p0128
Moderate
Citroen · Sedans & Hatchbacks
Coolant Thermostat (Coolant Temp not reaching normal operating temp)
Quick Answer
Error code P0128 on your Citroen Sedans & Hatchbacks means: Coolant Thermostat (Coolant Temp not reaching normal operating temp). This is usually fixable — see the step-by-step guide below.
Affected Models
Likely Causes
How to Fix It
1
Check coolant level when engine is cold
2
Verify engine reaches normal operating temperature
3
Monitor coolant temperature with scanner
4
Check cooling fan operation
5
Replace thermostat if stuck
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 temperature sensor
Engine coolant
Thermostat housing gasket
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