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MICU Input Test

WARNING: This page is about a different car, the 2011 Acura TL, 2010 Acura TL, and 2009 Acura TL. However, it is still accessible from the selected car via links, so may be relevant.
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, N, P, Q, and R
    NOTE: All connector views are wire side of female terminals
    Fig 1: Driver's MICU Connectors Terminals Chart
    G05988860Courtesy 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 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
    TEST CONDITION CAVITY CHART

    Cavity Wire Test condition Test Desired result Possible cause if desired result is not obtained
    P5(1) BLU Immobilizer-keyless control unit 7P connector disconnected Check for continuity between terminal P5 and immobilizer-keyless control unit 7P connector terminal No 3 There should be continuity An open in the B-CAN wire
    P6(1) PNK Check for continuity between terminal P6 and immobilizer-keyless control unit 7P connector terminal No 4 There should be continuity An open in the B-CAN wire
    P5(2) BLU Power control unit A (36P) connector disconnected Check for continuity between terminal P5 and power control unit connector A (36P) terminal No 17 There should be continuity An open in the B-CAN wire
    P6(2) PNK Check for continuity between terminal P6 and power control unit connector A (36P) terminal No 16 There should be continuity An open in the B-CAN wire
    P5(2) BLU Keyless access control unit B (32P) connector disconnected Check for continuity between terminal P5 and keyless access control unit connector B (32P) terminal No 7 There should be continuity An open in the B-CAN wire
    P6(2) PNK Check for continuity between terminal P6 and keyless access control unit connector B (32P) terminal No 8 There should be continuity An open in the B-CAN wire
    P5(2) BLU Remote slot control unit 40P connector disconnected Check for continuity between terminal P5 and remote slot control unit 40P connector terminal No 23 There should be continuity An open in the B-CAN wire
    P6(2) PNK Check for continuity between terminal P6 and remote slot control unit 40P connector terminal No 3 There should be continuity An open in the B-CAN wire
    P5 BLU Gauge control module 32P connector disconnected Check for continuity between terminal P5 and gauge control module 32P connector terminal No. 25 There should be continuity An open in the B-CAN wire
    P6 PNK Check for continuity between terminal P5 and gauge control module 32P connector terminal No. 26 There should be continuity An open in the B-CAN wire
    P5 BLU Door multiplex control unit 37P connector disconnected Check for continuity between terminal P5 and door multiplex control unit 37P connector terminal No. 33 There should be continuity An open in the B-CAN wire
    P6 PNK Check for continuity between terminal P6 and door multiplex control unit 37P connector terminal No. 35 There should be continuity An open in the B-CAN wire
    (1) Without keyless access system
    (2) With keyless access system
    TEST CONDITION CAVITY CHART

