DTC U1901 [DSC/RSC]


id0402b3811700

DTC
U1901
SAS control module system (CAN2 line malfunction)
DETECTION CONDITION
•  The signal from the SAS control module is not within specification.
POSSIBLE CAUSE
•  SAS control module malfunction
•  Open or short circuit in the CAN2_L wiring harness between SAS control module terminal 2D and DSC/RSC HU/CM terminal M
•  Open or short circuit in the CAN2_H wiring harness between SAS control module terminal 2H and DSC/RSC HU/CM terminal P
•  DSC/RSC HU/CM malfunction
•  Poor connection at connectors (female terminal)

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT SAS CONTROL MODULE MALFUNCTION
•  Turn the ignition switch off.
•  Using the M-MDS, perform the DTC inspection for the SAS control module.
•  Are any DTCs detected?
Yes
Go to applicable DTC inspection.
(See DTC TABLE.)
No
Go to the next step.
2
INSPECT SAS CONTROL MODULE SIGNAL (CAN2 LINE) FOR OPEN CIRCUIT
•  Disconnect the DSC/RSC HU/CM connectors.
•  Disconnect the SAS control module connectors.
•  Inspect for continuity between the DSC/RSC HU/CM connectors (vehicle harness-side) and the following SAS control module connector terminals (vehicle harness-side):
―  SAS control module (CAN2_L): 2D—M
―  SAS control module (CAN2_H): 2H—P
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 4.
3
INSPECT SAS control module SIGNAL (CAN2 LINE) FOR SHORT CIRCUIT
•  Inspect for continuity between the following DSC/RSC HU/CM connector terminals (vehicle harness-side) and body ground:
―  DSC/RSC HU/CM (CAN2_L): M
―  DSC/RSC HU/CM (CAN2_H): P
•  Is there continuity?
Yes
Repair or replace the wiring harness, then go to Step 4.
No
Go to the next step.
4
VERIFY THAT THE SAME DTC IS NOT PRESENT
•  Clear the DTCs from the memory.
•  Are the same DTCs present?
Yes
Repeat the inspection from Step 1.
If the malfunction recurs, replace the DSC/RSC HU/CM, then go to the next step.
No
Go to the next step.
5
VERIFY THAT NO OTHER DTCS ARE PRESENT
•  Are any other DTCs output?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.