DTC Troubleshooting: B2638
DTC B2638: Front Left Sensor Bus Failure
DTC Description
DTC
B2638 Front left sensor bus failure
  

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A.

1.
Problem verification:

Problem verification
?1.
Clear the DTCs with the HDS.


?2.
Press the engine start/stop button to select the OFF mode and then the ON mode.

?3.
Turn the parking and back-up sensor switch to ON.

?4.
Wait for at least 5 seconds.

?5.
Check for DTCs with the HDS.
DTC Description
DTC
B2638 Front left sensor bus failure
  

Is DTC B2638 indicated?

     
YES
     
     
     
Go to step 2.
     
NO
     
     
     
Intermittent failure, the system is OK at this time. Check for loose or poor connections.?
2.
DTC check:

DTC check
?1.
Check for DTCs with the HDS.
DTC Description
DTC
B2638 Front left sensor bus failure
  
B2641 Front right sensor bus failure
  

Is DTC B2638 and/or B2641 indicated?

     
YES
     
     
     
Go to step 3.
     
YES
     
     
     
Go to step 6.
     
NO
     
     
     
Check for loose or poor connections. If OK, replace the parking and back-up sensor control unit.?
3.
Left front corner sensor check:

Left front corner sensor check
?1.
Swap the left front corner sensor and the right front corner sensor.

?2.
Clear the DTCs with the HDS.


?3.
Press the engine start/stop button to select the OFF mode and then the ON mode.

?4.
Turn the parking and back-up sensor switch to ON.

?5.
Wait for at least 5 seconds.

?6.
Check for DTCs with the HDS.
DTC Description
DTC
B2638 Front left sensor bus failure
  

Is DTC B2638 indicated?

     
YES
     
     
     
Go to step 4.
     
NO
     
     
     
4.
Shorted wire check (SOF SIDE L line to power):

Shorted wire check (SOF SIDE L line to power)
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Press the engine start/stop button to select the ON mode.

?4.
Measure the voltage between test points 1 and 2.
Test condition
ON mode
Left front corner sensor 6P connector: disconnected
Test circuit
SOF SIDE L
Test point 1
Left front corner sensor 6P connector No. 2 (PNK)
Test point 2
Body ground


Is there battery voltage?

     
YES
     
     
     
Repair a short to power in the SOF SIDE L wire between the left front corner sensor and the parking and back-up sensor control unit.?
     
NO
     
     
     
The SOF SIDE L wire is not shorted to power, go to step 5.
5.
Shorted wire check (SOF SIDE L line):

Shorted wire check (SOF SIDE L line)
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Check for continuity between test points 1 and 2.
Test condition
OFF mode
Left front corner sensor 6P connector: disconnected
Parking and back-up sensor control unit 24P connector: disconnected
Test circuit
SOF SIDE L
Test point 1
Left front corner sensor 6P connector No. 2 (PNK)
Test point 2
Body ground


Is there continuity?

     
YES
     
     
     
Repair a short to ground in SOF SIDE L wire between the left front corner sensor and the parking and back-up sensor control unit.?
     
NO
     
     
     
Repair an open or high resistance in SOF SIDE L wire between the left front corner sensor and the parking and back-up sensor control unit.?
6.
Open wire check (BOF SIDE L, E1 SIDE L lines):

Open wire check (BOF SIDE L, E1 SIDE L lines)
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connectors.

?3.
Check for continuity between test points 1 and 2.
Test condition
OFF mode
Parking and back-up sensor control unit 24P connector: disconnected
Left front corner sensor 6P connector: disconnected
Test circuit
BOF SIDE L
Test point 1
Parking and back-up sensor control unit 24P connector No. 2 (TAN)
Test point 2
Left front corner sensor 6P connector No. 6 (ORN)


Is there continuity?

     
YES
     
     
     
Repair an open or high resistance in E1 SIDE L wire between the parking and back-up sensor control unit and the left front corner sensor.?
     
NO
     
     
     
Repair an open or high resistance in BOF SIDE L wire between the parking and back-up sensor control unit and the left front corner sensor.?