DTC U0101-00, U0155-00

DTC U0101-00 : Lost Communication With the PCM (PGM-FI system)

DTC U0155-00 : Lost Communication With the Gauge Control Module

NOTE:

Before doing this troubleshooting procedure, find out if the vehicle was in a collision. If so, verify that all the required components were replaced with new components of the correct part number and were properly installed .
Before doing this troubleshooting procedure, review SRS Precautions and Procedures , General Troubleshooting Information , and 12 Volt Battery Terminal Disconnection and Reconnection .
According to the detected DTC(s), check for the power circuit and the ground circuit of the control unit which cannot communicate with the SRS unit.
Refer to the DTC shown on the display, then inspect the connectors and terminals based on the instructions.

DTC Description	DTC
U0101-00 Lost communication with the PCM (PGM-FI system)
U0155-00 Lost communication with the gauge control module

DTC (SRS)

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

Are any DTCs indicated?

YES

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

Go to step 2.

F-CAN circuit communication check (Receiving control unit)
-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

Does the SRS unit detect the CAN gateway Bus channels A?

Bus A is Not Available

Go to step 3.

Bus A is Available

Go to step 4.

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

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

-2. Disconnect the negative cable from the 12 volt battery, then wait at least 3 minutes.

-3. Disconnect the following connectors.

CAN gateway 16P connector

SRS unit connector A (39P)

-4. Check for continuity between test points 1 and 2.

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 16P connector: disconnected
	SRS unit connector A (39P): disconnected
Test point 1	CAN gateway 16P connector (female terminals) No. 3:
Test point 2	SRS unit connector A (39P) No. 20

Test point 1	CAN gateway 16P connector (female terminals) No. 11:
Test point 2	SRS unit connector A (39P) No. 21

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

Is there continuity?

YES

The F-CAN A_H and the F-CAN A_L wires are OK. Check for poor connections or loose terminals at the CAN gateway and the SRS unit. If the connection is OK, check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or replace the SRS unit .

Replace an open in the wire between the CAN gateway and the SRS unit.

F-CAN circuit communication check (Transmitting control unit)

-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

According to the detected DTC on the following table, make sure that the transmitting control unit detects the CAN gateway Bus channel(s) normally.

DTC	Transmitting control unit	Detected CAN gateway Bus channel(s) at normal
U0101-00	PCM	A
U0155-00	Gauge control module	B

Is it detected normally?

Detected normal

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the transmitting control unit and the CAN gateway.

U0101-00: PCM is Not Available for Bus A

Go to step 5.

U0155-00: Gauge control module is Not Available for Bus B

Go to step 6.

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

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

-2. According to the detected DTC on the following table, disconnect the transmitting control unit connector(s).

DTC	Connector
-	CAN gateway 16P connector
U0101-00	PCM connector A (51P)

NOTE: Before disconnecting the PCM connector A (51P), jump the SCS line with the HDS, and wait more than 1 minute.

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

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 16P connector: disconnected
	Transmitting control unit connector(s) for indicated DTCs: disconnected

DTC	Circuit name	Test point 1 (Receiving control unit)		Test point 2 (Transmitting control unit)
DTC	Circuit name	Connector	Terminal	Connector	Terminal
U0101-00	F-CAN A_H	CAN gateway 16P connector (female terminals):	No. 3	PCM connector A (51P)	No. 2
U0101-00	F-CAN A_L	CAN gateway 16P connector (female terminals):	No. 11	PCM connector A (51P)	No. 3

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

Is there continuity?

YES

The F-CAN A_H and the F-CAN A_L wires are OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting.

According to the detected DTC on the following table, substitute or replace the corresponding control unit.

DTC	Operation for transmitting control unit
U0101-00	Check for poor connections or loose terminals at the CAN gateway and the PCM. Substitute a known-good PCM , then recheck. If DTC U0101-00 goes away and the PCM was substituted, replace the original PCM .

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

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

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

-2. According to the detected DTC on the following table, disconnect the transmitting control unit connector(s).

DTC	Connector
-	CAN gateway 16P connector
U0155-00	Gauge control module 32P connector

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

Test condition	Vehicle OFF (LOCK) mode
	CAN gateway 16P connector: disconnected
	Transmitting control unit connector(s) for indicated DTCs: disconnected

DTC	Circuit name	Test point 1 (Receiving control unit)		Test point 2 (Transmitting control unit)
DTC	Circuit name	Connector	Terminal	Connector	Terminal
U0155-00	F-CAN B_H	CAN gateway 16P connector (female terminals):	No. 6	Gauge control module 32P connector (female terminals):	No. 27
U0155-00	F-CAN B_L	CAN gateway 16P connector (female terminals):	No. 14	Gauge control module 32P connector (female terminals):	No. 28

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

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

Is there continuity?

YES

The F-CAN B_H and the F-CAN B_L wires are OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting.

According to the detected DTC on the following table, substitute or replace the corresponding control unit.

DTC	Operation for transmitting control unit
U0155-00	Check for poor connections or loose terminals at the CAN gateway and the gauge control module. Substitute a known-good gauge control module , then recheck. If DTC U0155-00 goes away and the gauge control module was substituted, replace the original gauge control module .

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