Keyless/Power Door Locks/Security System (MICU, Door Multiplex Control Unit, and Front Passenger's Power Window Switch) Input Test (2020 2021 2022 2023 2024 2025)

NOTE:

If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A .
Before testing, make sure the fuses and relays associated with the system are OK.
Before testing, make sure the headlights, parking lights, side marker lights, taillights, and horns work properly.
There are two pairs of fuses in the same circuit (No. C34 and No. C35 fuses, No. C19 and No. C41 fuses, No. C20 and No. C33 fuses). If one fuse is blown, make sure to check the other fuse in the same circuit. If necessary, replace the blown fuse(s).

MICU

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

2. Disconnect under-dash fuse/relay box connectors.

UNDER-DASH FUSE/RELAY BOX CONNECTOR D (44P) (female terminals):

UNDER-DASH FUSE/RELAY BOX CONNECTOR E (36P) (female terminals):

UNDER-DASH FUSE/RELAY BOX CONNECTOR F (18P) (female terminals):

UNDER-DASH FUSE/RELAY BOX CONNECTOR M (12P) (female terminals):

UNDER-DASH FUSE/RELAY BOX CONNECTOR P (24P) (female terminals):

UNDER-DASH FUSE/RELAY BOX CONNECTOR S (18P) (female terminals):

UNDER-DASH FUSE/RELAY BOX CONNECTOR T (10P) (female terminals):

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

3. Inspect the connectors 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, do the following input tests:

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.

NOTE: These are door lock actuator operation tests for keyless entry.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
T6	RED	Connect battery power* to T6 (or T5), and terminal T5 (or T6) and ground with jumper wires.	Check actuator operation: The driver's door lock actuator should LOCK (or UNLOCK).	Faulty driver's door lock actuator An open or high resistance in the wire
T5	TAN
S2	LT GRN	Connect battery power* to S2 (or S5), and terminal S5 (or S2) and ground with jumper wires.	Check actuator operation: The front passenger's door lock actuator and right rear door lock actuator should LOCK (or UNLOCK).	Faulty front passenger's door lock actuator Faulty right rear door lock actuator An open or high resistance in the wire
S5	TAN
D11	RED	Connect battery power* to D11 (or D12), and terminal D12 (or D11) and ground with jumper wires.	Check actuator operation: The left rear door lock actuator should LOCK (or UNLOCK).	Faulty left rear door lock actuator An open or high resistance in the wire
D12	YEL
D17	BLK	Connect battery power* to D17 with a jumper wire.	Check actuator operation: The tailgate release actuator should work.	Faulty in-bed trunk lid release actuator Poor ground (G701) or an open in the ground wire An open or high resistance in the wire
E31	BLU	Under all conditions	Connect to ground with a jumper wire: The horns should sound.	Faulty horn relay Faulty horn An open or high resistance in the wire
P22	LT BLU	Keyless access/TPMS control unit connector A (32P) disconnected	Check for continuity between terminal P22 and the keyless access/TPMS control unit connector A (32P) terminal No. 2: There should be continuity.	An open or high resistance in the wire

*: Use a fused jumper wire with an appropriate amperage fuse.

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

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 6.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
M9	WHT	Under all conditions	Measure the voltage to ground: There should be battery voltage.	An open or high resistance in the wire
F2	WHT	Under all conditions	Measure the voltage to ground: There should be battery voltage.	An open or high resistance in the wire
E32	BRN	Vehicle ON mode	Measure the voltage to ground: There should be battery voltage.	An open or high resistance in the wire
D14	BLK	In all power modes	Measure the voltage to ground: There should be less than 0.2 V.	Poor ground (G601) An open or high resistance in the ground wire
D42	BLK	In all power modes	Measure the voltage to ground: There should be less than 0.2 V.	Poor ground (G601) An open or high resistance in the ground wire

