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MICU Input Test

NOTE: 

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

2. Disconnect under-dash fuse/relay box connectors D, G, H, N, and Q.

NOTE:  All connector views are shown from the wire side of the female terminals.

GHH82249Courtesy 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
G2 PNK Disconnect the gauge control module 32P connector Check for continuity between terminal G2 and gauge control module 32P connector terminal No. 23: There should be continuity. An open in the B-CAN wire
G3 BLU Check for continuity between terminal G3 and gauge control module 32P connector terminal No. 24: There should be continuity.
G2 PNK Disconnect the climate control unit 32P connector Check for continuity between terminal G2 and climate control unit 32P connector terminal No. 6: There should be continuity. An open in the B-CAN wire
G3 BLU Check for continuity between terminal G3 and climate control unit 32P connector terminal No. 7: There should be continuity.
G2 PNK Disconnect the automatic lighting control unit/sensor 7P connector Check for continuity between terminal G2 and automatic lighting control unit/sensor 7P connector terminal No. 6: There should be continuity. An open in the B-CAN wire
G3 BLU Check for continuity between terminal G3 and automatic lighting control unit/sensor 7P connector terminal No. 7: There should be continuity.
G2*1 PNK Disconnect the immobilizer-keyless control unit 7P connector Check for continuity between terminal G2 and immobilizer-keyless control unit 7P connector terminal No. 4: There should be continuity. An open in the B-CAN wire
G3*1 BLU Check for continuity between terminal G3 and immobilizer-keyless control unit 7P connector terminal No. 5: There should be continuity.
G2*2 PNK Disconnect keyless access control unit connector C (20P) Check for continuity between terminal G2 and keyless access control unit connector C (20P) terminal No. 1: There should be continuity. An open in the B-CAN wire
G3*2 BLU Check for continuity between terminal G3 and keyless access control unit connector C (20P) terminal No. 11: There should be continuity.
G2*3 PNK Disconnect audio unit connector B (20P) Check for continuity between terminal G2 and audio unit connector B (20P) terminal No. 13: There should be continuity. An open in the B-CAN wire
G3*3 BLU Check for continuity between terminal G3 and audio unit connector B (20P) terminal No. 3: There should be continuity.
G2*4 PNK Disconnect audio unit connector C (24P) Check for continuity between terminal G2 and audio unit connector C (24P) terminal No. 24: There should be continuity. An open in the B-CAN wire
G3*4 BLU Check for continuity between terminal G3 and audio unit connector C (24P) terminal No. 12: There should be continuity.
G2*5 PNK Disconnect audio-navigation unit connector B (20P) Check for continuity between terminal G2 and audio-navigation unit connector B (20P) terminal No. 13: There should be continuity. An open in the B-CAN wire
G3*5 BLU Check for continuity between terminal G3 and audio-navigation unit connector B (20P) terminal No. 3: There should be continuity.
D13 LT BLU Under all conditions Check for continuity between terminal D13 and data link connector (DLC) terminal No. 7: There should be continuity. An open in the K LINE wire

*1: Without keyless access system

*2: With keyless access system

*3: With display audio

*4: With color audio

*5: With navigation

5. Reconnect the connectors to the under-dash fuse/relay box, and do the following input tests:

Cavity Wire Test condition Test: Desired result Possible cause if desired result is not obtained
Q15 RED 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
  • Faulty under-hood fuse/relay box
  • An open or high resistance in the wire
D23 BLK In all power modes 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
H1 BLK In all power modes 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
N6 BLK 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
N38 BLK 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