    Cavity Wire Test condition Test Desired result Possible cause if desired result is not obtained
    P5 BLU Passenger's under-dash Fuse/relay box connector A(38P) disconnected Check for continuity between terminal P5 and passenger's under-dash fuse/relay box connector A (38P) terminal No 29 There should be continuity An open in the B-CAN wire
    P6 PNK Check for continuity between terminal P6 and passenger's under-dash fuse/relay box connector A (38P) terminal No 11 There should be continuity An open in the B-CAN wire
    P5 BLU Climate control unit connector C (20P) disconnected Check for continuity between terminal P5 and climate control unit connector B(12P) terminal No 2 There should be continuity An open in the B-CAN wire
    P6 PNK Check for continuity between terminal P6 and climate control unit connector B (12P) terminal No 1 There should be continuity An open in the B-CAN wire
    P5(1) BLU Audio-navigation unit connector D (20P) disconnected Check for continuity between terminal P5 and audio-navigation unit connector D (20P) terminal No 15 There should be continuity An open in the B-CAN wire
    P6(1) PNK Check for continuity between terminal P6 and audio-navigation unit connector D (20P) terminal No 6 There should be continuity An open in the B-CAN wire
    P5(2) BLU Audio unit connector D (20P) disconnected Check for continuity between terminal P5 and audio unit connector D (20P) terminal No 8 There should be continuity An open in the B-CAN wire
    P6(2) PNK Check for continuity between terminal P6 and audio unit connector D (20P) terminal No 18 There should be continuity An open in the B-CAN wire
    P5 BLU Power seat control unit connector A (40P) disconnected Check for continuity between terminal P5 and power seat control unit connector A (40P) terminal No 39 There should be continuity An open in the B-CAN wire
    P6 PNK Check for continuity between terminal P6 and power seat control unit connector A (40P) terminal No 40 There should be continuity An open in the B-CAN wire
    P5 BLU HandsFreeLink control unit 28P connector disconnected Check for continuity between terminal P5 and HandsFreeLink control unit 28P connector terminal No 17 There should be continuity An open in the B-CAN wire
    P6 PNK Check for continuity between terminal P6 and HandsFreeLink control unit 28P connector terminal No 18 There should be continuity An open in the B-CAN wire
    P5(3) BLU AcuraLink control unit connector A (32P) disconnected Check for continuity between terminal P5 and AcuraLink control unit connector A (32P) terminal No 8 There should be continuity An open in the B-CAN wire
    P6(3) PNK Check for continuity between terminal P6 and AcuraLink control unit connector A (32P) terminal No 9 There should be continuity An open in the B-CAN wire
    Q16 LT BLU Under all conditions Check for continuity between terminal Q16 and data link connector 16P connector terminal No 7 There should be continuity An open in the B-CAN wire
    (1) With navigation system
    (2) Without navigation system
    (3) With AcuraLink
  6. Reconnect the connectors to the driver's 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
    NOTE: These are power and ground tests for the driver's MICU
    TEST CONDITION CAVITY CHART

    Cavity Wire Test condition Test Desired result Possible cause if desired result is not obtained
    F11 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 resistantce in the wire
    P9 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
    • Faulty driver's under-dash fuse/relay box
    • An open or high resistance in the wire
    P20 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
    N12 BLK In all ignition switch positions or all power modes Measure the voltage to ground There should be less than 0.2V
    • Poor ground (G402)
    • An open or high resistance in the ground wire
    Q1 BLK In all ignition switch positions or all power modes Measure the voltage to ground There should be less than 0.2V
    • Poor ground (G402)
    • An open or high resistance in the ground wire
    Q2 BRN In all ignition switch positions or all power modes Measure the voltage to ground There should be less than 0.2V
    • Poor ground (G401)
    • An open or high resistance in the ground wire
    R2 BRN In all ignition switch positions or all power modes Measure the voltage to ground There should be less than 0.2V
    • Poor ground (G401)
    • An open or high resistance in the ground wire
    R5 BLK In all ignition switch positions or all power modes Measure the voltage to ground There should be less than 0.2V
    • Poor ground (G402)
    • An open or high resistance in the ground wire

    Passenger's MICU 

  7. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode, and remove the passenger's kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS )
  8. Disconnect passenger's under-dash fuse/relay box connectors A and E
    NOTE: All connector views are wire side of female terminals
    Fig 2: Passenger's MICU Connectors Terminals Chart
    G05988861Courtesy of AMERICAN HONDA MOTOR CO., INC.
  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 connectors to the passenger's under-dash fuse/relay box, turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode, 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 11
    TEST CONDITION CAVITY CHART

    Cavity Wire Test condition Test Desired result Possible cause if desired result is not obtained
    A14 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
    • Faulty driver's under-dash fuse/relay box
    • An open in the wire between terminals A14 and P9 in the driver's under-hood fuse/relay box
    A35 BRN Ignition switch ON (II), or ignition 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 in the wire between terminals A14 and P20 in the driver's under-hood fuse/relay box
    A36 BLK In all ignition switch positions or all power modes Measure the voltage to ground There should be less than 0 2V
    • Poor ground (G405)
    • An open or high resistance in the ground wire
    A37 GRY In all ignition switch positions or all power modes Measure the voltage to ground There should be less than 0 2V
    • Poor ground (G401)
    • 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 2V
    • Poor ground (G201)
    • An open or high resistance in the ground 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
  11. 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/INSTALLATION ) If input failures are related to a particular control unit, replace the control unit
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