DTC Troubleshooting: U0122-00
DTC U0122-00: Lost Communication With The VSA Modulator-Control Unit
NOTE: Before you troubleshoot, review the general troubleshooting information.

DTC Description
DTC
Freeze Frame
U0122-00 Lost Communication With The VSA Modulator-Control Unit
    

1.
Problem verification:

Problem verification
?1.
Turn the vehicle to the ON mode.

?2.
Clear the DTC with the HDS.


?3.
Turn the vehicle to the OFF (LOCK) mode.

?4.
Turn the vehicle to the ON mode, then wait for at least 5 seconds.

?5.
Check for DTCs with the HDS.
DTC Description
DTC
Freeze Frame
U0122-00 Lost Communication With The VSA Modulator-Control Unit
    

Is DTC U0122-00 indicated?

     
YES
     
     
     
The failure is duplicated. Go to step 2.
     
NO
     
     
     
Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting. 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.?
2.
Open wire check (F-CAN_L, F-CAN_H lines):

Open wire check (F-CAN_L, F-CAN_H lines)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connectors.
Multipurpose camera unit 20P connector
VSA modulator-control unit 38P connector

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Multipurpose camera unit 20P connector: disconnected
 
VSA modulator-control unit 38P connector: disconnected
Test point 1
Multipurpose camera unit 20P connector No. 13
Test point 2
VSA modulator-control unit 38P connector No. 26


Is there continuity?

     
YES
     
     
     
The F-CAN_L, F-CAN_H wires are OK. Go to step 3.
     
NO
     
     
     
Repair an open in the wire between the multipurpose camera unit and VSA modulator-control unit.?
3.
VSA modulator-control unit check (substitution):

VSA modulator-control unit check (substitution)
?1.
Reconnect the following connectors.
Multipurpose camera unit 20P connector

?2.
Substitute a known-good VSA modulator-control unit.

?3.
Clear the DTC with the HDS.


?4.
Turn the vehicle to the OFF (LOCK) mode.

?5.
Turn the vehicle to the ON mode, then wait for at least 5 seconds.

?6.
Check for DTCs with the HDS.
DTC Description
DTC
Freeze Frame
U0122-00 Lost Communication With The VSA Modulator-Control Unit
    

Is DTC U0122-00 indicated?

     
YES
     
     
     
Check for loose terminals and poor connections in the multipurpose camera unit 20P connector. If they are OK, replace the multipurpose camera unit.?
     
NO