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. (See DTC DISPLAY.) • 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. (See ON-BOARD DIAGNOSIS [DSC/RSC].) • 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. (See DSC/RSC HU/CM REMOVAL/INSTALLATION [L.H.D.].) (See DSC/RSC HU/CM REMOVAL/INSTALLATION [R.H.D.].)
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. (See ON-BOARD DIAGNOSIS [DSC/RSC].)
No | DTC troubleshooting completed.