General Motors has released a Service Update to address an issue related to the transmission wiring harness on certain 2017 and 2018 model year Cadillac CT6 PHEV luxury sedans.
The problem: in affected vehicles, the transmission wiring harness may have a faulty thermistor crimp.
The hazards: GM did not say what problems the faulty thermistor crimp may cause. A thermistor is a temperature-sensitive type of resistor that exhibits a change in electrical resistance when exposed to varying ambient temperatures. While GM did not say what problems this may lead to, it;s likely the problem could lead to further transmission issues if not addressed.
The fix: GM dealers will be instructed to replace the transmission wiring harness in affected vehicles. These repairs will be performed at no cost to the vehicle owner. This service update involves vehicles in dealer inventory and customer-owned vehicles that may return to the dealership for any reason in the future.
Affected components: transmission wiring harness, transmission wiring harness thermistor, four-mode hybrid transmission.
- 2017 Cadillac CT6 PHEV
- 2018 Cadillac CT6 PHEV
Number of affected vehicles: only 551 vehicles are involved in this recall campaign that will require parts to be replaced.
Owners should: GM will notify owners of affected vehicles and instruct them to make an appointment with their dealer. Owners of affected vehicles can also reach out to Cadillac directly using the contact information included below. This service update was first issued in July 2021. To reiterate, this service update applies to Cadillac CT6 PHEV models only and not vehicles with traditional, non-hybrid internal combustion engines.
- GM Service Update Number:
- Cadillac Customer Service: 1-800-333-4223