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Driver's Multiplex Control Unit

  1. Remove fuse/relay box located under instrument panel. Turn ignition switch to OFF position. Disconnect driver's multiplex control unit from instrument panel fuse/relay box. See Fig 1 . Disconnect multiplex control unit Gray 16-pin and Gray 26-pin connectors. Ensure terminals of connectors are okay and making proper contact. Repair connector terminals as necessary and retest system. If connector terminals are okay without reconnecting control unit connectors, go to next step.
  2. Using a voltmeter, probe between fuse/relay box 14-pin connector terminal A8 and ground. See Fig 1 . See procedures under DRIVER'S MULTIPLEX CONTROL UNIT CONNECTOR TERMINAL IDENTIFICATION table. If voltage is less than one volt, go to next step. If voltage is one volt or more, check for an open in Black wire or a poor ground. See WIRING DIAGRAMS  . Repair as necessary and retest system.
  3. Using a voltmeter, probe between fuse/relay box 14-pin connector terminal A13 and ground. Turn ignition switch to ON position and measure voltage. If battery voltage exists, go to next step. If battery voltage does not exist, check fuse No. 13 (7.5-amp), located in fuse/relay box under instrument panel. See Figure . If fuse is okay, check for an open in fuse/relay box circuit between fuse No. 13 and terminal A13. See WIRING DIAGRAMS  . Repair as necessary and retest system.
  4. Turn ignition switch to OFF position. Using a fused jumper wire, ground multiplex control unit Gray 26-pin connector terminal B4 (Red/Green wire). If taillights illuminate, go to next step. If taillights do not illuminate, check taillight relay and/or for a faulty circuit in taillight system. See WIRING DIAGRAMS  . Repair as necessary and retest system.
  5. Turn ignition switch to ON position. Using a fused jumper wire, ground multiplex control unit Gray 26-pin connector terminal B7 (White wire). If security indicator light illuminates, go to next step. If security indicator light does not illuminate, check fuse No. 56 (7.5-amp), located in fuse/relay box under instrument panel. If fuse is okay, check indicator light bulb and/or for an open in circuit. See WIRING DIAGRAMS  . Repair as necessary and retest system.
  6. Turn ignition switch to OFF position. Using a fused jumper wire, ground multiplex control unit Gray 26-pin connector terminal B8 (Orange wire). If horns sound, go to next step. If horns do not sound, check fuse No. 56 (7.5-amp), located in fuse/relay box under instrument panel. If fuse is okay, check horn relay, horns, ground connection or for an open circuit. See WIRING DIAGRAMS  . Repair as necessary and retest system.
  7. Ensure ignition switch is in OFF position. Using a fused jumper wire, ground multiplex control unit Gray 26-pin connector terminal B16 (Blue/Red wire). If headlights illuminate, go to next step. If headlights do not illuminate, check headlight relay and/or for a faulty circuit in headlight system. See WIRING DIAGRAMS  . Repair as necessary and retest system.
  8. Reconnect driver's multiplex control unit Gray 16-pin and Gray 26-pin connectors. Using a voltmeter, backprobe between 16-pin connector terminal C7 (Gray wire) and ground. Lock and unlock left rear door lock knob and measure voltage. In UNLOCK position, voltage should be 5 volts or more. In LOCK position, voltage should be less than one volt. If voltage is as specified, go to next step. If voltage is not as specified, check left rear door lock actuator. See DOOR LOCKS - POWER & TRUNK RELEASE article in the ACCESSORIES/SAFETY EQUIPMENT section. If actuator is okay, check ground connections or for an open circuit. See WIRING DIAGRAMS  . Repair as necessary and retest system.
  9. Using a voltmeter, backprobe between 16-pin connector terminal C8 (Green/Orange wire) and ground. Lock and unlock trunk key cylinder switch and measure voltage. In LOCK position, voltage should be 5 volts or more. In UNLOCK position, voltage should be less than one volt. If voltage is as specified, go to next step. If voltage is not as specified, check trunk key cylinder switch. See TRUNK KEY CYLINDER SWITCH TEST under COMPONENT TESTS  . If trunk key cylinder switch is okay, check ground connections or for an open circuit. See WIRING DIAGRAMS  . Repair as necessary and retest system.
