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.
Affected vehicles:
- 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.
Contacts:
- GM Service Update Number:
- Cadillac Customer Service: 1-800-333-4223
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Comments
Why bother with the fix?
GM clearly never wanted to sell a good car like the CT6. They prefer making cheap front drive crossovers and pickup trucks.
I always liked the CT6 it had a great road presence, very sharp car. But because of lack of vision, oh and let’s not forget the fiasco known as the Blackwing engine this would have been a legendary car. But no let’s sell rebadged Chevy Equinox and put in crap interiors, and call them Cadillacs, similar to the Cimmaron fiasco. If it wasn’t for Escalade Cadillac wouldn’t be around it is the only product that has a proper investment in it and that is why people buy it, even though it is a Chevy Suburban with fancier bells and whistles. The new Blackwing series cars will be great but everything else is a Joke. And Cadilac thinks electric will save them, it won’t the cars will just sit Cadillac will be gone by the start of the next decade
Ok
I have a black 2017 Cadillac CT6, Premium AWD and let me say, for the record, this car is absolutely amazing. I would describe it as transcendent. The handling, maneuvering, power, and sheer style and class is simply; breathtaking. I have the 3.6 liter V6 engine and this baby has some power. I’ve hit 135mph in this car and it’s so smooth and I could have had an open glass of champagne sitting on the center console and it wouldn’t slosh over the side. The interior is all black with leather seats a sunroof and moon roof it’s sleek, simplistic, and sexy as all hell. It takes regular 89 octane gas so you save at the pump and the trunk is so spacious it allowed me to add a 15in Kicker Subwoofer with amp and I was able to upgrade the stock Bose speaker system to all JBL speakers so when it flies down the highway the beat is knocking! This car gathers onlookers and compliments everywhere I go. Cadillac is bad as all hell and they definitely will be around in ten years… what I want and need next is the Cadillac Escala! A Concept car that is just ridiculous. Cadillac needs to get on with this Escala but I can confidently say I am a Cadillac man for life. Can’t drive and won’t drive or own anything other than Cadillac.
Cadillac is simply iconic. A symbol for class, style and sophistication that will live on through the ages. Keep on keeping on.
You are delusional. Quit drinking and smoking whatever you are smoking and don’t make ridiculous posts when high again. For what it is worth, my Pontiac hits 135 on interstate on-ramps(1/3 the cost of the Ct6), you shouldn’t be drinking in a car, there will be no escala, and high tech cars can’t grow or go with no microchip. So gm bet the farm on everything they cannot deliver!
I love our 2018 CT6 2.0E plug-in also. It is one car I have kept more than 18 months!
Anyone have a transmission wiring harness issue on a 2017 cadillac ct6 tgat is NOT a PHEV? Just spent $1200 to replace mine because check engine light went on.
Yes I’m having the same exact issue in my 2017. I had it flushed and it’s still the same.
I drive a non PHEV Cadillac CT6. Love the car but there is clearly a transmission problem. It jerks when it downshifts and from rest to 1st gear. It’s like Preakness leaving the gate at the Kentucky Derby. I’m afraid it’s going to cause unintentional harm.
The fluid needs to be changed. Have the dealership flush it and replace e with new.
I did and it didn’t work