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
P1	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
F7	BLK	In all power modes	Measure the voltage to ground: There should be less than 0.2 V.	Poor ground (G352) An open or high resistance in the ground wire
D35	LT BLU	Driver's door open	Measure the voltage to ground: There should be less than 0.2 V.	Faulty driver's door switch Faulty driver's door switch ground An open or high resistance in the wire
D35	LT BLU	Driver's door closed	Measure the voltage to ground: There should be about 5 V.	Faulty driver's door switch A short to ground in the wire Faulty MICU
D37	BLU	Front passenger's door open	Measure the voltage to ground: There should be less than 0.2 V.	Faulty front passenger's door switch Faulty front passenger's door switch ground An open or high resistance in the wire
D37	BLU	Front passenger's door closed	Measure the voltage to ground: There should be about 5 V.	Faulty front passenger's door switch A short to ground in the wire Faulty MICU
D34	PNK	Left rear door open	Measure the voltage to ground: There should be less than 0.2 V.	Faulty left rear door switch Faulty left rear door switch ground An open or high resistance in the wire
D34	PNK	Left rear door closed	Measure the voltage to ground: There should be about 5 V.	Faulty left rear door switch A short to ground in the wire Faulty MICU
D28	GRN	Right rear door open	Measure the voltage to ground: There should be less than 0.2 V.	Faulty right rear door switch Faulty right rear door switch ground An open or high resistance in the wire
D28	GRN	Right rear door closed	Measure the voltage to ground: There should be about 5 V.	Faulty right rear door switch A short to ground in the wire Faulty MICU
D25	LT BLU	Left rear door lock knob switch in UNLOCK	Measure the voltage to ground: There should be less than 0.2 V.	Faulty left rear door lock knob switch Poor ground (G601) or an open in the ground wire An open or high resistance in the wire
D25	LT BLU	Left rear door lock knob switch in LOCK	Measure the voltage to ground: There should be about 5 V.	Faulty left rear door lock knob switch A short to ground in the wire Faulty MICU

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
D26	YEL	Right rear door lock knob switch in UNLOCK	Measure the voltage to ground: There should be less than 0.2 V.	Faulty right rear door lock knob switch Poor ground (G603) or an open in the ground wire An open or high resistance in the wire
D26	YEL	Right rear door lock knob switch in LOCK	Measure the voltage to ground: There should be about 5 V.	Faulty right rear door lock knob switch A short to ground in the wire Faulty MICU
P19	PNK	In-bed trunk lid open	Measure the voltage to ground: There should be less than 0.2 V	Faulty in-bed trunk lid latch switch Poor ground (G701) or an open in the ground wire An open or high resistance in the wire
P19	PNK	In-bed trunk lid closed	Measure the voltage to ground: There should be about 5 V.	Faulty in-bed trunk lid latch switch A short to ground in the wire
F16	GRN	Hood closed	Measure the voltage to ground: There should be less than 0.2 V.	Faulty hood latch switch Poor ground (G251) or an open in the ground wire An open or high resistance in the wire
F16	GRN	Hood open	Measure the voltage to ground: There should be about 5 V.	Faulty hood latch switch A short to ground in the wire Faulty MICU
E27	BLU	Transmission in P position/mode	Measure the voltage to ground: There should be less than 0.2 V.	Faulty SBW shifter Faulty TCM An open or high resistance in the wire
E27	BLU	Transmission in any position/mode other than P	Measure the voltage to ground: There should be about 5 V.	Faulty SBW shifter Faulty TCM A short to ground in the wire Faulty MICU

Door Multiplex Control Unit

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

7. Disconnect the power window master switch 37P connector.

POWER WINDOW MASTER SWITCH 37P CONNECTOR (female terminals)

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

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

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 9.

