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Keyless Access System (Keyless Access Control Unit, Electric Steering Lock, and TPMS Control Unit) Input Test (2014 2015)

Keyless Access/TPMS Control Unit 

1. Turn the vehicle to the OFF (LOCK) mode.

2. Disconnect the keyless access/TPMS control unit connectors

NOTE: All connector views are shown from the wire side of the female terminals.
GHH326492Courtesy of HONDA, U.S.A., INC.

3. Inspect the connectors and socket terminals to be sure they are all making good contact:

4. With the connectors still disconnected, do the following input tests:

Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
C4 LT BLU Under all conditions Check for continuity between terminal C4 and data link connector (DLC) terminal No. 7:There should be continuity. An open or high resistance in the K-LINE wire
Check for continuity between terminal C4 and body ground:There should be no continuity. A short to ground in the K-LINE wire
C6 BLU Under all conditions Check for continuity between terminal C4 and data link connector (DLC) terminal No. 15:There should be continuity. An open or high resistance in the P-LINE wire
Check for continuity between terminal C6 and body ground:There should be no continuity. A short to ground in the P-LINE wire
B10 BLK Press the engine start/stop button Measure the voltage to ground:There should be battery voltage.
  • Blown No. D18 (10 A) fuse in the driver's under-dash fuse/relay box
  • Faulty driver's under-dash fuse/relay box
  • Faulty engine start/stop switch
  • An open or high resistance in the wire
B11 GRY Press the engine start/stop button Check for continuity to ground:There should be continuity.
  • Faulty keyless access/TPMS control unit
  • Faulty engine start/stop switch
  • An open or high resistance in the wire
C5 PUR Jump the SCS line with the HDS, disconnect PCM connector A (51P) Check for continuity between terminal driver's under-dash fuse/relay box connector F (32P) terminal No. 18 and PCM connector A (51P) terminal No. 38:There should be continuity.
  • An open in the S-NET wire
  • PCM
Disconnect the driver's under-dash fuse/relay box connector G (16P) Check for continuity between terminal C5 and driver's under-dash fuse/relay box connector G (16P) terminal No. 12:There should be continuity.
  • An open in the S-NET wire
  • Faulty driver's under-dash fuse/relay box
Check for continuity between terminal C5 and body ground:There should be no continuity. A short to ground in the S-NET wire

