P0126 Fault Code

Insufficient Coolant Temperature for Stable Operation

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0126 fault code indicates that the engine control module (ECM) has detected that the temperature of the coolant is lower than the expected range for stable engine operation. This can lead to suboptimal engine performance and increased emissions.

What are the symptoms of the P0126 code?

• Engine may run rough or have poor acceleration
• Check Engine light is illuminated
• Decreased fuel efficiency due to improper engine temperature
• Overheating engine if the thermostat is stuck closed
• Unusual engine noises due to excessive cold running

What causes the P0126 code?

• Low coolant levels in the system
• Faulty thermostat that fails to close
• Weak or defective coolant temperature sensor
• Radiator or engine block issues causing improper heat exchange
• Air pockets in the cooling system preventing accurate temperature readings

How to fix P0126?

• Inspect and replenish coolant levels as needed
• Replace the faulty thermostat to ensure proper coolant flow
• Test and replace coolant temperature sensor if it is malfunctioning
• Bleed the cooling system to remove any air pockets
• Check for leaks in the radiator or cooling system components