DTC U0401-81: Invalid Data Received from ECM/PCM "A" Invalid Serial Data Received [01/2019 - 09/2022]: Procedure

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CHECK FOR DTCs

Clear the DTCs.
Powertrain > Radar Cruise 2 > Clear DTCs
Make sure that the DTC detection conditions are met.
HINT:

If the detection conditions are not met, the system cannot detect the malfunction.

Check for DTCs.

Powertrain > Radar Cruise 2 > Trouble Codes

Result

Result	Proceed to
DTC U0401-81 is not output	A
DTC U0401-81 is output	B

Result:

A

USE SIMULATION METHOD TO CHECK. Refer to HOW TO PROCEED WITH TROUBLESHOOTING [06/2018 - ]

Result:

B

REPLACE ECM. Refer to COMPONENTS [01/2019 - 11/2022]