AI Damage2018 Cadillac CT6 Plug-IN Hybrid reliability: common problems
Owners of the 2018 Cadillac CT6 Plug-IN Hybrid filed 3 complaints with NHTSA, most often about electrical system and engine. The maker issued 53 service bulletins for this year. Details by component below, with sources.
Key figures
- Owner complaints
- 3
- Technical service bulletins (TSB)
- 53
What fails most often
- 1 Electrical system 33% of all complaints
- 2 Engine 33% of all complaints
- 3 Steering 33% of all complaints
- 4 Powertrain 33% of all complaints
- 5 Electronic stability control 33% of all complaints
- Electrical system: 1 complaints (33% of all); manufacturer bulletins for this component: 21.
- Engine: 1 complaints (33% of all); manufacturer bulletins for this component: 2.
- Steering: 1 complaints (33% of all); manufacturer bulletins for this component: 2.
- Powertrain: 1 complaints (33% of all); manufacturer bulletins for this component: 1.
- Electronic stability control: 1 complaints (33% of all).
Symptoms owners describe
How many of the 3 NHTSA complaints mention each symptom (automatic count from complaint text; one complaint can mention several).
Components owners complain about
| Component | Owner complaints | involving a crash | Technical service bulletins (TSB) |
|---|---|---|---|
| Electrical system | 1 | 0 | 21 |
| Engine | 1 | 0 | 2 |
| Steering | 1 | 0 | 2 |
| Powertrain | 1 | 0 | 1 |
| Electronic stability control | 1 | 0 | 0 |
| Equipment | 0 | 0 | 16 |
| Wheels | 0 | 0 | 3 |
| Fuel/propulsion system | 0 | 0 | 2 |
| Backover prevention | 0 | 0 | 1 |
| Communication | 0 | 0 | 1 |
| Forward collision avoidance | 0 | 0 | 1 |
| Lane departure | 0 | 0 | 1 |
| Vehicle speed control | 0 | 0 | 1 |
| Other | 0 | 0 | 11 |
What owners report
Short excerpts of NHTSA complaints in the original wording. These are owner statements not verified by NHTSA; personal data removed.
The car would just stop in the middle of the ride or jerking as I drive it. I have been on the highway when it has stalled before as I drive. I have had these problems since I purchased the car in 2018
Vehicle check engine, power limited, and electric motor overheat warning lights come on. The combustion engine will not start, and battery power availability goes to zero.
Right after purchase, the nav screen kept flickering, causing a distracted driver situation and a hazard. The dealer did everything they could per gm guidelines, but even after the 1st service visit, the car would shut down in drive mode, as the vehicle was in motion.
When owners complained
NHTSA complaints by filing year. The peak shows at what age the problems show up most.
Comparison
By complaint count this model year ranks 15,523 of 32,257 model years in the NHTSA data (top 48% most complained about).
On average one model year of the CT6 Plug-IN Hybrid has 6 complaints (2 years in the data). This year has 3, below average.
What to check before buying
- Electrical system. Scan all modules, test the battery and alternator, inspect connectors near the impact zone.
- Engine. Cold start, unusual noises, oil leaks and engine codes.
- Steering. Steering play, power assist, rack and tie rods after a wheel impact.
- Powertrain. Shift quality under load, harsh shifts, transmission codes, CV joints.
Manufacturer service bulletins
Bulletin titles as filed with NHTSA.
- This PI provides Diagnostics tips on how the LIN bus works and how to diagnosis it
- This preliminary information advises a dealer on how to email GDS2 session logs into Technical Assistance
- PI to help diagnose A/C concern
- This preliminary information communicates information about how to determine if a wheel and tires size…
- This Preliminary information communicates the steps on how to save a GDS2 Session Log and upload to a…
This Preliminary information communicates the steps on how to save a GDS2 Session Log and upload to a Technical Assistance Case in CX Connect.
- This service bulletin provides information on Tire Sidewall Irregularities
- This service bulletin provides information on replacing the intake manifold when the engine is replaced…
This service bulletin provides information on replacing the intake manifold when the engine is replaced after severe internal engine damage.
- This Preliminary Information communication provides information to the technician about vehicles that have…
This Preliminary Information communication provides information to the technician about vehicles that have had multiple repair attempts that are being performed on customer’s vehicles that exhibit vibration conditions…
- This Warranty Administration service bulletin provides Lithium-Ion battery Exchange Process and…
This Warranty Administration service bulletin provides Lithium-Ion battery Exchange Process and Transaction Submission information.
- New Vehicle Monitoring Programs Section in IVH
- This Preliminary Information communication provides information to the technician about vehicles that have…
This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may…
- This Preliminary Information communication provides information to the technician about vehicles that have…
This Preliminary Information communication provides information to the technician about vehicles that have an intermittent no crank, no start, or start stall concern with the security light coming on. Technician may…
NHTSA lists 53 bulletins for this year; the 12 newest are shown here.
Other years of this model
Questions and answers
What are the most common problems with the 2018 Cadillac CT6 Plug-IN Hybrid?
Owner complaints to NHTSA most often mention: electrical system, engine, steering. Total complaints: 3. The most frequent symptoms in complaint texts: jerking, harsh shifts (33%), won't start (33%), overheating, coolant loss (33%).
How many service bulletins (TSB) were issued for the 2018 Cadillac CT6 Plug-IN Hybrid?
NHTSA lists 53 manufacturer service bulletins for this year. A bulletin tells dealers how to diagnose or fix a known issue; it is not a recall.
Should I buy a 2018 Cadillac CT6 Plug-IN Hybrid from a US auction?
Owner complaints describe defects, not crash damage. Before bidding, check the components listed above and review the lot photos: VinWind builds a report of visible and hidden damage by VIN.
Other 2018 models
Read also
Sources: public NHTSA data (USA): service bulletins and owner complaints; YouTube: links to videos credited to their authors. Complaints are owner statements not verified by NHTSA, and describe defects rather than crash damage. Data updated 2026-11-06.