DTC U0122-00 (E-Pretensioner Unit) (2014 2015)

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DTC U0122-00 : Lost Communication With the VSA Modulator-Control 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
U0122-00 Lost Communication With the VSA Modulator-Control Unit

DTC Description	DTC
U0122-00 Lost Communication With the VSA Modulator-Control 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?

VSA MODULATOR-CONTROL UNIT (Bus B) is Not Available

Go to step 3.

VSA MODULATOR-CONTROL 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.

VSA MODULATOR-CONTROL 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

VSA modulator-control unit 38P connector

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

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 24P connector: disconnected
	VSA modulator-control unit 38P connector: disconnected
Test circuit	F-CAN B_L
Test point 1	CAN gateway 24P connector No. 10 (GRY)
Test point 2	VSA modulator-control unit 38P connector No. 26 (GRY)

Test circuit	F-CAN B_H
Test point 1	CAN gateway 24P connector No. 11 (LT BLU)
Test point 2	VSA modulator-control unit 38P connector No. 38 (LT BLU)

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 VSA modulator-control unit. Update the VSA modulator-control unit if it does not have the latest software, then retest. If the DTC is still present, replace the VSA modulator-control unit .

Repair an open in the wire between the VSA modulator-control 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

VSA modulator-control unit 38P connector

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

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 24P connector: disconnected
	VSA modulator-control unit 38P connector: disconnected
Test circuit	F-CAN C_L
Test point 1	CAN gateway 24P connector No. 8 (PNK)
Test point 2	VSA modulator-control unit 38P connector No. 20 (PNK)

Test circuit	F-CAN C_H
Test point 1	CAN gateway 24P connector No. 9 (PUR)
Test point 2	VSA modulator-control unit 38P connector No. 31 (PUR)

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 VSA modulator-control unit. Update the VSA modulator-control unit if it does not have the latest software, then retest. If the DTC is still present, replace the VSA modulator-control unit .

Repair an open in the wire between the VSA modulator-control 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.