Question

What is code P1299?

A P1299 error usually means an issue with the temperature of your car's engine.   

The OBD2 code P1299 generally indicates an overheating engine in your car. Since the P1 codes in OBD2 are non-standard, the car manufacturers can define them on their own. Therefore, the definition and fixes for the code vary based on the make and model. Still, you can find some common symptoms and fixes for P1299.   

P1299 Code 

The P1299 code means your engine’s temperature is too high. CHT constantly detects and sends the metal temperature to the Powertrain Control Module. Receiving the temperature figures, PCM compares them with the normal range and flags P1299 if the current range is above the allowed figures. This can be due to several reasons, and the temperature is maker-specific. Hence, each make and model has its own high temperature.   

P1299 Symptoms   

Some of the common symptoms of P1299 are:   

• Check Engine Light turns ON.   
• The engine automatically shuts down.   
• The engine takes longer to start.   
• Reduced performance   
• Vehicle enters limp mode.   

Low fuel efficiency   

Before starting with possible P1299 code fixes, make sure there are no other active codes. The mentioned symptoms can occur due to various underlying issues other than P1299.   

P1299 Causes   

Here are some of the possible causes of the error code P1299:   

• Loss of coolant or low coolant: A Sufficient coolant level helps to maintain optimum temperature for the engine. Therefore, no or low coolant leads to overheating in the engine. This can be a result of damaged hoses, radiator holes, or vaporization of coolant.   
• Low coolant circulation: Due to a faulty water pump, clogged radiator, or thermostat, the coolant circulation is affected.   
• Faulty Thermostat: A bad thermostat can cause the coolant to overflow. As the coolant overflows through the thermostat housing, the engine overheats.  
• Faulty CHT sensor: The Powertrain Control Module compares data from the CHT sensor with the allowable temperature. When PCM receives wrong or faulty data from the sensors, it triggers the symptoms of P1299.   
• Damaged connections: A faulty circuit in the cooling system can also cause a P1299. This can be due to burned, corroded, or shorted wiring in the system.   

Damaged radiator cooling fans, water pump failure, and improper airflow can also be the causes of the OBD2 code P1299.   

Driving with a P1299 code   

Once the PCM triggers P1299, it means that the control module is initiating a Fail-Safe mode. As the overheating causes severe damage to the engine, the fail-safe mode lets the engine perform in the available environment. As a result, the ignition timing may vary, fuel economy and car performance may go down. Ignoring the code and driving more leads to major damage, such as piston damage, a blown head gasket, damage to the catalytic converter, etc. Once P1299 is detected, let the engine cool down before attempting the fixes.   

Fixes for code P1299   

A complete fix for P1299 depends on your car’s make, model, and the underlying issue. You might find the maker-specific definition for the code in your car manual. Some of the common fixes for the P1299 code are:   

• Check for fluid leaks.   
• Check for damaged circuitry in the cooling system.   
• Replace the cylinder head.  
• Clean the radiator.   

All the same, get professional advice and service to detect more complex issues like a faulty sensor or thermostat, which can also trigger a P1299.