p0128
Moderate
Porsche · SUVs
Coolant Thermostat (Coolant Temp Malfunction)
Quick Answer
Error code P0128 on your Porsche SUVs means: Coolant Thermostat (Coolant Temp Malfunction). 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 needed
2
Monitor coolant temperature with scanner
3
Feel radiator hose for temperature change
4
Test thermostat in hot water
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 assembly
Coolant
Coolant temperature sensor
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