P0128 on JEEP CHEROKEE — Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)

Q: "What does P0128 mean on a JEEP CHEROKEE?"

"P0128 indicates: Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature). This is a fuel and air metering code. 4 JEEP CHEROKEE owners have reported this to NHTSA."

Q: "What are the most common causes of P0128 on JEEP CHEROKEE?"

"Based on 4 NHTSA reports, the most commonly cited components are: Engine, Unknown Or Other,Engine, Power Train,Electrical System,Air Bags. These percentages are based on the component field in owner complaints."

Q: "Is P0128 a safety concern on JEEP CHEROKEE?"

"Of 4 NHTSA reports for P0128 on JEEP CHEROKEE, 1 involved a crash. Always consult a qualified mechanic for any diagnostic trouble code."

Q: "What should I do if my JEEP CHEROKEE shows P0128?"

"1) Check for recalls on your VIN at nhtsa.gov/recalls. 2) Get a professional diagnosis — a code alone doesn't identify the exact failed part. 3) Get 2-3 repair estimates to compare."

What P0128 Means on Your JEEP CHEROKEE

P0128 is a diagnostic trouble code indicating: Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature). This code relates to the fuel and air metering system. The vehicle's computer detected a condition outside normal operating parameters and stored this code.

4 JEEP CHEROKEE owners have reported this issue to NHTSA across model years 2016-2017. Most reports come from the 2016, 2017 model years. The most commonly reported component is Engine (50.0% of reports).

Real JEEP CHEROKEE Owner Reports

Source: NHTSA Complaints Database

"Cei p0128 coolant temperature too cold. no overheating issues, temps have remained consistently. came on while driving. thermostat needs replacing in only 4 years from purchase. temps have only been hovering around freezing."

— 2016 JEEP CHEROKEE owner · ENGINE · Filed 11/18/2019

"Cei p0128 coolant temperature too cold. having to replace thermostat on a car only 3 years old. temps have not been below freezing & didn't have this issue last winter. thermostat is stuck open so gas consumption has increased & heat has decreased."

— 2016 JEEP CHEROKEE owner · ENGINE · Filed 11/13/2019

"Engine and car was not warming up with remote start. Finally check engine light comes on. Code P0128 thermostat. Repaired 1/28/2021 @ 85762 miles. All antifreeze replaced. $600+ repair. 2/1/2022 same observed failure of engine to warm up during remote starts."

— 2017 JEEP CHEROKEE owner · UNKNOWN OR OTHER,ENGINE · Filed 02/06/2022

"'shifter bezel and wiring requires replacement according to eide chrysler service techs 'shift module not functioning ' replaced by eide chrysler twice 'vehicle randomly swaps between r/n/d while driving 'vehicle has difficult time starting 'check engine light ' code p0128 ' coolant temperature"

— 2017 JEEP CHEROKEE owner · POWER TRAIN,ELECTRICAL SYSTEM,AIR BAGS · Filed 03/14/2020 ⚠️ Crash reported

All reports filed by vehicle owners directly with the U.S. Department of Transportation.

📊 Complaint Trend by Model Year

2

'16

2

'17

Common Causes on JEEP CHEROKEE

Based on NHTSA complaint component analysis for this vehicle.

ENGINE 50%

UNKNOWN or OTHER,ENGINE 25%

POWER TRAIN,ELECTRICAL SYSTEM,AIR BAGS 25%

What To Do Next

1
Check for recalls on YOUR VIN
Go to nhtsa.gov/recalls and enter your VIN. If your vehicle is covered, repairs are free.
2
Get a proper diagnosis
A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50–$150) pinpoints the root cause before you spend money on parts.
3
Compare repair quotes
Get 2–3 quotes. Dealer vs. independent shop prices often differ 30–50% for the same repair.

Frequently Asked Questions

What does P0128 mean on a JEEP CHEROKEE? ▾

P0128 indicates: Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature). This is a fuel and air metering code. 4 JEEP CHEROKEE owners have reported this to NHTSA.

What are the most common causes of P0128 on JEEP CHEROKEE? ▾

Based on 4 NHTSA reports, the most commonly cited components are: Engine, Unknown Or Other,Engine, Power Train,Electrical System,Air Bags. These percentages are based on the component field in owner complaints.

Is P0128 a safety concern on JEEP CHEROKEE? ▾

Of 4 NHTSA reports for P0128 on JEEP CHEROKEE, 1 involved a crash. Always consult a qualified mechanic for any diagnostic trouble code.

What should I do if my JEEP CHEROKEE shows P0128? ▾

1) Check for recalls on your VIN at nhtsa.gov/recalls. 2) Get a professional diagnosis — a code alone doesn't identify the exact failed part. 3) Get 2-3 repair estimates to compare.