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Control Unit 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 ).
  1. Remove the driver's dashboard undercover (see DRIVER'S DASHBOARD UNDERCOVER REMOVAL/INSTALLATION ), and the driver's dashboard lower cover (see DRIVER'S DASHBOARD LOWER COVER REMOVAL/INSTALLATION ).
  2. Disconnect the 40P connector (A) from the adaptive front lighting control unit (B).
    Fig 1: Identifying Adaptive Front Lighting Control Unit 40P Connector
    G05496960Courtesy 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. With the connector still disconnected, 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 5.
    WIRE CAVITY REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    17 BLU Under all conditions
    NOTE: Disconnect the steering angle sensor 5P connector.
    		 Check for continuity between the No. 17 terminal and steering angle sensor 5P connector No. 3 terminal:
    There should be continuity.    		 An open in the wire
    18 GRN Under all conditions
    NOTE: Disconnect the steering angle sensor 5P connector.
    		 Check for continuity between the No. 18 terminal and steering angle sensor 5P connector No. 2 terminal:
    There should be continuity.    		 An open in the wire
    38 BRN Under all conditions
    NOTE: Disconnect the steering angle sensor 5P connector.
    		 Check for continuity between the No. 38 terminal and steering angle sensor 5P connector No. 4 terminal:
    There should be continuity.    		 An open in the wire
    20 YEL Under all conditions
    NOTE: Disconnect the VSA modulator-control unit 47P connector.
    		 Check for continuity between the No. 20 terminal and VSA modulator-control unit 47P connector No. 41 terminal:
    There should be continuity.    		 An open in the wire
    40 GRN Under all conditions
    NOTE: Disconnect the VSA modulator-control unit 47P connector.
    		 Check for continuity between the No. 40 terminal and VSA modulator-control unit 47P connector No. 9 terminal:
    There should be continuity.    		 An open in the wire
    23 LT BLU Under all conditions Measure resistance between the No. 37 and No. 23 terminals:
    There should be about 3.5-6.5 Ω.
    • Faulty suspension stroke sensor
    • An open in the wire
    37 GRY
    14 PUR Under all conditions Measure resistance between the No. Hand No. 23 terminals:
    There should be about 0.5-4.5 Ω.
    • Faulty suspension stroke sensor
    • An open in the wire
    23 LT BLU
    16 PUR Under all conditions Measure resistance between the No. 16 and No. 23 terminals:
    There should be about 0.5-4.5 Ω.
    • Faulty suspension stroke sensor
    • An open in the wire
    23 LT BLU
    6 YEL Under all conditions Measure resistance between the No. 6 and No. 8 terminals:
    There should be about 7.8-9.4 Ω.
    • Faulty right adaptive front lighting gearbox
    • An open in the wire
    8 BRN
    7 WHT Under all conditions Measure resistance between the No. 7 and No. 9 terminals:
    There should be about 7.8-9.4 Ω.
    • Faulty left adaptive front lighting gearbox
    • An open in the wire
    9 BLU
    26 BLU Under all conditions Measure resistance between the No. 26 and No. 28 terminals:
    There should be about 7.8-9.4 Ω.
    • Faulty right adaptive front lighting gearbox
    • An open in the wire
    28 GRN
    27 RED Under all conditions Measure resistance between the No. 27 and No. 29 terminals:
    There should be about 7.8-9.4 Ω.
    • Faulty left adaptive front lighting gearbox
    • An open in the wire
    29 YEL
  5. Reconnect the 40P connector to the adaptive front lighting control unit, 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, the control unit must be faulty; replace it.
    WIRE CAVITY REFERENCE CHART

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    24 BLK Under all conditions Measure the voltage to ground:
    There should be less than 0.5 V.
    • Poor ground (G401)
    • An open in the wire
    25
    21 GRN Ignition switch ON (II) Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 11 (7.5 A) fuse in the driver's under-dash fuse/relay box
    • An open in the wire
    22 BLU Ignition switch ON (II) Measure the voltage to ground:
    There should be battery voltage.
    • Blown No. 29 (7.5 A) fuse in the driver's under-dash fuse/relay box
    • An open in the wire
    1 YEL Ignition switch ON (II) and headlight switch ON Measure the voltage between the No. 1 (+) and No. 30 (-) terminals:
    There should be battery voltage.
    • Faulty headlight leveling motor
    • An open in the wire
    30 RED
    36 PNK Ignition switch ON (II) and headlight switch ON Measure the voltage between the No. 36 (+) and No. 30 (-) terminals:
    There should be about 2-12 V (voltage should vary depending on leveling motor position).
    • Faulty headlight leveling motor
    • An open in the wire
    30 RED
    13 GRN Ignition switch ON (II) and headlight switch ON Measure the voltage between the No. 13 (+) and No. 31 (-) terminals:
    There should be about 0.5-4.5 V.
    • Faulty left adaptive front lighting gearbox
    • An open in the wire
    31 PNK
    33 WHT Ignition switch ON (II) and headlight switch ON Measure the voltage between the No. 33 (+) and No. 31 (-) terminals:
    There should be about 0.5-4.5 V.
    • Faulty right adaptive front lighting gearbox
    • An open in the wire
    31 PNK
    32 BLU Ignition switch ON (II) and headlight switch ON Measure the voltage between the No. 32 (+) and No. 31 (-) terminals:
    There should be about 4.5-5.5 V.
    • Faulty adaptive front lighting gearbox
    • An open in the wire
    31 PNK
    3 PUR AFS OFF switch pushed Measure the voltage to ground:
    There should be less than 1 V.
    • Poor ground (G501)
    • Faulty AFS OFF switch
    • An open in the wire
    AFS OFF switch released Measure the voltage to ground:
    There should be 5 V or more.
    • Faulty AFS OFF switch
    • A short to ground in the wire
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