5. Reconnect the connectors, and do the following input tests:

Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
A1 RED Under all conditions Measure the voltage to ground:There should be battery voltage.
  • Blown No. D18 (10 A) fuse in the driver's under-dash fuse/relay box
  • Faulty driver's under-dash fuse/relay box
  • An open or high resistance in the wire
B18 GRN Under all conditions Measure the voltage to ground:There should be battery voltage.
  • Blown No. C16 (10 A) fuse in the under-hood fuse/relay box
  • Faulty under-hood fuse/relay box
  • An open or high resistance in the wire
A17 BRN In all power modes Measure the voltage to ground:There should be less than 0.2 V.
  • Poor ground (G501)
  • An open or high resistance in the ground wire
B36 BRN In all power modes Measure the voltage to ground:There should be less than 0.2 V.
  • Poor ground (G501)
  • An open or high resistance in the ground wire
B30 YEL Vehicle ON mode Measure the voltage to ground:There should be battery voltage.
  • Blown No. B3-2 (30 A) fuse in the main under-hood fuse box
  • Faulty under-dash subrelay box
  • An open or high resistance in the wire
B34 YEL Vehicle ON mode Measure the voltage to ground:There should be battery voltage.
  • Blown No. D21 (20 A) fuse in the driver's under-dash fuse/relay box
  • Faulty driver's under-dash fuse/relay box
  • Faulty under-dash subrelay box
  • An open or high resistance in the wire
B29 RED Vehicle ON mode Measure the voltage to ground:There should be battery voltage.
  • Blown No. B3-7 (30 A) fuse in the main under-hood fuse box
  • Faulty under-dash subrelay box
  • An open or high resistance in the wire
B27 LT GRN Vehicle ON mode Measure the voltage to ground:There should be battery voltage.
  • Blown No. B3-2 (30 A) fuse in the main under-hood fuse box
  • Faulty under-dash subrelay box
  • An open or high resistance in the wire
C14 WHT Driver's door outer handle lock button pushed Measure the voltage to ground:There should be less than 0.2 V.
  • Faulty driver's door outer handle
  • Poor ground (G501) or an open in the ground wire
  • An open or high resistance in the wire
Driver's door outer handle lock button released Measure the voltage to ground:There should be about 5 V.
  • Faulty driver's door outer handle
  • A short to ground in the wire
Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
C13 ORN Front passenger's door outer handle lock button pushed Measure the voltage to ground:There should be less than 0.2 V.
  • Faulty front passenger's door outer handle
  • Poor ground (G507) or an open in the ground wire
  • An open or high resistance in the wire
Front passenger's door outer handle lock button released Measure the voltage to ground:There should be about 5 V.
  • Faulty front passenger's door outer handle
  • A short to ground in the wire
C7 WHT Left rear door outer handle lock button pushed Measure the voltage to ground:There should be less than 0.2 V.
  • Faulty left rear door outer handle
  • Poor ground (G602) or an open in the ground wire
  • An open or high resistance in the wire
Left rear door outer handle lock button released Measure the voltage to ground:There should be about 5 V.
  • Faulty left rear door outer handle
  • A short to ground in the wire
C8 LT GRN Right rear door outer handle lock button pushed Measure the voltage to ground:There should be less than 0.2 V.
  • Faulty right rear door outer handle
  • Poor ground (G604) or an open in the ground wire
  • An open or high resistance in the wire
Right rear door outer handle lock button released Measure the voltage to ground:There should be about 5 V.
  • Faulty right rear door outer handle
  • A short to ground in the wire
B1 PNK Parking brake pedal pressed Measure the voltage to ground:There should be less than 0.2 V.
  • Faulty parking brake switch
  • Faulty parking brake switch ground
  • An open or high resistance in the wire
Parking brake pedal released Measure the voltage to ground:There should be about 5 V.
  • Faulty parking brake switch
  • A short to ground in the wire
C16 LT BLU Power tailgate outer handle switch pushed Measure the voltage to ground:There should be less than 0.2 V.
  • Faulty Power tailgate outer handle switch
  • Faulty rearview camera unit
  • Faulty power tailgate control unit
  • An open or high resistance in the wire
Power tailgate outer handle switch released Measure the voltage to ground:There should be about 5 V.
  • Faulty Power tailgate outer handle switch
  • A short to ground in the wire
Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
C10 LT GRN Shift lever in P position Measure the voltage to ground:There should be less than 0.2 V.
  • Faulty transmission range switch
  • Faulty driver's under-dash fuse/relay box
  • Poor ground (G101) or an open in the ground wire
  • An open or high resistance in the wire
Shift lever in any position other than P Measure the voltage to ground:There should be about 5 V.
  • Faulty transmission range switch
  • A short to ground in the wire
C9 LT BLU Shift lever in P position Measure the voltage to ground:There should be about 5 V.
  • Faulty park pin switch
  • A short to ground in the wire
Shift lever in any position other than P Measure the voltage to ground:There should be less than 0.2 V.
  • Faulty park pin switch
  • Poor ground (G506) or an open in the ground wire
  • An open or high resistance in the wire
B19 PUR Brake pedal pressed Measure the voltage to ground:There should be battery voltage.
  • Blown No. B2-6 (30 A) fuse in the main 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
Brake pedal released Measure the voltage to ground:There should be less than 0.2 V. Faulty brake pedal position switch
B3 RED Electric steering lock (LOCK) Measure the voltage to ground:There should be about 5 V.
  • Faulty electric steering lock
  • A short to ground in the wire
Electric steering lock (UNLOCK) Measure the voltage to ground:There should be less than 0.2 V.
  • Faulty electric steering lock
  • An open or high resistance in the wire

Electric Steering Lock 

NOTE:

6. Turn the vehicle to the OFF (LOCK) mode.

7. Disconnect the electric steering lock 12P connector

.

GHH326493Courtesy of HONDA, U.S.A., INC.

8. Inspect the connector and socket terminals to be sure they are all making good contact:

9. Reconnect the connector, and do the following input tests:

Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
3 RED Under all conditions Measure the voltage to ground:There should be battery voltage.
  • Blown No. D18 (10 A) fuse in the driver's under-dash fuse/relay box
  • Faulty driver's under-dash fuse/relay box
  • An open or high resistance in the wire
12 YEL Vehicle ON mode Measure the voltage to ground:There should be battery voltage.
  • Blown No. D23 (7.5 A) fuse in the driver's under-dash fuse/relay box
  • Faulty driver's under-dash fuse/relay box
  • Faulty under-dash subrelay box
  • An open or high resistance in the wire
7 BRN In all power modes Measure the voltage to ground:There should be less than 0.2 V.
  • Poor ground (G501)
  • An open or high resistance in the ground wire
8 RED Electric steering lock (LOCK) Measure the voltage to ground:There should be about 5 V.
  • Faulty keyless access/TPMS control unit
  • A short to ground in the wire
  • An open or high resistance in the wire
Electric steering lock (UNLOCK) Measure the voltage to ground:There should be less than 0.2 V. Faulty electric steering lock
5 PNK Vehicle ON mode Measure the voltage to ground:There should be battery voltage.
  • Faulty keyless access/TPMS control unit
  • An open or high resistance in the wire
  • A short to ground in the wire

10. If multiple failures are found on more than one control unit, replace the keyless access/TPMS control unit .

If input failures are related to a particular control unit, replace the control unit.