Cadillac has issued a service update to address an issue affecting the engine control modules in certain units of the 2021 Cadillac CT4 luxury sedan.
The problem: some units of the 2021 Cadillac CT4 with the turbocharged 2.0L I4 engine (production code LSY) have an engine control module (ECM) that may not properly diagnose, may not set a Diagnostic Trouble Code (DTC), or may not illuminate the malfunction indicator light (check engine light) if certain issues with the vehicle’s catalytic converter were to occur.
The hazards: if a fault occurs with the catalytic converter and the ECM does not diagnose or set a code, the vehicle owner may not be made aware of said fault.
The fix: an update for the ECM will be made over-the-air (OTA). This procedure may be performed remotely by the customer. Alternatively, customers may take their 2021 Cadillac CT4 to a preferred Cadillac dealer to have the procedure performed by a technician.
Affected vehicles: 2021 Cadillac CT4
Number of affected vehicles: Cadillac did not indicate how many units of the 2021 Cadillac CT4 may be affected by this condition.
Affected components: engine control module (ECM)
Next steps: owners of affected vehicles can reach out to Cadillac directly if there are any questions or concerns they wish to address using the contact information below. It’s important to note that this is a service update, not a recall, meaning that it will expire at the end of the vehicle’s New Vehicle Limited Warranty Period.
Contacts:
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