DTC Troubleshooting: U0029-00
DTC U0029-00: F-CAN Bus-Off Malfunction
NOTE:
Before you troubleshoot, review the general troubleshooting information.
Troubleshoot any PGM-FI system DTCs first.
This DTC is stored by communication failure between the F-CAN line and the adaptive damper control unit. When DTC U0029-00 is indicated, the F-CAN line has already returned to normal. Check for loose terminals and poor connections in the connectors. If the connectors are OK, clear the DTC and following this troubleshooting.

DTC Description
DTC
Freeze Frame
U0029-00 F-CAN Bus-Off Malfunction
    

1.
CAN gateway system DTC check:

CAN gateway system DTC check
?1.
Check for CAN gateway system DTCs with the HDS.
DTC Description
DTC
   

Are any DTCs indicated?

     
YES
     
     
     
     
NO
     
     
     
Go to step 2.
2.
F-CAN circuit communication check (Receiving control unit):

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.

  

Does the CAN gateway detect the adaptive damper control unit Bus channels B?

     
Adaptive damper control unit (Bus B) is Not Available
     
     
     
Go to step 3.
     
Adaptive damper control unit is Available for Bus B
     
     
     
Check for loose terminals and poor connections in the adaptive damper control unit connector. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting. If they are OK, replace the adaptive damper control unit.?
3.
Open wire check (F-CAN B_H, F-CAN B_L lines):

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.
Adaptive damper control unit 24P connector
CAN gateway 16P connector

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Adaptive damper control unit 24P connector: disconnected
 
CAN gateway 16P connector: disconnected
Test point 1
Adaptive damper control unit 24P connector No. 19
Test point 2
CAN gateway 16P connector (female terminals) No. 6:

Test point 1
Adaptive damper control unit 24P connector No. 20
Test point 2
CAN gateway 16P connector (female terminals) No. 14:


Is there 1.0 ? or less?

     
YES
     
     
     
The F-CAN B_H wire and the F-CAN B_L wire are OK. Check for any authorized service information related to the DTCs or symptoms you are troubleshooting or substitute a known-good adaptive damper control unit, then recheck. If the symptom/indication goes away with a known-good adaptive damper control unit, replace the original adaptive damper control unit.?
     
NO
     
     
     
Repair an open in the F-CAN B_H and/or F-CAN B_L wire between the adaptive damper control unit and the CAN gateway.?