DTC Troubleshooting: B1038
DTC B1038: IMMOBILIZER F-CAN Authentication ID Not Received
NOTE:
If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A.
If keyless access power control unit DTC U0073 is stored, troubleshoot DTC U0073 first.

DTC Description
DTC
B1038 IMMOBILIZER F-CAN Authentication ID Not Received
  

1.
Problem verification:

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


?2.
Turn the vehicle to the OFF (LOCK) mode and then the ON mode.

?3.
Check for DTCs with the HDS.
DTC Description
DTC
B1038 IMMOBILIZER F-CAN Authentication ID Not Received
  

Is DTC B1038 indicated?

     
YES: with CAN gateway
     
     
     
Go to step 2.
     
YES: without CAN gateway
     
     
     
Go to step 3.
     
NO
     
     
     
Intermittent failure, the system is OK at this time. Check for loose or poor connections.?
2.
CAN gateway system DTC check:

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
  
U0047-00 CAN Gateway F-CAN ch B Bus Off
  
U3000-49 CAN Gateway Internal Failure
  

Is DTC U0029-00, U0047-00, and/or U3000-49 indicated?

     
YES
     
     
     
     
NO
     
     
     
Go to step 3.
3.
Gauge control module DTC check:

Gauge control module DTC check
?1.
Check for gauge control module DTCs with the HDS.
DTC Description
DTC
U0122 Gauge control module lost communication with VSA modulator-control unit
  

Is DTC U0122 indicated?

     
YES
     
     
     
     
NO: with CAN gateway
     
     
     
Go to step 4.
     
NO: without CAN gateway
     
     
     
Go to step 9.
4.
F-CAN circuit communication check:

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.

  

Does the body control module detect the CAN gateway Bus channels A?

     
Bus A is Not Available
     
     
     
Go to step 5.
     
Bus A is Available
     
     
     
Go to step 6.
5.
Open wire check (F-CAN A lines):

Open wire check (F-CAN A lines)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connectors.
CAN gateway 12P connector
Body control module connector B (36P)

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
CAN gateway 12P connector: disconnected
Body control module connector B (36P): disconnected
Test point 1
CAN gateway 12P connector (female terminals) No. 3:
Test point 2
Body control module connector B (36P) No. 22

Test point 1
CAN gateway 12P connector (female terminals) No. 9:
Test point 2
Body control module connector B (36P) No. 23


Is there continuity?

     
YES
     
     
     
The F-CAN A_H and F-CAN A_L wires are OK. Replace the body control module.?
     
NO
     
     
     
Repair an open in F-CAN A_H or F-CAN A_L wire.?
6.
F-CAN circuit communication check (Transmitting control unit):

F-CAN circuit communication check (Transmitting control unit)
?1.
Select the FUNCTION TEST in the CAN gateway with the HDS, then select the F-CAN Bus Connected Unit Check.

  

?2.
According to the detected DTC on the following table, make sure that the transmitting control unit detects the CAN gateway Bus channels normally.
DTC
Transmitting control unit
Detected CAN gateway Bus channels at normal
B1038
VSA modulator-control unit
A, B

Is it detected normally?

     
Detected normal
     
     
     
Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the transmitting control unit and the CAN gateway.?
     
U0122: VSA modulator-control unit is Not Available for Bus A
     
     
     
Go to step 7.
     
U0122: VSA modulator-control unit is Not Available for Bus B
     
     
     
Go to step 8.
7.
Open wire check (F-CAN A lines):

Open wire check (F-CAN A lines)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
According to the detected DTC on the following table, disconnect the transmitting control unit connectors.
DTC
Connector
-
CAN gateway 12P connector
B1038
VSA modulator-control unit 46P connector

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
CAN gateway 12P connector: disconnected
Transmitting control unit connector for indicated DTCs: disconnected

DTC
Circuit name
Test point 1 (Receiving control unit)
Test point 2 (Transmitting control unit)
Connector
Terminal
Connector
Terminal
B1038
F-CAN A_H
CAN gateway 12P connector (female terminals):
No. 3
VSA modulator-control unit 46P connector
No. 40
F-CAN A_L
No. 9
No. 28


Is there continuity?

     
YES
     
     
     
The F-CAN A_H wire and the F-CAN A_L wire are OK.
Refer to the DTC shown on the display, replace the control unit based on the instructions (see table).?
DTC
Operation for transmitting control unit
B1038
VSA modulator-control unit
     
NO
     
     
     
Repair an open in F-CAN A_H or F-CAN A_L wire.?
8.
Open wire check (F-CAN B lines):

Open wire check (F-CAN B lines)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
According to the detected DTC on the following table, disconnect the transmitting control unit connectors.
DTC
Connector
-
CAN gateway 12P connector
B1038
VSA modulator-control unit 46P connector

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
CAN gateway 12P connector: disconnected
Transmitting control unit connector for indicated DTCs: disconnected

DTC
Circuit name
Test point 1 (Receiving control unit)
Test point 2 (Transmitting control unit)
Connector
Terminal
Connector
Terminal
B1038
F-CAN B_H
CAN gateway 12P connector (female terminals):
No. 12
VSA modulator-control unit 46P connector
No. 46
F-CAN B_L
No. 5
No. 34


Is there continuity?

     
YES
     
     
     
The F-CAN B_H wire and the F-CAN B_L wire are OK.
Refer to the DTC shown on the display, replace the control unit based on the instructions (see table).?
DTC
Operation for transmitting control unit
B1038
VSA modulator-control unit
     
NO
     
     
     
Repair an open in F-CAN B_H or F-CAN B_L wire.?
9.
Open wire check (F-CAN lines):

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

?2.
Disconnect the following connectors.
Body control module connector B (36P)
VSA modulator-control unit 46P connector

?3.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
Body control module connector B (36P): disconnected
VSA modulator-control unit 46P connector: disconnected
Test point 1
Body control module connector B (36P) No. 22
Test point 2
VSA modulator-control unit 46P connector No. 40


Is there continuity?

     
YES
     
     
     
     
NO
     
     
     
An open or poor connection in the F-CAN_H and/or F-CAN_L wire.?