DTC U0104-00 (E-Pretensioner Unit) (2014 2015)

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DTC U0104-00 : Lost Communication With the ACC Unit

NOTE:

Before doing this troubleshooting procedure, review General Troubleshooting Information .
Before replacing the E-pretensioner unit, check the E-pretensioner unit software version with the HDS. If the software version is not the latest, update the E-pretensioner unit software , and retest.

DTC Description	DTC
U0104-00 Lost Communication With the ACC Unit

DTC Description	DTC
U0104-00 Lost Communication With the ACC Unit

DTC (E-pretensioner)

CAN gateway system DTC check

-1. Turn the vehicle to the ON mode.

-2. Check for CAN gateway system DTCs with the HDS.

DTC Description	DTC
U0029-00 CAN Gateway F-CAN ch A Bus Off
U0047-00 CAN Gateway F-CAN ch B Bus Off
U0056-00 CAN Gateway F-CAN ch C Bus Off
U3000-49 CAN Gateway Internal Failure

Is DTC U0029-00, U0047-00, U0056-00, and/or U3000-49 indicated?

YES

Go to the troubleshooting for CAN gateway system DTC (s) .

Go to step 2.

F-CAN circuit communication check
-1. Select the FUNCTION TEST in the CAN gateway with the HDS, then select the F-CAN Bus Connected Unit Check.

F-CAN Bus Connected Unit Check

Which result is indicated?

ACC UNIT (Bus B) is Not Available

Go to step 3.

ACC UNIT (Bus C) is Not Available

Go to step 4.

DRIVER'S E-PRETENSIONER UNIT is Not Available

Go to step 5.

FRONT PASSENGER'S E-PRETENSIONER UNIT is Not Available

Go to step 6.

ACC UNIT and E-PRETENSIONER UNITs are Detected

Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting.

Open wire check (F-CAN B_H, F-CAN B_L lines)

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

-2. Disconnect the following connectors.

CAN gateway 24P connector

ACC unit 20P connector

-3. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 24P connector: disconnected
	ACC unit 20P connector: disconnected
Test circuit	F-CAN B_H
Test point 1	CAN gateway 24P connector No. 11 (LT BLU)
Test point 2	ACC unit 20P connector No. 2 (LT BLU)

Test circuit	F-CAN B_L
Test point 1	CAN gateway 24P connector No. 10 (GRY)
Test point 2	ACC unit 20P connector No. 13 (GRY)

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

Is there continuity?

YES

The F-CAN B_H and F-CAN B_L wires are OK. Check for poor connections or loose terminals at the CAN gateway and the ACC unit. Update the ACC unit if it does not have the latest software, then retest. If the DTC is still present, replace the ACC unit .

Repair an open in the wire between the ACC unit and the CAN gateway.

Open wire check (F-CAN C_H, F-CAN C_L lines)

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

-2. Disconnect the following connectors.

CAN gateway 24P connector

ACC unit 20P connector

-3. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 24P connector: disconnected
	ACC unit 20P connector: disconnected
Test circuit	F-CAN C_H
Test point 1	CAN gateway 24P connector No. 9 (PUR)
Test point 2	ACC unit 20P connector No. 4 (PUR)

Test circuit	F-CAN C_L
Test point 1	CAN gateway 24P connector No. 8 (PNK)
Test point 2	ACC unit 20P connector No. 15 (PNK)

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

Is there continuity?

YES

The F-CAN C_H and F-CAN C_L wires are OK. Check for poor connections or loose terminals at the CAN gateway and the ACC unit. Update the ACC unit if it does not have the latest software, then retest. If the DTC is still present, replace the ACC unit .

Repair an open in the wire between the ACC unit and the CAN gateway.

Open wire check (F-CAN A_H, F-CAN A_L lines)

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

-2. Disconnect the following connectors.

E-pretensioner unit connector A (16P)

CAN gateway 24P connector

-3. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	E-pretensioner unit connector A (16P): disconnected
	CAN gateway 24P connector: disconnected
Test circuit	F-CAN A_H
Test point 1	E-pretensioner unit connector A (16P) No. 12 (BLU)
Test point 2	CAN gateway 24P connector No. 14 (BLU)

Test circuit	F-CAN A_L
Test point 1	E-pretensioner unit connector A (16P) No. 13 (PNK)
Test point 2	CAN gateway 24P connector No. 15 (PNK)

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

Is there continuity?

YES

The F-CAN A_H and F-CAN A_L wires are OK. Replace the E-pretensioner unit .

Repair an open in the wire between the CAN gateway and E-pretensioner unit connector A (16P) of the E-pretensioner unit.

Open wire check (F-CAN A_H, F-CAN A_L lines)

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

-2. Disconnect the following connectors.

E-pretensioner unit connector B (14P)

CAN gateway 24P connector

-3. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	E-pretensioner unit connector B (14P): disconnected
	CAN gateway 24P connector: disconnected
Test circuit	F-CAN A_H
Test point 1	E-pretensioner unit connector B (14P) No. 10 (BLU)
Test point 2	CAN gateway 24P connector No. 14 (BLU)

Test circuit	F-CAN A_L
Test point 1	E-pretensioner unit connector B (14P) No. 11 (PNK)
Test point 2	CAN gateway 24P connector No. 15 (PNK)

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

Is there continuity?

YES

The F-CAN A_H and F-CAN A_L wires are OK. Replace the E-pretensioner unit .

Repair an open in the wire between the CAN gateway and E-pretensioner unit connector B (14P) of the E-pretensioner unit.