P2CF0

Auxiliary Thermostat A Stuck Closed

Severity

🔴 High

Can you drive?

Do not drive — repair immediately

Approx. repair cost

$17–56 (est.)

Symptoms

Engine overheating
Reduced cooling system efficiency
Unstable engine operation at idle
Increased fuel consumption
Overheat warning light comes on

Causes

Mechanical jamming of the thermostat
Low quality coolant
Corrosion inside the thermostat
Problems with the electrical part of the thermostat control
Cooling system contamination

How to Fix

Check the level and condition of the coolant
Diagnose thermostat operation
Replace a faulty thermostat
Flush the cooling system
Check electrical connections of thermostat control

Related codes

P0128 P2181 P2183