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Control Unit Input Test

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

Under-dash Fuse/Relay Box 

  1. Turn the ignition switch to LOCK (0) and remove the left kick panel (see TRIM REMOVAL/INSTALLATION - DOOR AREAS ).
  2. Disconnect under-dash fuse/relay box connectors E, F, H, P, Q, and W.
    NOTE: All connector views are wire side of female terminals.
    Fig 1: Identifying Under-Dash Fuse/Relay Box Connector E (16P) Terminals
    G08055376Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 2: Identifying Under-Dash Fuse/Relay Box Connector P (30P) Terminals
    G08055377Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 3: Identifying Under-Dash Fuse/Relay Box Connector F (14P) Terminals
    G08055378Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 4: Identifying Under-Dash Fuse/Relay Box Connector Q (14P) Terminals
    G08055379Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 5: Identifying Under-Dash Fuse/Relay Box Connector H (14P) Terminals
    G08055380Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 6: Identifying Under-Dash Fuse/Relay Box Connector W (5P) Terminals
    G08055381Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. 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 4.
  4. Reconnect the connectors, turn the ignition switch to ON (II), 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 5.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    E9 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G601) or an open in the ground wire
    • An open or high resistance in the wire
    H9
    Q4
    P1 BRN In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G502) or an open in the ground wire
    • An open or high resistance in the wire
    P13 PNK Ignition key inserted into the ignition switch Measure the voltage to ground: There should be less than 0.2 V.
    • Faulty ignition key switch
    • Faulty under-dash fuse/relay box
    • Poor ground (G601) or an open in the ground wire
    • An open or high resistance in the wire
    Ignition switch LOCK (0) and the ignition key removed from the ignition switch Measure the voltage to ground: There should be at least 5 V.
    • Faulty ignition key switch
    • A short to ground in the wire
    E15 GRN Driver's door open Measure the voltage to ground: There should be less than 0.2 V.
    • Faulty driver's door switch
    • Faulty driver's door switch ground
    • An open or high resistance in the wire
    Driver's door closed Measure the voltage to ground: There should be at least 5 V.
    • Faulty driver's door switch
    • A short to ground in the wire
    H12 LT GRN Front passenger's door open Measure the voltage to ground: There should be less than 0.2 V.
    • Faulty front passenger's door switch
    • Faulty front passenger's door switch ground
    • An open or high resistance in the wire
    Front passenger's door closed Measure the voltage to ground: There should be at least 5 V.
    • Faulty front passenger's door switch
    • A short to ground in the wire
    Q2 GRY Right rear door open Measure the voltage to ground: There should be less than 0.2 V.
    • Faulty right rear door switch
    • Faulty right rear door switch ground
    • An open or high resistance in the wire
    Right rear door closed Measure the voltage to ground: There should be at least 5 V.
    • Faulty right rear door switch
    • A short to ground in the wire
    Q8 GRN Left rear door open Measure the voltage to ground: There should be less than 0.2 V.
    • Faulty left rear door switch
    • Faulty left rear door switch ground
    • An open or high resistance in the wire
    Left rear door closed Measure the voltage to ground: There should be at least 5 V.
    • Faulty left rear door switch
    • A short to ground in the wire
    F14 ORN Under all conditions Attach to ground: The ignition key light should come on.
    • Blown No. 4 (40 A) fuse in the main under-hood fuse box
    • Blown No. 6 (7.5 A) fuse in the under-dash fuse/relay box
    • Faulty main under-hood fuse box
    • Faulty under-dash fuse/relay box
    • Faulty ignition key light
    • An open or high resistance in the wire
    W4 LT GRN Under all conditions (Interior light control button (DOOR) pressed) Attach to ground: The individual map lights and footwell lights should come on.
    • Blown No. 4 (40 A) fuse in the main under-hood fuse box
    • Blown No. 6 (7.5 A) fuse in the under-dash fuse/relay box
    • Faulty main under-hood fuse box
    • Faulty under-dash fuse/relay box
    • Faulty roof console
    • Faulty rear individual map lights
    • Blown footwell light bulbs
    • An open or high resistance in the wire

    Rear Fuse/Relay Box 

  5. Turn the ignition switch to LOCK (0).
  6. Remove the left rear side trim (see TRIM REMOVAL/INSTALLATION - REAR SIDE AREA ).
  7. Disconnect rear fuse/relay box connector B (34P).
    Fig 7: Identifying Rear Fuse/Relay Box Connector B (34P)
    G08055382Courtesy of AMERICAN HONDA MOTOR CO., INC.
  8. 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 9.
  9. Reconnect the connectors, then turn the ignition switch to ON (II), 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 10.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    B18 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground (G603, G604) or an open in the ground wire
    • An open or high resistance in the wire
    B29
    B4 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
    • Blown No. 4 (40 A) fuse in the main under-hood fuse box
    • Faulty main under-hood fuse box
    • Blown No. 7 (10 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the wire
    B23 LT BLU Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
    • Blown No. 21 (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

    Driver's MPCS Unit 

  10. Turn the ignition switch to LOCK (0).
  11. Remove the driver's door panel (see FRONT DOOR PANEL REMOVAL/INSTALLATION ).
  12. Disconnect driver's MPCS unit connectors A (40P) and B (14P).
    Fig 8: Identifying Driver's MPCS Unit Connectors A (40P) Terminals
    G08055383Courtesy of AMERICAN HONDA MOTOR CO., INC.
    Fig 9: Identifying Driver's MPCS Unit Connectors B (14P) Terminals
    G08055384Courtesy of AMERICAN HONDA MOTOR CO., INC.
  13. 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 14.
  14. 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 15.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A23.A27 PNK.BRN Driver's door lock switch in LOCK Check for continuity: There should be continuity.
    • Faulty driver's door lock switch
    • An open or high resistance in the wire
    Driver's door lock switch in neutral or UNLOCK Check for continuity: There should be no continuity.
    • Faulty driver's door lock switch
    • A short to ground in the wire
    A24.A27 RED.BRN Driver's door lock switch in UNLOCK Check for continuity: There should be continuity.
    • Faulty driver's door lock switch
    • An open in the wire
    Driver's door lock switch in neutral or LOCK Check for continuity: There should be no continuity.
    • Faulty driver's door lock switch
    • A short to ground in the wire
  15. Reconnect the connectors, 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 16.
    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    A5 BLK In all ignition switch positions Measure the voltage to ground: There should be less than 0.2 V.
    • Poor ground(G601) or an open in the ground wire
    • An open or high resistance in the wire
    B14
    A7 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
    • Blown No. 4 (40 A) fuse in the main under-hood fuse box
    • Faulty main under-hood fuse box
    • Blown No. 7 (10 A) fuse in the under-dash fuse/relay box
    • Faulty under-dash fuse/relay box
    • An open or high resistance in the wire
    A25 YEL Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage.
    • Blown No. 21 (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
  16. If multiple failures are found on more than one control unit, replace the under-dash fuse/relay box (includes the MICU) (see REMOVAL AND INSTALLATION ). If input failures are related to a particular control unit, replace the control unit.