D
p0128
Moderate
DS Automobiles · Sedans & SUVs
Coolant Thermostat (Coolant Temp not reaching normal operating temp)
Quick Answer
Error code P0128 on your DS Automobiles Sedans & SUVs means: Coolant Thermostat (Coolant Temp not reaching normal operating temp). This is usually fixable — see the step-by-step guide below.
Affected Models
Applies to all models
AA-EBCC-ED
Likely Causes
  1. Thermostat stuck open
  2. Low coolant level
  3. Coolant temperature sensor failure
  4. Engine cooling fan always on
  5. Water pump failure
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
Related Error Codes
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