 time per wiper motor cycle.
    NOTE: Use a DVOM.
    • Faulty windshield wiper motor
    • Poor ground(G303)or an open in the ground wire
    • An open or high resistance in the wire
  6. Reconnect the connectors to the driver's under-dash fuse/relay box.
  7. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, 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 8.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    F20 LT GRN Brake pedal pressed Measure the voltage to ground: There should be battery voltage.
    • Blown No. 10 (15 A) fuse in the under-hood fuse/relay box
    • Faulty brake pedal position switch
    • An open or high resistance in the wire
    Brake pedal released Measure the voltage to ground: There should be no voltage.
    • Faulty brake pedal position switch
    • A short to power in the wire
    Q1 BRN 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
    Q2 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 (G402)
    • An open or high resistance in the ground wire
    R2 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(G402)
    • An open or high resistance in the ground wire
    R5 ORN 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
    F4 LT BLU Transmission range switch in P Measure the voltage to ground: There should be less than 0.2 V.
    • Faulty transmission range switch
    • Poor ground (G101) or an open in the ground wire
    • An open or high resistance in the wire
    Transmission range switch in any other position than P Measure the voltage to ground: There should be about 5 V.
    • Faulty transmission range switch
    • A short to ground in the wire
    R15
    .
    R4    		 ORN
    .
    BLK    		 Wiper switch (INT or LO) ON Measure the voltage between terminals R15 and R4: There should be less than 0.2 V.
    • Faulty windshield wiper/washer switch
    • An open or high resistance in the wire
    Wiper switch OFF Measure the voltage between terminals R15 and R4: There should be about 5 V.
    • Faulty windshield wiper/washer switch
    • A short to ground in the wire
    R16
    .
    R4    		 WHT
    .
    BLK    		 Wiper switch (LO or HI) ON Measure the voltage between terminals R16 and R4: There should be less than 0.2 V.
    • Faulty windshield wiper/washer switch
    • An open or high resistance in the wire
    Wiper switch OFF Measure the voltage between terminals R16 and R4: There should be about 5 V.
    • Faulty windshield wiper/washer switch
    • A short to ground in the wire
    R17
    .
    R4    		 GRN
    .
    BLK    		 Wiper switch (MIST) ON Measure the voltage between terminals R17 and R4: There should be less than 0.2 V.
    • Faulty windshield wiper/washer switch
    • An open or high resistance in the wire
    Wiper switch OFF Measure the voltage between terminals R17 and R4: There should be about 5 V.
    • Faulty windshield wiper/washer switch
    • A short to ground in the wire
    R18
    .
    R4    		 YEL
    .
    BLK    		 Washer switch ON Measure the voltage between terminals R18 and R4: There should be less than 0.2 V.
    • Faulty windshield wiper/washer switch
    • An open or high resistance in the wire
    Washer switch OFF Measure the voltage between terminals R18 and R4: There should be about 5 V.
    • Faulty windshield wiper/washer switch
    • A short to ground in the wire

    Passenger's MICU 

  8. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
  9. Remove the front passenger's kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS ).
  10. Disconnect passenger's under-dash fuse/relay box connectors A and E.
    NOTE: All connector views are wire side of female terminals.
    Fig 2: Identifying Passenger'S Under-Dash Fuse/Relay Box Connectors A And E
    G08086856Courtesy of AMERICAN HONDA MOTOR CO., INC.
  11. 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 12.
  12. With the connectors still disconnected, 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 13.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    E9 GRN Ignition switch ON (II), or power mode ON Connect terminals A1 and E9: The windshield washer motor should run.
    • Poor ground (G201) or an open in the ground wire
    • Faulty windshield washer motor
    • An open or high resistance in the wire
    A25(1) WHT Under all conditions Connect to ground with a jumper wire: The headlight washer motor should run.
    • Blown No. 2-3 (H/L WASHER) (30 A) fuse in the under-hood fuse/relay box
    • Poor ground (G202) or an open in the ground wire
    • Faulty headlight washer motor
    • Faulty headlight washer motor relay
    • An open or high resistance in the wire
    A4(1) LT BLU Headlight washer switch pushed Check for continuity to ground: There should be continuity.
    • Faulty headlight washer switch
    • Poor ground (G401) or an open in the ground wire
    • An open or high resistance in the wire
    Headlight washer switch released Check for continuity to ground: There should be no continuity.
    • Faulty headlight washer switch
    • A short to ground in the wire
    (1) With headlight washer
  13. Reconnect the connectors to the passenger's under-dash fuse/relay box, 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 14.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A1 PNK Ignition switch ON (II), or power mode ON Measure the voltage to ground: There should be battery voltage.
    • Blown No. 3 (20 A) fuse in the driver's under-dash fuse/relay box
    • Faulty driver's under-dash fuse/relay box
    • An open or high resistance in the wire
    A35 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
    • Faulty driver's under-dash fuse/relay box
    • An open or high resistance in the wire
    E16 BLK In all ignition switch positions or all power modes Measure the voltage to ground: There should be less than 0.2V.
    • Poor ground(G203)
    • An open or high resistance in the ground wire
    E15 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(G203)
    • An open or high resistance in the ground wire
    A36 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(G405)
    • An open or high resistance in the ground wire
    A37 BRN In all ignition switch positions or all power modes Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G402)
    • An open or high resistance in the ground wire
  14. If multiple failures are found on more than one control unit, replace the driver's under-dash fuse/relay box (includes the driver's MICU) (see DRIVER'S UNDER-DASH FUSE/RELAY BOX (MICU) REMOVAL AND INSTALLATION ). If input failures are related to a particular control unit, replace the control unit.
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