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Power Control Unit

  1. 7. Press the engine start/stop button to select the OFF mode.
  2. 8. Remove the driver's dashboard undercover (see DRIVER'S DASHBOARD UNDERCOVER REMOVAL/INSTALLATION ).
  3. 9. Disconnect the connectors (A) from the power control unit (B).
    NOTE: All connector views are wire side of female terminals.
    Fig 1: Identifying Power Control Unit Connectors Terminals
    G06680438Courtesy of AMERICAN HONDA MOTOR CO., INC.
  4. 10. Inspect the connector and the 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 11.
  5. 11. With the connectors still disconnected, do these input tests at the following 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 12.
      CONTROL UNIT INPUT TEST REFERENCE

      Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
      C3 GRY Under all conditions Check for continuity between terminal C3 and data link connector (DLC) terminal No. 1: There should be continuity. An open in the DIAG-H wire
      Check for continuity between terminal C3 and body ground: There should be no continuity. A short to ground in the wire
  6. 12. Reconnect the connectors to the power control unit, and do these input tests at the following 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 13.
      CONTROL UNIT INPUT TEST REFERENCE

      Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
      A1 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
      • Blown No. 3-1 (IG MAIN) (50 A) fuse in the under-hood fuse/relay box
      • An open or high resistance in the wire
      C1 WHT Under all conditions Measure the voltage to ground: There should be battery voltage.
      • Blown No. 15 (10 A) fuse in the under-hood fuse/relay box
      • An open or high resistance in the wire
      C20 RED Under all conditions Measure the voltage to ground: There should be battery voltage.
      • Blown No. 12 (10 A) fuse in the passenger's under-dash fuse/relay box
      • An open or high resistance in the wire
      C18 BLK In all power modes Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G402) or an open in the ground wire
      • An open or high resistance in the wire
      C36 BLK In all power modes Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G402) or an open in the ground wire
      • An open or high resistance in the wire
      C11 BRN Power mode ACC Measure the voltage to ground: There should be battery voltage.
      • Faulty power control unit
      • Faulty driver's under-dash fuse/relay box
      • A short to ground in the wire
      C10 LT GRN Power mode START Measure the voltage to ground: There should be battery voltage.
      • Faulty ECM/PCM
      • Faulty power control unit
      • A short to ground in the wire
      C4 BRN Under all conditions Connect to ground with a jumper wire:
      The engine start/stop switch light should come on.
      • Blown No. 12 (10 A) fuse in the passenger's under-dash fuse/relay box
      • Faulty engine start/stop switch
      • An open or high resistance in the wire
      C5 PNK Under all conditions Connect to ground with a jumper wire: The engine start/stop switch indicator should come on.
      • Blown No. 12 (10 A) fuse in the passenger's under-dash fuse/relay box
      • Faulty engine start/stop switch
      • An open or high resistance in the wire
      C13 PUR Power mode ON Measure the voltage to ground: There should be battery voltage.
      • Power control unit
      • A short to ground in the wire
      C14 RED Under all conditions Measure the voltage to ground: There should be battery voltage.
      • Faulty driver's MICU
      • An open or high resistance in the wire
      • A short to ground in the wire
      C19 LT GRN Brake pedal pressed Measure the voltage to ground: There should be battery voltage.
      • Blown No. 10 (20 A) fuse in the under-hood fuse/relay box
      • Faulty brake pedal position switch
      • An open or high resistance in the wire
      • A short to ground in the wire
      C22 LT GRN Power mode ON, parking brake lever pulled Measure the voltage to ground: There should be less than 0.2 V.
      • Faulty parking brake switch
      • An open or high resistance in the wire
      Power mode ON, parking brake lever released Measure the voltage to ground: There should be about 5 V.
      • Faulty parking brake switch
      • A short to ground in the wire
      C23 GRY Keyless access system mode switch OFF Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G501) or an open in the ground wire
      • Faulty keyless access system mode switch
      • An open or high resistance in the wire
      Keyless access system mode switch ON Measure the voltage to ground: There should be battery voltage.
      • Faulty keyless access system mode switch
      • A short to ground in the wire
      C24 PUR Shift lever out of P position Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G403) or an open in the ground wire
      • Faulty park pin switch
      • An open or high resistance in the wire
      Shift lever in P position Measure the voltage to ground: There should be battery voltage.
      • Faulty park pin switch
      • A short to ground in the wire
      C25 RED Shift lever in P position Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G101) or an open in the ground wire
      • Faulty transmission range switch
      • An open or high resistance in the wire
      Shift lever out of P position Measure the voltage to ground: There should be battery voltage.
      • Faulty transmission range switch
      • A short to ground in the wire
      C26 YEL Insert the remote into the remote slot Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G403) or an open in the ground wire
      • Faulty remote slot
      • An open or high resistance in the wire
      C27 PNK Insert the remote into the remote slot Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G403) or an open in the ground wire
      • Faulty remote slot
      • An open or high resistance in the wire
      C28 (M/T) PNK Power mode ON, clutch pedal pressed. Measure the voltage to ground: There should be less than 0.2 V.
      • Poor ground (G301) or an open in the ground wire
      • Faulty clutch pedal position switch A
      • An open or high resistance in the wire
      Power mode ON, clutch pedal released. Measure the voltage to ground: There should be battery voltage.
      • Faulty clutch pedal position switch A
      • A short to ground in the wire
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