Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the computer in your car thinks the temperature sensor for the engine is not changing like it should. It's like a thermometer that always shows the same temperature, even if it's getting hotter or colder.
The P3199 code is triggered when the Engine Control Module (ECM) detects that the engine coolant temperature sensor signal is not varying as expected. This could indicate that the sensor is stuck or malfunctioning.
The Engine Coolant Temperature (ECT) sensor provides the ECM with information about the engine's temperature. If the sensor's signal remains constant over time, the ECM interprets this as the sensor being stuck. This can lead to improper air-fuel mixture adjustments and affect engine performance.
• Check Engine Light is on
• Poor fuel economy
• Engine overheating or running cold
• Faulty engine coolant temperature sensor
• Wiring issues such as shorts or open circuits
• Corroded or damaged sensor connector
ECM: Engine Control Module, the computer that controls the engine's functions.
ECT Sensor: Engine Coolant Temperature Sensor, a device that measures the temperature of the engine's coolant.
• Use an OBD-II scanner to confirm the P3199 code.
• Inspect the ECT sensor and its wiring for damage or corrosion.
• Test the ECT sensor's resistance and compare it to the manufacturer's specifications.
• Replace the engine coolant temperature sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Socket set
$100 - $200
Moderate
• Toyota Camry
• Honda Accord
• Ford Focus
• Regularly check and maintain coolant levels.
• Inspect sensor wiring and connectors for damage.
• Schedule routine maintenance checks.
Sensor Issue
• Do not ignore the Check Engine Light.
• Monitor engine temperature gauge for unusual readings.
• Seek professional diagnostics if unsure.
Check with your vehicle manufacturer for specific warranty coverage related to sensors.
The P3199 code has been associated with vehicles that have aging sensors or issues with wiring harnesses.
Moderate – It is advisable to address this issue soon to avoid potential engine performance problems.
Driving with a malfunctioning temperature sensor can lead to engine damage. Ensure repairs are conducted by a qualified technician.
• Engine at operating temperature
• Ignition in the 'on' position
The engine coolant temperature sensor is typically located near the thermostat housing or on the engine block.
Q: What happens if I ignore the P3199 code?
A: Ignoring this code can lead to poor engine performance and potential overheating, which may cause engine damage.
Q: Can I drive my car with the P3199 code?
A: While the car may still be drivable, it is not recommended to ignore the issue as it can lead to further engine problems.
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Fitment Required · Vehicle-fitment part
Relevant when coolant-temperature and warm-up faults indicate a thermostat-related issue.
Coolant-temperature and warm-up faults often lead to thermostat testing and replacement.
Thermostats are vehicle-specific and should be matched by engine and housing style.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.