P0182 Code – Fuel Temperature Sensor Circuit Low Input

The P0182 trouble code indicates that the fuel temperature sensor “A” circuit is reporting a low voltage signal to the ECU.

A “low input” condition usually means the ECU is receiving a voltage that is below the expected range, often close to 0V, which suggests:

• Short to ground

• Faulty sensor

• Wiring issue

The ECU interprets this as extremely high fuel temperature or an invalid signal.

How the System Works

The fuel temperature sensor operates as a thermistor:

• Low temperature → higher resistance → higher voltage signal

• High temperature → lower resistance → lower voltage signal

When voltage drops too low, the ECU assumes the fuel is excessively hot or the signal is faulty.

Common Causes of P0182

Electrical issues

• Short to ground in wiring

• Damaged wiring harness

• Corroded or loose connectors

Sensor failure

• Faulty fuel temperature sensor

• Internal short in the sensor

Installation issues

• Improper sensor installation

• Contaminated connector pins

Rare causes

• ECU input fault

• Incorrect aftermarket wiring modifications

Symptoms of P0182

• Check Engine Light ON

• Reduced fuel efficiency

• Hard starting (especially warm engine)

• Rough idle or unstable RPM

• Slight loss of power

• Possible limp mode (rare)

Is P0182 Serious?

Moderate severity.

• Engine will usually run

• ECU may use default values for fuel temperature

• Long-term effects:

  • Increased fuel consumption

  • Reduced engine efficiency

  • Higher emissions

How to Diagnose P0182

Step-by-step

1. Scan for codes

   • Confirm P0182 and check for related codes (P0180–P0184)

2. Check live data

   • Look for unrealistic fuel temperature (very high values)

3. Inspect wiring

   • Check for short to ground

   • Look for damaged insulation

4. Test sensor voltage

   • Verify reference voltage (usually 5V)

   • Check signal return line

5. Measure resistance

   • Compare with manufacturer specifications

6. Check connector condition

   • Clean corrosion and ensure tight fit

How to Fix P0182

• Replace faulty fuel temperature sensor

• Repair shorted wiring

• Clean or replace connectors

• Secure wiring harness

• Check ECU input if issue persists

Estimated Repair Cost (2026)

Can You Drive With P0182?

Yes, but not recommended long-term.

• Short-term driving is possible

• ECU may run in fallback mode

• Long-term use can reduce efficiency and increase wear

FAQ

What does “low input” mean in P0182?

It means the ECU is receiving too low voltage, usually due to a short to ground or faulty sensor.

Can a short circuit cause P0182?

Yes. A short to ground is one of the most common causes.

Will P0182 affect performance?

Slightly. It can lead to incorrect fuel calculations and reduced efficiency.

Conclusion

The P0182 code indicates a low voltage signal from the fuel temperature sensor circuit, usually caused by wiring issues or sensor failure. While not immediately critical, it should be diagnosed and repaired to maintain proper fuel management and engine performance.