DTC C1783: Speed Signal Communication Error [03/2019 - ]: Procedure

WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2024 Lexus RC F, 2023 Lexus RC F, 2022 Lexus RC F, 2021 Lexus RC F, and 2020 Lexus RC F. However, it is still accessible from the selected car via links, so may be relevant.

CHECK FOR DTC (CAN COMMUNICATION SYSTEM)

Check for DTCs.

Refer to DTC CHECK / CLEAR [08/2016 - 01/2023] , or refer to DTC CHECK / CLEAR [01/2023 - ]

Chassis > Air suspension > Trouble Codes

Result

Result	Proceed to
CAN DTCs are not output	A
CAN DTCs are output	B

Result:

GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITH TROUBLESHOOTING). Refer to HOW TO PROCEED WITH TROUBLESHOOTING [03/2019 - 01/2023] , or refer to HOW TO PROCEED WITH TROUBLESHOOTING [01/2023 - ]

Result:

See step 2

CHECK FOR DTC (VEHICLE STABILITY CONTROL SYSTEM)

Check if DTC C1783 and a vehicle stability control system speed sensor malfunction DTC are output.

Refer to DTC CHECK / CLEAR [03/2019 - 01/2023] , or refer to DTC CHECK / CLEAR [01/2023 - ]

Chassis > Brake > Trouble Codes

Result

Result	Proceed to
DTC is not output	A
DTC is output	B

Result:

REPLACE ABSORBER CONTROL ECU. Refer to REMOVAL [08/2016 - 01/2023] , or refer to REMOVAL [01/2023 - ]

Result:

GO TO VEHICLE STABILITY CONTROL SYSTEM (DIAGNOSTIC TROUBLE CODE CHART). Refer to DIAGNOSTIC TROUBLE CODE CHART [03/2019 - 01/2023] , or refer to DIAGNOSTIC TROUBLE CODE CHART [01/2023 - ]