DTC C1A31-08: Driver Monitor Camera Control System Bus Signal / Message Failure; DTC C1A31-87: Driver Monitor Camera Missing Message [10/2023 - ]: Procedure

WARNING: This page is about a different car, the 2024 Lexus LS 500h. However, it is still accessible from the selected car via links, so may be relevant.

CHECK HARNESS AND CONNECTOR (DRIVER MONITOR ECU ASSEMBLY - DRIVER MONITOR CAMERA)

Pre-procedure1

Disconnect the G222 driver monitor ECU assembly connector.
Disconnect the G177 driver monitor camera connector.
Procedure1

Measure the resistance according to the value(s) in the table below.

Standard Resistance

Tester Connection	Condition	Specified Condition
G222-1 (GND) - G177-1 (GND)	Always	Below 1 Ω
G222-2 (+B) - G177-2 (+B)	Always	Below 1 Ω
G222-3 (LVDS+) - G177-4 (LVDS+)	Always	Below 1 Ω
G222-4 (LVDS-) - G177-3 (LVDS-)	Always	Below 1 Ω
G222-1 (GND) - Body ground	Always	10 kΩ or higher
G222-2 (+B) - Body ground	Always	10 kΩ or higher
G222-3 (LVDS+) - Body ground	Always	10 kΩ or higher
G222-4 (LVDS-) - Body ground	Always	10 kΩ or higher
G222-5 (SGND) - Body ground	Always	10 kΩ or higher

Result

Proceed to
OK
NG

Post-procedure1

None

Result:

REPAIR OR REPLACE HARNESS OR CONNECTOR

Result:

See step 2

REPLACE DRIVER MONITOR CAMERA
HINT:

Refer to REMOVAL [10/2023 - ]

Result

Proceed to

NEXT

Result:

NEXT

See step 3

CLEAR DTC

Clear the DTCs.

Chassis > Driver Monitor Camera Control > Clear DTCs

Result

Proceed to
NEXT

Result:

See step 4

CHECK FOR DTC

Check for DTCs.

Chassis > Driver Monitor Camera Control > Trouble Codes

Result

Result	Proceed to
DTCs are not output	A
C1A31-08 or C1A31-87 is output	B

Result:

END (DRIVER MONITOR CAMERA IS DEFECTIVE)

Result:

REPLACE DRIVER MONITOR ECU ASSEMBLY. Refer to REMOVAL [10/2023 - ]