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

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 10.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
36	GRY	Disconnect the front passenger's power window switch 24P connector and the moonroof motor-control unit 14P connector*	Check for continuity between terminal No. 36 and front passenger's power window switch 24P connector terminal No. 24: There should be continuity.	An open or high resistance in the wire
			Check for continuity between terminal No. 36 and moonroof control unit/motor 14P connector terminal No. 12: There should be continuity.	An open or high resistance in the wire
			Check for continuity to ground: There should be no continuity.	A short to ground in the wire

*: With moonroof

10. Reconnect the connector, do the following input tests:

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 11.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
25	LT GRN	Vehicle ON mode	Measure the voltage to ground: There should be battery voltage.	An open or high resistance in the wire
26	WHT	Under all conditions	Measure the voltage to ground: There should be battery voltage.	An open or high resistance in the wire
4	WHT	Under all conditions	Measure the voltage to ground: There should be battery voltage.	An open or high resistance in the wire
3	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
31	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
35	PNK	Driver's door key cylinder switch in LOCK	Measure the voltage to ground: There should be less than 0.2 V.	Faulty driver's door key cylinder switch Poor ground (G401) or an open in the ground wire An open or high resistance in the wire
35	PNK	Driver's door key cylinder switch in neutral or UNLOCK	Measure the voltage to ground: There should be about 5 V.	Faulty driver's door key cylinder switch A short to ground in the wire Faulty power window master switch

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
34	BRN	Driver's door key cylinder switch in UNLOCK	Measure the voltage to ground: There should be less than 0.2 V.	Faulty driver's door key cylinder switch Poor ground (G401) or an open in the ground wire An open or high resistance in the wire
34	BRN	Driver's door key cylinder switch in neutral or LOCK	Measure the voltage to ground: There should be about 5 V.	Faulty driver's door key cylinder switch An open or high resistance in the wire Faulty power window master switch
33	YEL	Driver's door lock knob switch in LOCK	Measure the voltage to ground: There should be less than 0.2 V.	Faulty driver's door lock knob switch Poor ground (G401) or an open in the ground wire An open or high resistance in the wire
33	YEL	Driver's door lock knob switch in UNLOCK	Measure the voltage to ground: There should be about 5 V.	Faulty driver's door lock knob switch A short to ground in the wire Faulty power window master switch
32	GRN	Driver's door lock knob switch in UNLOCK	Measure the voltage to ground: There should be less than 0.2 V.	Faulty driver's door lock knob switch Poor ground (G401) or an open in the ground wire An open or high resistance in the wire
32	GRN	Driver's door lock knob switch in LOCK	Measure the voltage to ground: There should be about 5 V.	Faulty driver's door lock knob switch A short to ground in the wire Faulty power window master switch

Front Passenger's Power Window Switch

11. Turn the vehicle to the OFF (LOCK) mode, open and close the driver's door.

12. Disconnect the front passenger's power window switch 37P connector.

FRONT PASSENGER'S POWER WINDOW SWITCH 24P CONNECTOR (female terminals)

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

13. Inspect the 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 14.

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

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 15.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
24	GRY	Disconnect the power window master switch 37P connector and the moonroof motor-control unit 14P connector*	Check for continuity between terminal No. 24 and power window master switch 37P connector terminal No. 36: There should be continuity.	An open or high resistance in the wire
			Check for continuity between terminal No. 24 and moonroof motor-control unit 14P connector terminal No. 12: There should be continuity.	An open or high resistance in the wire
			Check for continuity to ground: There should be no continuity.	A short to ground in the wire

*: With moonroof

15. Reconnect the connector, do the following input tests:

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 16.

Cavity	Wire	Test condition	Test: Desired result	Possible cause if desired result is not obtained
14	GRN	Under all conditions	Measure the voltage to ground: There should be battery voltage.	An open or high resistance in the wire
9	BLK	In all power modes	Measure the voltage to ground: There should be less than 0.2 V.	Poor ground (G405) An open or high resistance in the ground wire
11	BLU	Front passenger's door lock knob switch in UNLOCK	Measure the voltage to ground: There should be less than 0.2 V.	Front passenger's door lock knob switch Poor ground (G405) or an open in the ground wire An open or high resistance in the wire
11	BLU	Front passenger's door lock knob switch in LOCK	Measure the voltage to ground: There should be about 5 V.	Front passenger's door lock knob switch A short to ground in the wire Faulty front passenger's power window switch

16. If multiple failures are found on more than one control unit, replace the under-dash fuse/relay box (includes the MICU) . If input failures are related to a particular control unit, replace the control unit.