p0128
Moderate
Dodge · SUVs
Coolant Thermostat (Coolant Temp Below Thermostat Regulating Temp)
Quick Answer
Error code P0128 on your Dodge SUVs means: Coolant Thermostat (Coolant Temp Below Thermostat Regulating Temp). This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Check coolant level and top off if low
2
Monitor coolant temperature with scanner
3
Verify coolant temperature sensor accuracy
4
Test thermostat operation
5
Replace thermostat if faulty
Pro Tip
This fix requires some technical knowledge. If you're unsure about any step, consider contacting support or a qualified technician.
Parts You May Need
Thermostat
Coolant
Water pump seal
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