DTC U0029: F-CAN Communication Line Error

NOTE:

Make sure the HDS communicates with the ECM/PCM and other vehicle systems. If it does not, go to DLC Circuit Troubleshooting (see DLC CIRCUIT TROUBLESHOOTING ).
If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

Clear the DTCs with the HDS.
Turn the ignition switch to LOCK (0), and then back to ON (II).
Wait for at least 6 seconds.
Check for DTCs with the HDS.
Is DTC U0029 indicated?

YES -Go to step 5.

NO -Intermittent failure, the system is OK at this time. Check for loose or poor connections, or worn/shorted wires. If the connections are good, check the battery condition (see BATTERY TEST ) and the charging system.
Turn the ignition switch to LOCK (0).

Disconnect the appropriate connector at each control unit in the table one at a time. Clear the DTC, then recheck for DTCs after each unit is disconnected.

CONTROL UNIT CONNECTOR TERMINALS CHART

Control Unit

Connector

Gauge control module

32P connector

ECM/PCM

Connector A (49P)

VSA modulator-control unit

32P connector

SRS unit

Connector A (39P)

TPMS control unit

20P connector

EPS control unit

28P connector

Yaw rate-lateral acceleration sensor

4P connector

AcuraLink control unit⁽¹⁾

Connector B (14P)

⁽¹⁾	With AcuraLink

Is DTC U0029 indicated after each individual unit was disconnected?

YES -Go to step 7.

NO -Replace the control unit that was disconnected when DTC U0029 did not set.

Turn the ignition switch to LOCK (0).

Disconnect all the control units connectors in the following table.

CONTROL UNIT CONNECTOR TERMINALS CHART

Control Unit

Connector

Gauge control module

32P connector

ECM/PCM

Connector A (49P)

VSA modulator-control unit

32P connector

SRS unit

Connector A (39P)

TPMS control unit

20P connector

EPS control unit

28P connector

Yaw rate-lateral acceleration sensor

4P connector

AcuraLink control unit⁽¹⁾

Connector B (14P)

⁽¹⁾	With AcuraLink

Disconnect the HDS from the data link connector (DLC).
Check for continuity between body ground and gauge control module 32P connector terminals No. 21 and No. 22 individually.
GAUGE CONTROL MODULE 32P CONNECTOR

Fig 1: Checking Continuity Between Body Ground And Gauge Control Module 32P Connector Terminals No. 21 And No. 22
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair a short to ground in the wire.

NO -Go to step 11.
Check for continuity between gauge control module 32P connector terminals No. 21 and No. 22.

GAUGE CONTROL MODULE 32P CONNECTOR

Fig 2: Checking Continuity Between Gauge Control Module 32P Connector Terminals No. 21 And No. 22

Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Repair a short in the F-CAN wires.

NO -Replace the gauge control module (see GAUGE CONTROL MODULE REPLACEMENT ).