P1299

Ford

Cylinder Head Overtemperature Protection Active

Definition source: Manufacturer reference catalog
Definition verification: Not independently verified for display.
Time: Varies by diagnosis and vehicle | Diagnostic difficulty: Medium
High Severity

The engine computer detected a cylinder-head overtemperature condition and activated an engine-protection response. Depending on the vehicle, that response may reduce engine power. The code identifies the detected condition; it does not by itself prove that a particular part has failed.

Report an error with this code

⚠️ Before You Begin (Safety First)

Treat this as a potentially serious overheating condition. If the temperature warning is on, the gauge is high, steam is present, or the engine is losing power, pull over safely and shut the engine off. Do not open a hot cooling system. Continuing to drive while overheating can cause severe engine damage.

Common Symptoms

  • An engine-temperature warning or high temperature reading may appear if the engine is genuinely overheating.
  • Engine power may be reduced if the protection response limits operation.
  • Poor running or an engine that shuts down may occur if overheating becomes severe.
  • Coolant loss, steam, or a coolant odor may be present when a cooling-system fault is involved.
  • There may be no obvious symptom if the condition was brief or the reported temperature signal is inaccurate.

Common Causes

  • The engine may genuinely be overheating because of low coolant, a leak, restricted heat transfer, or a cooling component that is not working properly.
  • A temperature sensor or its wiring or connections may report a temperature that does not match the engine's actual condition.
  • An intermittent electrical fault may cause the overtemperature condition or protection status to be reported inconsistently.
  • The underlying cause cannot be identified from this code alone; diagnosis depends on the vehicle's engine and cooling-system design.

Diagnostic Steps

  1. When the engine is fully cool, check the coolant level using the vehicle's specified procedure. Do not remove a pressure cap while the system is hot.
  2. Look for visible coolant leaks or damaged hoses around the engine and cooling system. Avoid touching hot or moving components.
  3. Note whether the temperature warning, high gauge reading, reduced power, steam, or coolant odor occurs, and stop driving if overheating signs appear.
  4. If a suitable scan tool is available, record the code and relevant temperature data without clearing the code before diagnosis.
  5. If coolant is low, a leak is found, the warning returns, or the reported temperature does not match the engine's condition, arrange professional diagnosis before further driving.

When to Call a Professional

Confirm the code and review available temperature and protection-status data. Compare the reported temperature with the engine's actual condition, then inspect the cooling system for coolant loss and test relevant sensor circuits and cooling components using model-, year- and engine-specific service information. Do not replace a sensor based on this code alone.

Compare component listings

Confirm diagnosis and vehicle fitment before buying. A listing does not prove that a part needs replacement. We may earn a commission from qualifying purchases.

Search Amazon Search eBay

Commonly Asked Questions

Does P1299 prove that the cylinder-head temperature sensor has failed?

No. It indicates that cylinder-head overtemperature protection became active. The engine may actually be overheating, or a sensor, connection, or circuit may be reporting an inaccurate condition.

Can I keep driving with P1299?

Do not continue if the temperature warning is on, the gauge is high, steam is present, or power is reduced. Stop safely and shut the engine off; driving while overheated can cause severe damage.

Why might the engine have reduced power?

The vehicle may limit engine operation as part of its overtemperature protection response. The exact response depends on the model, year, and engine.

What should be checked before replacing parts?

Check for a genuine overheating condition and coolant loss, then assess temperature data and the relevant sensor wiring and connections. The code alone does not identify the failed component.

Browse Available Code Guides

Previous and next available guides in database record order, across makes. Adjacent entries may share a code number and do not necessarily describe related faults.