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P1299MinorPowertrain

P1299 on 2005-2010 Ford Mustang — Cylinder Head Over-Temperature Protection Active (manufacturer-specific, Ford)

1 vehicles · 1 makes · $250-$700 repair

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Most Reported On

2005-2010Ford Mustang

P1299 is an OBD-II diagnostic trouble code meaning “Cylinder Head Over-Temperature Protection Active (manufacturer-specific, Ford).” P1299 is a manufacturer-specific powertrain code, most commonly on Ford, indicating that the Cylinder Head Temperature (CHT) sensor detected an engine overheating condition and the computer has activated a fail-safe cooling strategy to protect the engine. The PCM may reduce power and shut off fuel to some cylinders to limit heat, often putting the vehicle in a limited 'limp' mode. This means the engine is running too hot and continued driving risks serious engine damage, so the vehicle should be stopped and cooled as soon as it is safe. This code is most commonly reported on 2005-2010 Ford Mustang, with repair costs ranging from $250 to $700.

On This Page

  • Common Causes
  • Repair Cost
  • Vehicles (1)
  • Related Codes
  • FAQ
  • Sources (1)
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Common Causes

1Low coolant level or coolant loss/leak
2Stuck-closed thermostat
3Failed water pump
4Cooling fan not operating
5Faulty cylinder head temperature (CHT) sensor
6Blocked radiator or restricted coolant flow
7Head gasket failure or air in the cooling system

Typical Repair Cost

$250 - $700

Based on 1 documented vehicle-specific issues. Actual cost depends on root cause and vehicle.

Diagnostic Tools

To diagnose P1299, you'll need an OBD-II scanner. Here are our recommendations at every price point.

Budget Pick$10–$20

ANCEL AD310 Classic OBD-II Scanner

by ANCEL

A simple, affordable code reader that reads and clears check engine codes. Great for quick diagnostics on any OBD-II vehicle (1996+).

  • Read & clear engine codes
  • View freeze frame data
  • I/M readiness status
  • No batteries or app needed
Check Price on Amazon
Best Value$90–$120

BlueDriver Pro Bluetooth Scanner

by BlueDriver

Bluetooth OBD-II scanner with a free companion app. Provides enhanced diagnostics, smog readiness, and repair reports sourced from a database of verified fixes.

  • Enhanced diagnostics (ABS, SRS, transmission)
  • Repair Reports with verified fixes
  • Smog check readiness
  • Free app (iOS & Android)
Check Price on Amazon
Advanced$180–$230

LAUNCH CRP123X OBD-II Scanner

by LAUNCH

A professional-grade handheld scanner that reads all four major systems (engine, transmission, ABS, SRS) with live data streaming and graphing.

  • Engine, transmission, ABS, SRS diagnostics
  • Live data stream & graphing
  • AutoVIN for vehicle identification
  • Free lifetime updates via Wi-Fi
Check Price on Amazon
Professional$350–$450

Autel MaxiCOM MK808S Diagnostic Tool

by Autel

Shop-level diagnostic tablet with bi-directional control, active tests, and full system coverage. Ideal for serious DIYers and small shops.

  • All-system diagnostics (25+ modules)
  • Bi-directional control & active tests
  • Oil reset, EPB, BMS, TPMS, injector coding
  • 7-inch touchscreen with Android OS
Check Price on Amazon

As an Amazon Associate, we earn from qualifying purchases. Prices are approximate and may vary.

Vehicles Affected (1)

Ford P1299 page →
MustangModerate

4.0L Cologne V6 Thermostat Housing Cracking and Coolant Leaks

2005-2010$250-$7000 reports

Related Codes (8)

P1298Injector Driver Module (IDM) Failure / Electrical Load Detector Fault (manufacturer-specific)P0020Camshaft Position 'A' Actuator Circuit (Bank 2)P0034Turbocharger/Supercharger Bypass Valve Control Circuit LowP0035Turbocharger/Supercharger Bypass Valve Control Circuit HighP003ATurbocharger/Supercharger Boost Control 'A' Position Exceeded Learning LimitP0046Turbocharger/Supercharger Boost Control 'A' Circuit Range/PerformanceP0089Fuel Pressure Regulator 1 PerformanceP0093Fuel System Leak Detected - Large Leak

FAQ

What does P1299 mean?

P1299 stands for "Cylinder Head Over-Temperature Protection Active (manufacturer-specific, Ford)." P1299 is a manufacturer-specific powertrain code, most commonly on Ford, indicating that the Cylinder Head Temperature (CHT) sensor detected an engine overheating condition and the computer has activated a fail-safe cooling strategy to protect the engine. The PCM may reduce power and shut off fuel to some cylinders to limit heat, often putting the vehicle in a limited 'limp' mode. This means the engine is running too hot and continued driving risks serious engine damage, so the vehicle should be stopped and cooled as soon as it is safe.

What are the most common causes of P1299?

The most common causes of P1299 are: Low coolant level or coolant loss/leak, Stuck-closed thermostat, Failed water pump, Cooling fan not operating, Faulty cylinder head temperature (CHT) sensor, Blocked radiator or restricted coolant flow, Head gasket failure or air in the cooling system. The specific cause varies by vehicle.

How much does it cost to fix P1299?

Repair costs for P1299 range from $250 to $700, depending on the vehicle and root cause.

Which vehicles are affected by P1299?

Au7o has documented P1299 across 1 vehicle models from 1 manufacturers: Ford.

Sources (1)

  • ForumCarComplaints - Ford Mustang cooling system complaints (4.0L thermostat housing leak reports)

Content compiled with AI assistance using NHTSA complaints, TSBs, and owner reports. May contain errors. Always verify with your vehicle's service manual.

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