  10. Using a voltmeter, backprobe between 16-pin connector terminal C9 (Blue/White wire) and ground. Insert and remove ignition key into and out of ignition switch and measure voltage. With key inserted into ignition switch, voltage should be 5 volts or more. With key removed from ignition switch, voltage should be less than one volt. If voltage is as specified, go to next step. If voltage is not as specified, check ignition key switch. See IGNITION KEY SWITCH TEST under COMPONENT TESTS  . If ignition key switch is okay, check ground connections or for an open circuit. See WIRING DIAGRAMS  . Repair as necessary and retest system.
  11. Using a voltmeter, backprobe between 16-pin connector terminal C15 (Green/Yellow wire) and ground. Open and close left rear door and measure voltage. With door closed, voltage should be 5 volts or more. With door open, voltage should be less than one volt. If voltage is as specified, replace driver's multiplex control unit. If voltage is not as specified, check left rear door switch. See DOOR LOCKS - POWER & TRUNK RELEASE article in the ACCESSORIES/SAFETY EQUIPMENT section. If door switch is okay, check ground connections or for an open in Green/Yellow wire. See WIRING DIAGRAMS  . Repair as necessary and retest system.
Fig 1: Locating Driver's Multiplex Control Unit Connector Terminals
G96A06120Courtesy of AMERICA HONDA MOTOR CO., INC.
DRIVER'S MULTIPLEX CONTROL UNIT CONNECTOR TERMINAL IDENTIFICATION

Terminal (Wire Color) (1) Circuit
14-Pin Connector (2)
A2 Wiper Park Position Input
A4 Vehicle Speed Sensor (VSS) Input
A7 Battery Input
A8 Ground
A10 Multiplex Control Inspection Connector Input
A11 Power Window Relay Control
A13 Ignition Input
Gray 26-Pin Connector
B2 (BLK/RED) Key Interlock Switch Input
B4 (RED/GRN) Lights-On Input/Taillight Relay Control
B5 (GRN) Intermittent ON Input
B6 (GRN/YEL) Intermittent Dwell Timer Input
B7 (WHT) Security Indicator Light Control
B8 (ORG) Horn Control
B9 (BRN/WHT) D-A Line
B10 (PNK/BLU) Wake-Up
B12 (GRN/WHT) Brake Switch Input
B13 (WHT/RED) Key Interlock Solenoid Control
B15 (PNK) Keyless Buzzer Control
B16 (BLU/RED) Headlight Relay Control
B18 (GRN/RED) Intermittent Wiper Control
B19 (GRN/WHT) Intermittent Dwell Timer Input
B20 (BLK/WHT) Wiper ON Input
B22 (RED/YEL) A-D Line
B23 (BRN/YEL) Door D-Line
B25 (WHT/BLK) Ignition Key Light Control
B26 (WHT/GRN) Shift Lock Circuit Input
Gray 16-Pin Connector
C2 (BLK/BLU) Park Position Switch
C3 (LT GRN) Instrument Cluster Illumination Brightness Control
C5 (WHT/BLK) Parking Pin Switch Input
C6 (YEL/GRN) Left Rear Power Window Control
C7 (GRY) Left Rear Lock Knob Switch Input
C8 (GRN/ORG) Trunk Key Cylinder Switch Input
C9 (BLU/WHT) Ignition Key Switch Input
C10 (GRN) Shift Lock Solenoid Control
C11 (BLU/BLK) Instrument Cluster Illumination Brightness Controller
C13 (RED/BLU) Driver's Seat Belt Switch Input
C14 (YEL) Left Rear Power Window Control
C15 (GRN/YEL) Left Rear Door Switch Input
C16 (GRN/WHT) (3) Parking Brake Switch Input
C16 (GRN/RED) (4) Parking Brake Switch Input
(1) Terminals not listed are not used.
(2) Driver's 14-pin multiplex control unit connector connects control unit directly to fuse/relay box located under instrument panel.
(3) Canada only.
(4) USA only.
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