2021 Jeep Grand Cherokee: Will not start when below freezing
Common wear/failure (not a recall)
Symptoms
Owners of the 2021 Grand Cherokee report: will not start when below freezing. CarComplaints.com lists 2 owner complaints, average mileage 14,900 miles.
NHTSA has 143 owner complaints for the 2021 Grand Cherokee in this area. Examples:
- NHTSA complaint ODI #11770597 (filed 10/12/2026): “Vehicle: 2021 jeep grand cherokee overland, 3.6l v6 incident date: [xxx] location: [xxx] safety complaint: on [xxx], while driving my 2021 jeep grand cherokee overland on [xxx], the vehicle suddenly lost accelerator response while traveling on the highway. …”
- NHTSA complaint ODI #11759412 (filed 08/25/2026): “Final drive control module, transfercase control module went out. causing “service 4wd” message check-engine/mil light 4wd system becoming unavailable trouble codes related to the drivetrain control module intermittent 4wd problems speed issues…”
Likely causes
Sources do not establish a single root cause; diagnosis is needed. Owner-reported fixes are listed below.
Fix, in plain English
Most common owner-reported solutions on CarComplaints.com: none clearly reported. Check for open recalls and extended warranty coverage with a dealer before paying out of pocket.
DIY difficulty: Moderate
Finding and splicing chewed wiring is doable with a multimeter and patience but can be time-consuming; harness replacement is pro work. (Our assessment.)
Cost
No sourced cost range: get a written quote after diagnosis.
Typical parts (search links, no affiliate codes)
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