Keyless Access System Symptom Troubleshooting - Cannot select ON mode with keyless access and with the keyless remote touching the engine start/stop switch (With SBW Shifter)

WARNING: This page is about a different car, the 2022 Honda Accord, 2021 Honda Accord, 2020 Honda Accord, 2019 Honda Accord, and 2018 Honda Accord. However, it is still accessible from the selected car via links, so may be relevant.

Cannot select ON mode with keyless access and with the keyless remote touching the engine start/stop switch

Keyless access system check 1
-1. Do this procedure 10 times: Turn the vehicle to the ON mode.

Does the system change to ON mode?

YES

Intermittent failure, the system is OK at this time. Check for loose or poor connection.

NO

Go to step 2.
Keyless access system check 2
-1. Touch the engine start/stop switch with the keyless remote. The buttons on the keyless remote should be facing you.

-2. Turn the vehicle to the ON mode.

Does the system change to ON mode?

YES

Go to keyless access system symptom troubleshooting "Cannot select ON mode with keyless access, but can select ON mode with the keyless remote touching the engine start/stop switch" .

NO

Go to step 3.
Keyless access system check 3
-1. Select KEYLESS ACCESS CONTROL UNIT from the ONE-PUSH START system select menu with the HDS, and enter SELF CHECK.

SELF CHECK

Does the system communicate with the HDS?

YES

Go to step 4.

NO

Go to step 9.
Keyless access system check 4
-1. Reboot the HDS.

-2. Select model on the HDS screen.

-3. When prompted by the HDS, select YES when asked if the vehicle has keyless access system, then press and hold the engine start/stop button for at least 2 minutes. This selects the forced ON mode.

Does the system change to forced ON mode?

YES

Go to step 5.

NO

Go to step 14.

DTC check

-1. Check for DTCs with the HDS.

Keyless access backup control unit

DTC Description	DTC

Keyless access power control unit

DTC Description	DTC

Keyless access control unit

DTC Description	DTC

Are any DTCs indicated?

YES

Troubleshoot the indicated DTCs.

Go to step 6.

Keyless access system check 5
-1. Do the keyless access remote check using all the keyless remotes .

Are the all keyless remotes OK?

YES

Go to step 7.

NO

Replace the keyless remote and recheck.
Keyless access system check 6
-1. Turn the vehicle to the OFF (LOCK) mode.

-2. Remove all the keyless remotes from inside the vehicle. Place the keyless remotes more than 1.5 m (4.9 ft) away from the vehicle.

-3. Disconnect the TCM connector A (23P).

-4. When prompted by the HDS, select YES when asked if the vehicle has keyless access system, then press and hold the engine start/stop button for at least 2 minutes. This selects the forced ON mode.

-5. Do the registration of the body control module according to the instructions on the HDS screen.

-6. Select REGISTRATION from the ONE-PUSH START system select menu with the HDS, then select REPLACE PCU/BACKUP CONTROL/KEYLESS ACCESS CONTROL UNIT.

-7. Reconnect the TCM connector A (23P).

-8. Take the keyless remote into the vehicle, and clear the PCU DTCs with the HDS.

-9. Do this procedure 10 times: Turn the vehicle to the ON mode.

Does the system change to ON mode?

YES

Intermittent failure, the system is OK at this time. Check for loose or poor connection.

NO

Go to step 8.
Body control module check (substitution)
-1. Substitute a known-good body control module .

-2. Do the registration of the body control module according to the instructions on the HDS screen.

-3. Select REGISTRATION from the ONE-PUSH START system select menu with the HDS, then select REPLACE PCU/BACKUP CONTROL/KEYLESS ACCESS CONTROL UNIT.

-4. Recheck the system.

Is the system normal?

YES

Replace the original body control module .

NO

Replace the TCM .
L-line check
-1. Do the DLC circuit troubleshooting .

Is L-line OK?

YES

Go to step 10.

NO

Repair the L-line wire circuit.
Engine start/stop switch operation check
-1. Do the engine start/stop switch test .

Is the engine start/stop switch OK?

YES

Go to step 11.

NO

Replace the engine start/stop switch .

Open wire check (SS1 (+), SS2 (-) lines)

-1. Disconnect the following connector.

Body control module connector C (66P)

-2. Check for continuity between test points 1 and 2 respectively.

Test condition

Vehicle OFF (LOCK) mode Engine start/stop switch 10P connector: disconnected Body control module connector C (66P): disconnected

Test point 1	Engine start/stop switch 10P connector (female terminals) No. 6:
Test point 2	Body control module connector C (66P) No. 63

Test point 1	Engine start/stop switch 10P connector (female terminals) No. 10:
Test point 2	Body control module connector C (66P) No. 5

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

Is there continuity?

YES

The SS1 (+) and SS2 (-) wires are OK. Go to step 12.

Repair an open or high resistance in the wire.

Open wire check (+B SMART line)

-1. Measure the voltage between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode Engine start/stop switch 10P connector: disconnected Body control module connector C (66P): disconnected
Test point 1	Engine start/stop switch 10P connector (female terminals) No. 5:
Test point 2	Body ground

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

Is there battery voltage?

YES

The +B SMART wire is OK. Go to step 13.

Repair an open or high resistance in the wire. If wire is OK, check the No. B9 fuse circuit.

Open wire check (GND line)

-1. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode Engine start/stop switch 10P connector: disconnected Body control module connector C (66P): disconnected
Test point 1	Engine start/stop switch 10P connector (female terminals) No. 1:
Test point 2	Body ground

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

Is there continuity?

YES

The GND wire is OK. Go to step 15.

Repair an open or high resistance in the ground wire or poor ground (G503).

