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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 Lighting Control Unit 40P Connector
    G06162820Courtesy 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, do 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.
    TEST RESULT REFERENCE TABLE

    Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
    23 LT BLU Under all conditions Measure resistance between terminals No. 37 and No. 23:
    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 terminals No. 14 and No. 23: 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 terminals No. 16 and No. 23:
    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 terminals No. 6 and No. 8:
    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 terminals No. 7 and No. 9:
    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 terminals No. 26 and No. 28: 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 terminals No. 27 and No. 29:
    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 do 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.
TEST RESULT REFERENCE TABLE

Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
24 BLK Ignition switch ON (II) Measure the voltage to ground: There should be less than 0.1 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 (15 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 terminals No. 1 (+) and No. 30 (-): 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 terminals No. 36 (+) and No. 30 (-): 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 terminals No. 13 (+) and No. 31 (-): 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 terminals No. 33 (+) and No. 31 (-): 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 terminals No. 32 (+) and No. 31 (-):
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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