2007 Honda Fit Base, AutomaticFACTORY OEM SERVICE PROCEDURE

Security Control Unit Input Test

  1. Remove the driver's dashboard under cover (see DRIVER'S DASHBOARD UNDERCOVER REMOVAL/INSTALLATION ).
  2. Disconnect security control unit connector A (20P) and connector B (16P) from the control unit (C).
    Fig 1: Identifying Security Control Unit Connector A (20P) And Connector B (16P) Terminals
    G05456588Courtesy of AMERICAN HONDA MOTOR CO., INC.
  3. Inspect all 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 connectors still disconnected, make these input tests at the appropriate 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 5.
    SECURITY CONTROL UNIT INPUT

    Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
    B13 BLK/YEL Under all conditions Attach to ground: The security indicator should come on
    • Blown No. 8 (10 A) fuse in the under-hood fuse/relay box
    • Faulty gauge control module
    • An open in the wire
    B9 BRN Under all conditions Check for continuity to ground: There should be continuity.
    • Poor ground (G401)
    • Faulty audio unit
    • An open in the wire
    A6 PNK/BLK Under all conditions Check for continuity between the A6 terminal and gauge control module connector B (14P) No. 4 terminal (connectors disconnected): There should be continuity. An open in the wire
    A17 LT GRN/ BLK Under all conditions Check for continuity between the A17 terminal and gauge control module connector B (14P) No. 5 terminal (connectors disconnected): There should be continuity. An open in the wire
    B2 ORN Under all conditions Attach to ground: Horn should sound
    • Blown No. 16 (15 A) fuse in the under-hood fuse/relay box.
    • Faulty horn relay
    • Faulty horn
    • Faulty under-hood fuse/relay box
    • An open in the wire
    B4 BRN/YEL Under all conditions Attach to ground: Headlights should come on
    • Faulty headlight relay
    • Faulty under-hood fuse/relay box
    • An open in the wire
    B5 BLU Under all conditions Attach to ground: The parking lights and dash lights should come on
    • Blown No. 22 (10 A) fuse in the under-dash fuse/relay box
    • Faulty taillight relay
    • An open in the wire
  5. Reconnect the connectors to the security control unit, and perform these input tests at the appropriate connectors.
    • If any test indicates a problem, find and correct the cause, then recheck the system.
    • If all the input tests prove OK, the security control unit internal circuit must be faulty.
SECURITY CONTROL UNIT INPUT

Cavity Wire Test condition Test: Desired result Possible cause if result is not obtained
B8 WHT/RED Under all conditions Measure the voltage to ground: There should be battery voltage
  • Blown No. 8 (10 A) fuse in the under-hood fuse/relay box
  • An open in the wire
A11 YEL Ignition switch ON (II) Measure the voltage to ground: There should be battery voltage
  • Blown No. 3 (10 A) fuse in the under-dash fuse/relay box
  • An open in the wire
B16 BLK Under all conditions Measure the voltage to ground: There should be less than 0.5 V
  • Poor ground (G403)
  • An open in the wire
A20 GRN Driver's door open Measure the voltage to ground: There should be less than 1 V
  • Faulty driver's door switch
  • An open in the wire
Driver's door closed Measure the voltage to ground: There should be 5 V or more.
  • Faulty driver's door switch
  • A short to ground in the wire
A9 PUR Front passenger's door open (rear doors must be closed) Measure the voltage to ground: There should be less than 1 V
  • Faulty front passenger's door switch
  • An open in the wire
Front passenger's door closed (rear doors must be closed) Measure the voltage to ground: There should be 5 V or more
  • One of the passenger door switches is faulty
  • A short to ground in the wire
Left (right) rear door open (all other doors must be closed) Measure the voltage to ground: There should be less than 1 V
  • Faulty rear door switch
  • An open in the wire
Left (right) rear door closed (all other doors must be closed) Measure the voltage to ground: There should be 5 V or more
  • One of the passenger door switches is faulty
  • A short to ground in the wire
A8 GRN/WHT Ignition key is in the ignition switch Measure the voltage to ground: There should be less than 1 V
  • Faulty key switch
  • Poor ground (G402)
  • An open in the wire
Ignition key switch is out of the ignition switch Measure the voltage to ground: There should be 5 V or more.
  • Faulty key switch
  • A short to ground in the wire
A18 GRN/BLK Hood open Measure the voltage to ground: There should be less than 1 V.
  • Faulty hood switch
  • Poor ground (G301)
  • An open in the wire
Hood closed Measure the voltage to ground: There should be 5 V or more.
  • Faulty hood switch
  • A short to ground in the wire
A7 GRN/RED Tailgate open Measure the voltage to ground: There should be less than 1 V.
  • Faulty tailgate latch switch
  • Poor ground (G501)
  • An open in the wire
Tailgate closed Measure the voltage to ground: There should be 5 V or more.
  • Faulty tailgate latch switch
  • A short to ground in the wire
A1 WHT/BLK Driver's door lock knob unlocked Measure the voltage to ground: There should be less than 1 V.
  • Faulty driver's door lock knob switch
  • Poor ground (G402)
  • An open in the wire
Driver's door lock knob locked Measure the voltage to ground: There should be 5 V or more.
  • Faulty driver's door lock knob switch
  • A short to ground in the wire
A12 YEL/RED Front passenger's door lock knob unlocked Measure the voltage to ground: There should be less than 1 V.
  • Faulty front passenger's door lock knob switch
  • Poor ground (G403)
  • An open in the wire
A2 WHT/BLU Left rear door lock knob unlocked (right rear door and tailgate lock knobs must be in the locked position) Measure the voltage to ground: There should be less than 1 V.
  • Faulty left rear door lock knob switch
  • Poor ground (G501)
  • An open in the wire
Right rear door lock knob unlocked (left rear door and tailgate lock knob must be in the locked position) Measure the voltage to ground: There should be less than 1 V.
  • Faulty tailgate lock knob switch
  • Poor ground (G501)
  • An open in the wire
Tailgate lock knob unlocked (left and right rear door lock knobs must be in the locked position) Measure the voltage to ground: There should be less than 1 V.
  • Faulty tailgate lock knob switch
  • Poor ground (G501)
  • An open in the wire
Left rear door, right rear door, and tailgate lock knobs in the locked position Measure the voltage to ground: There should be 5 V or more.
  • Faulty lock knob switch
  • A short to ground in the wire
A3 WHT Driver's door key cylinder unlocked Measure the voltage to ground: There should be less than 1 V.
  • Faulty driver's door key cylinder switch
  • Poor ground (G402)
  • An open in the wire
Driver's door key cylinder in neutral Measure the voltage to ground: There should be 5 V or more.
  • Faulty driver's door key cylinder switch
  • A short to ground in the wire
A4 WHT/RED Driver's door key cylinder locked Measure the voltage to ground: There should be less than 1 V.
  • Faulty driver's door key cylinder switch
  • Poor ground (G402)
  • An open in the wire
Driver's door key cylinder in neutral Measure the voltage to ground: There should be 5 V or more.
  • Faulty driver's door key cylinder switch
  • A short to ground in the wire
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