DTC U1901 [DSC/RSC]


id0402b3811700

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

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT COMBINED SENSOR SIGNAL (CAN2 LINE) FOR OPEN CIRCUIT
•  Disconnect the DSC/RSC HU/CM connectors.
•  Disconnect the combined sensor connectors.
•  Inspect for continuity between the DSC/RSC HU/CM connectors (vehicle harness-side) and the following combined sensor connector terminals (vehicle harness-side):
―  Combined sensor (CAN2_L): M—C
―  Combined sensor (CAN2_H): P—D
•  Is there continuity?
Yes
Go to the next step.
No
Repair or replace the wiring harness, then go to Step 4.
2
INSPECT COMBINED SENSOR SIGNAL (CAN2 LINE) FOR SHORT CIRCUIT
•  Inspect for continuity between the following DSC/RSC HU/CM connector terminals (vehicle harness-side) and body ground:
―  Combined sensor (CAN2_L): M
―  Combined sensor (CAN2_H): P
•  Is there continuity?
Yes
Repair or replace the wiring harness, then go to Step 4.
No
Go to the next step.
3
INSPECT THE COMBINED SENSOR
•  Reconnect all disconnected connectors.
Inspect the combined sensor.
•  Is the combined sensor normal?
Yes
Go to the next step.
No
Replace the combined sensor, then 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.