PCU DTC check

-1. Check for PCU DTCs with the HDS.

DTC Description	DTC

Are any DTCs indicated?

YES

Troubleshoot the PCU DTCs.

Go to step 15.

Open wire check (+B BACK UP, +B SMART lines)

-1. Disconnect the following connectors.

Body control module connector A (66P)Body control module connector C (66P)

-2. Measure the voltage between test points 1 and 2 individually.

Test condition	Vehicle OFF (LOCK) mode Engine start/stop switch 10P connector: disconnected Body control module connector A (66P): disconnected Body control module connector C (66P): disconnected
Test point 1	Body control module connector A (66P) No. 1
Test point 2	Body ground

Test point 1	Body control module connector C (66P) No. 13
Test point 2	Body ground

Is there battery voltage?

YES

The +B BACK UP and +B SMART wires are OK. Go to step 16.

Repair an open or high resistance in the wire.

Open wire check (GND line)

-1. Disconnect the following connector.

Body control module connector B (66P)

-2. Check for continuity between test points 1 and 2 individually.

Test condition	Vehicle OFF (LOCK) mode Engine start/stop switch 10P connector: disconnected Body control module connector A (66P): disconnected Body control module connector B (66P): disconnected Body control module connector C (66P): disconnected
Test point 1	Body control module connector A (66P) No. 56
Test point 2	Body ground

Test point 1	Body control module connector B (66P) No. 2
Test point 2	Body ground

Test point 1	Body control module connector B (66P) No. 35
Test point 2	Body ground

Is there continuity?

YES

The GND wires are OK. Go to step 17.

Repair an open or high resistance in the ground wire or poor ground (G501, G502).

Open wire check (between body control module and TCM lines)

-1. Disconnect the following connector.

TCM connector A (23P)

-2. Check for continuity between test points 1 and 2 as shown.

Test condition

Vehicle OFF (LOCK) mode Engine start/stop switch 10P connector: disconnected Body control module connector A (66P): disconnected Body control module connector B (66P): disconnected Body control module connector C (66P): disconnected TCM connector A (23P): disconnected

Test circuit	Test point 1: Body control module connector	Test point 2: TCM connector A (23P)
ESL PWR/TCUWUP/ACC	C42	A4
IGN TRX/IGNTRX	C35	A17

Is there continuity?

YES

The wires between the body control module and TCM are not open. Go to step 18.

Repair an open or high resistance in the wire.

Shorted wire check (between TCM and body ground)

-1. Check for continuity between the following test points and body ground as shown.

Test condition

Connector	Test circuit	Terminal
TCM connector A (23P)	TCUWUP/ACC	A4
TCM connector A (23P)	IGNTRX	A17

Is there continuity?

YES

Repair a short to ground in the wire.

The wires between the TCM and body ground are OK. Go to step 19.

Open wire check (VB1, VB2, VB3 lines)

-1. Measure the voltage between test points 1 and 2 individually.

Test condition	Vehicle OFF (LOCK) mode Engine start/stop switch 10P connector: disconnected Body control module connector A (66P): disconnected Body control module connector B (66P): disconnected Body control module connector C (66P): disconnected TCM connector A (23P): disconnected

Test point 1	TCM connector A (23P) No. 15
Test point 2	Body ground

Test point 1	TCM connector A (23P) No. 23
Test point 2	Body ground

Test point 1	TCM connector A (23P) No. 8
Test point 2	Body ground

Is there battery voltage?

YES

The VB1, VB2, and VB3 wires are OK. Go to step 20.

Repair an open or high resistance in the wire.

Open wire check (IG1 line)

-1. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode Engine start/stop switch 10P connector: disconnected Body control module connector A (66P): disconnected Body control module connector B (66P): disconnected Body control module connector C (66P): disconnected TCM connector A (23P): disconnected

Test point 1	TCM connector A (23P) No. 6
Test point 2	Body ground

Is there continuity?

YES

The IG1 wire is OK. Go to step 21.

Repair an open or high resistance in the wire. If wire is OK, check the No. A39 fuse circuit.

Open wire check (LG1, LG2, PG1, PG2 lines)

-1. Disconnect the following connector.

TCM connector B (45P)

-2. Check for continuity between test points 1 and 2 individually.

Test condition	Vehicle OFF (LOCK) mode Engine start/stop switch 10P connector: disconnected Body control module connector A (66P): disconnected Body control module connector B (66P): disconnected Body control module connector C (66P): disconnected TCM connector A (23P): disconnected TCM connector B (45P): disconnected

Test point 1	TCM connector A (23P) No. 1
Test point 2	Body ground

Test point 1	TCM connector A (23P) No. 9
Test point 2	Body ground

Test point 1	TCM connector B (45P) No. 17
Test point 2	Body ground

Test point 1	TCM connector B (45P) No. 35
Test point 2	Body ground

Is there continuity?

YES

The LG1, LG2, PG1, and PG2 wires are OK. Go to step 22.

Repair an open or high resistance in the ground wire or poor ground (G251, G303).

Body control module check (substitution)
-1. Substitute a known-good body control module .

-2. Reconnect these items:

Engine start/stop switch 10P connectorBody control module connector A (66P)Body control module connector B (66P)Body control module connector C (66P)TCM connector A (23P): disconnected TCM connector B (45P): disconnected

-3. Do the registration of the body control module according to the instructions on the HDS screen.

-4. Select REGISTRATION from the ONE-PUSH START system select menu with the HDS, then select REPLACE PCU/BACKUP CONTROL/KEYLESS ACCESS CONTROL UNIT.

-5. Turn the vehicle to the ON mode.

Does the system change to ON mode?

YES

Replace the original body control module .

NO

Replace the TCM .