DTC U0146 (CVT (TCM))

DTC U0146  : F-CAN Malfunction (TCM-CAN Gateway)

NOTE: 

• Before you troubleshoot, review the General Troubleshooting Information .
• This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.
• According to the detected DTC (s), check for the power circuit of the CAN gateway.

DTC (CVT)

1. CAN gateway system DTC check

   -1. Check for CAN gateway system DTCs with the HDS.

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

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

   YES 

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

   NO 

   Go to step 2.

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?

   TCM (Bus A) is Not Available

   Go to step 3.

   TCM is Detected

   Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the CAN gateway and the TCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.

3. Open wire check (F-CAN A_H line, F-CAN A_L line)

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

   -2. Disconnect the following connectors.

   CAN gateway 16P connector

   TCM connector (50P)

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

   Test condition	Vehicle OFF (LOCK) mode
   	CAN gateway 16P connector: disconnected
   	TCM connector (50P): disconnected
   Test point 1	CAN gateway 16P connector (female terminals) No. 3:
   Test point 2	TCM connector (50P) No. 3

   Test point 1	CAN gateway 16P connector (female terminals) No. 11:
   Test point 2	TCM connector (50P) No. 11

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

   Is there continuity?

   YES 

   The F-CAN A_H wire and the F-CAN A_L wire are OK. Check for poor connections or loose terminals at the CAN gateway and the TCM. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting, or substitute a known-good TCM , then recheck. If this DTC goes away and the TCM was substituted, replace the original TCM .

   NO 

   Repair an open in the wire between the TCM and the CAN gateway.