Fuel Temperature Sensor A Circuit Low Input
The P0182 code indicates that the Engine Control Module (ECM) has detected a voltage signal from the fuel temperature sensor (sensor A) that is lower than the expected range. This typically means the sensor circuit has a short to ground, a faulty sensor, or an open circuit. The fuel temperature sensor is a thermistor that changes resistance with temperature; a low voltage input suggests high resistance or a short, causing the ECM to see a very low or zero voltage.
01. Most Common Causes
- Faulty fuel temperature sensor
- Short to ground in the sensor signal circuit
- Open circuit in the sensor signal or ground wire
- Corroded or damaged connector at the sensor
- Faulty ECM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Hard starting, especially in cold weather
- Poor fuel economy
- Rough idle or hesitation
- Black smoke from exhaust (rich mixture)
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect the fuel temperature sensor connector and wiring for damage, corrosion, or loose connections.
Step 3: Measure the sensor resistance with a multimeter; compare to manufacturer specifications (typically 2-10 kΩ at room temperature).
Step 4: Check for voltage at the sensor connector with the ignition on; should be around 5V reference. If low, check for shorts to ground.
Step 5: If sensor and wiring are good, test the ECM by backprobing the signal wire and monitoring voltage while varying fuel temperature.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances with this code, as it can cause poor engine performance, increased emissions, and potential damage to the catalytic converter due to incorrect fuel mixture.
How much does it cost to fix?▼
The cost to fix P0182 typically ranges from $50 to $150, including parts (fuel temperature sensor) and labor. Diagnostic fees may add $50-$100.