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MICU Input Test

  1. Turn the ignition switch to LOCK (0).
  2. Remove the fuse lid panel (see FUSE LID PANEL REMOVAL/INSTALLATION ), and remove the driver's dashboard lower cover (see FUSE LID PANEL REMOVAL/INSTALLATION ).
  3. Disconnect under-dash fuse/relay box connectors A, B, N, Q, R, and Y.
    NOTE: All connector views are wire side of female terminals.
    Fig 1: Identifying Under-Dash Fuse/Relay Box Connectors A, B, N, Q, R, And Y
    G06953871Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. Inspect the connector and socket terminals to make 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, make these input tests at the 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.
    MICU INPUT TEST REFERENCE

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A18 BLU VSA modulator-control unit 32P connector disconnected Check for continuity between terminal A18 and VSA modulator-control unit 32P connector terminal No. 8: There should be continuity. An open or high resistance in the wire
    B16 BLU EPS control unit connector A (11P) disconnected Check for continuity between terminal B16 and EPS control unit connector terminal A5: There should be continuity. An open or high resistance in the wire
    Y7 BLU Under all conditions Check for continuity between terminal Y7 and data link connector (DLC) (16P) connector terminal No. 7; There should be continuity. An open or high resistance in the wire
    Y7 BLU Immobilizer-keyless control unit 7P connector disconnected Check for continuity between terminal Y7 and immobilizer-keyless control unit 7P connector terminal No. 3: There should be continuity. An open or high resistance in the wire
    Y7(1) BLU Audio-navigation unit connector A (24P) disconnected Check for continuity between terminal Y7 and audio-navigation unit connector terminal A13: There should be continuity. An open or high resistance in the wire
    Y7(2) BLU Audio unit connector A (24P) disconnected Check for continuity between terminal Y7 and audio unit connector terminal A13: There should be continuity. An open or high resistance in the wire
    Y7 BLU SRS unit connector A (39P) disconnected Check for continuity between terminal Y7 and SRS unit connector terminal A5: There should be continuity. An open or high resistance in the wire
    Y7(3) BLU TPMS control unit 20P connector disconnected Check for continuity between terminal Y7 and TPMS control unit 20P connector terminal No. 7: There should be continuity. An open or high resistance in the wire
    Y6 GRN Immobilizer-keyless control unit 7P connector disconnected Check for continuity between terminal Y6 and immobilizer-keyless control unit 7P connector terminal No. 4: There should be continuity. An open or high resistance in the B-CAN wire
    Y6 GRN Gauge control module 32P connector disconnected Check for continuity between terminal Y6 and gauge control module 32P connector terminal No. 31: There should be continuity. An open or high resistance in the B-CAN wire
    (1) With navigation
    (2) Without navigation
    (3) With TPMS
    MICU INPUT TEST REFERENCE

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    Y6 GRN Climate control unit 36P connector disconnected Check for continuity between terminal Y6 and climate control unit 36P connector terminal No. 7: There should be continuity. An open or high resistance in the wire
    Y6(1) GRN HandsFreeLink control unit 28P connector disconnected Check for continuity between terminal Y6 and HandsFreeLink control unit 28P connector terminal No. 25: There should be continuity. An open or high resistance in the wire
    A18 BLU Disconnect VSA modulator control unit 47P connector Check for continuity to ground: There should be no continuity. A short to ground in the wire
    B16 BLU Disconnect EPS control unit connector A (11P) Check for continuity to ground: There should be no continuity. A short to ground in the wire
    Y7 BLU Disconnect these connectors:
    • Immobilizer-keyless control unit 7P connector
    • TPMS control unit 20P connector(2)
    • Audio-navigation unit connector A (24P)(3)
    • Audio unit connector A (24P)(4)
    • SRS unit connector A (39P)
    		 Check for continuity to ground: There should be no continuity. A short to ground in the wire
    Y6 GRN Disconnect these connectors:
    • Immobilizer-keyless control unit 7P connector
    • Gauge control module 32P connector
    • Climate control unit 36P connector
    • HandsFreeLink control unit 28P connector(1)
    		 Check for continuity to ground: There should be no continuity. A short to ground in the wire
    (1) With HandsFreeLink system
    (2) With TPMS
    (3) With navigation
    (4) Without navigation
  6. Reconnect the connectors to the under-dash fuse/relay box, and make these input tests at the connector.
    • 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.
    MICU INPUT TEST REFERENCE

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    R2 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground(G501)
    • An open or high resistance in the wire
    N5 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground(G502)
    • An open or high resistance in the wire
    Y16 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground(G501)
    • An open or high resistance in the wire
    Q2 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground(G502)
    • An open or high resistance in the wire
    R3 PNK Under all conditions Measure the voltage to ground: There should be battery voltage.
    • Blown No. B1 (15 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the wire
    Q34 PUR Ignition switch ACCESSORY (I) Measure the voltage to ground: There should be battery voltage.
    • Blown No. B14 (7.5 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the wire
    N7 BRN Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
    • Blown No. B20 (15 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the wire
    Y1 LT BLU Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
    • Blown No. B22 (7.5 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the wire
    Y11 RED Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
    • Blown No. B10 (7.5 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the wire
  7. If multiple failures are found on more than one control unit, replace the under-dash fuse/relay box (includes the MICU).

    If input failures are related to a particular control unit, replace the control unit.

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