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Immobilizer-Keyless Control Unit Input Test

NOTE: 

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

2. Disconnect the immobilizer-keyless control unit 7P connector.

GHH83136Courtesy of HONDA, U.S.A., INC.

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

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

Cavity Wire Terminal name Test condition Test: Desired result Possible cause if desired result is not obtained
2 BLU S-NET Jump the SCS line with the HDS, disconnect PCM connector A (51P) Measure the voltage to ground: There should be about 5 V.
  • An open or high resistance in the wire
  • A short to ground in the wire
Check for continuity between the terminal and PCM connector A (51P) terminal No. 21: There should be continuity.
  • Faulty under-dash fuse/relay box
  • An open or high resistance in the wire
Disconnect the 12 volt battery negative terminal Measure the resistance between the terminal and body ground: There should be more than 50 kΩ.
  • Faulty under-dash fuse/relay box
  • Poor ground (G401)
  • An open or high resistance in the ground wire

5. Reconnect the connector to the immobilizer-keyless control unit, do the following input tests:

NOTE:  After replacing the immobilizer-keyless control unit, and do the immobilizer key registration .

Cavity Wire Terminal name Test condition Test: Desired result Possible cause if desired result is not obtained
7 RED +B BACK UP Under all conditions Measure the voltage to ground: There should be battery voltage.
  • Blown No. B29 (10 A) fuse in the under-hood fuse/relay box
  • An open or high resistance in the wire
6 WHT IG1 FUEL PUMP Vehicle ON mode. Measure the voltage to ground: There should be battery voltage.
  • Blown No. C32 (15 A) fuse in the under-dash fuse/relay box
  • An open or high resistance in the wire
1 BLK GND In all power mode s Measure the voltage to ground: There should be less than 0. 2 V.
  • Poor ground (G401)
  • An open or high resistance in the ground wire
3 LT BLU K LINE Under all conditions Measure the voltage to ground: There should be pulse voltage (digital signal).
  • Faulty control unit on the K LINE
  • Short to ground in the K LINE wire