P0183 Code: Fuel Temperature Sensor A Circuit High
The fuel temperature signal sits near 5 V, as if the sensor were unplugged; the PCM reads the fuel as frozen.
Safety first · Consult a professional
- Fuel vapor is flammable. No smoking or open flames; work outdoors and fix fuel leaks before driving.
At a glance
Severity: Low
- Meaning
- Fuel Temperature Sensor A Circuit High
- System
- Fuel & Air Metering · Powertrain
- Safe to drive?
- Yes, short term
- Typical repair cost
- $0–$1,000
- DIY difficulty
- Easy
With the sensor connected, the fuel temperature signal should sit somewhere between roughly 0.5 and 4.5 V depending on how warm the fuel is. When the circuit is broken, nothing pulls the PCM's 5 V supply down and the signal floats to the top of the range, which the PCM reads as its coldest possible value, typically -40 °F. P0183 is therefore an open-circuit code in most cases: a connector not clicked home, a broken wire, a corroded terminal, a lost sensor ground or a sensor that has failed open. It is especially common right after a fuel pump, sender or fuel filter replacement, because the sensor's plug is easy to miss or to seat only halfway. The engine usually runs normally on a default value.
Can I keep driving? Safe to drive in most cases. Diesels may start a little harder or run the fuel heater longer than needed, but there is no urgent risk; repair it before your next emissions test.
How to read P0183
- P Powertrain
- 0 Generic (SAE)
- 1 Fuel & air metering
- 83 Specific fault
Symptoms
- Check engine light on, often right after fuel pump, sender or filter work
- Fuel temperature in live data stuck at -40 °F regardless of weather
- EVAP monitor incomplete on many gasoline cars
- Diesel: slightly longer cranking or white smoke on warm starts on some engines
- Other sensors sharing the same ground may also read implausibly cold
Possible causes
Ranked by how often each cause is behind this code (editorial estimate).
- Sensor connector left off or not fully latched after fuel pump, sender or filter replacement
- Corroded or spread terminals at the sensor or at the tank-top connector
- Sensor open internally
- Broken signal or ground wire, often where the harness flexes near the tank or filter
- Aftermarket pump module without a working temperature sensor, or wrong sensor type fitted
- Open shared sensor ground at the PCM, usually setting several high-voltage codes at once
Diagnosis step by step
Check for other cold-reading codes
If intake air or coolant temperature codes are also set, or their values also read -40 °F, the problem is almost certainly a shared sensor ground rather than the fuel temperature sensor. Start at the PCM ground and its splices.
Tools: OBD-II scanner
Revisit recent fuel system work
If the fuel pump, sender or filter housing was changed recently, go straight to that connector. Check that the plug is on, latched and that the replacement part actually includes a temperature sensor, since some aftermarket assemblies differ from the original.
Tools: Flashlight, Screwdriver
Jumper test at the harness
Unplug the sensor, key on, and use a fused jumper to connect the signal pin to the sensor ground pin of the harness connector. The scan tool should jump to its hottest value. If it does, the wiring and PCM are fine and the sensor is open. If it stays at -40 °F, the fault is in the wiring.
Tools: OBD-II scanner, Multimeter
Measure the wiring
With the sensor unplugged, measure about 5 V on the signal pin to battery negative; if 5 V is there but the jumper test failed, the sensor ground is open. Measure the ground pin to battery negative: it should read under 5 ohms. Wiggle the harness while measuring to catch an intermittent break.
Tools: Multimeter
Test the sensor itself
Measure resistance across the sensor. An open reading (OL) or a value in the megohm range at room temperature means it has failed. Compare a good reading with the table for your sensor before buying the complete in-tank assembly.
Tools: Multimeter
Where the parts are
- 1Gas cap
- 2Charcoal canister
- 3Purge valve
- 4Vent valve
- 5Fuel pump
- 6Intake manifold
Repair options & costs
| Repair | DIY? | Estimated cost |
|---|---|---|
| Reconnect and latch the sensor connector | Yes | $0–$80 |
| Replace corroded terminals or connector pigtail | Yes | $50–$200 |
| Repair broken signal or ground wire | Yes | $90–$280 |
| Replace fuel temperature sensor on the fuel line or filter housing | Yes | $80–$250 |
| Replace in-tank sender or pump module with integrated sensor | No | $350–$1,000 |
Rough US estimates for parts and labor; shop rates vary by region. Not a quote.
Emissions / smog test impact
Will fail
A lit check engine light with P0183 fails an OBD-II smog inspection. The fix is often quick, but the EVAP monitor on many cars needs an overnight cold soak and a specific drive to complete, so allow a few days before testing.
Frequently asked questions
Why does the scan tool show -40 °F?
That is the coldest value on the PCM's table, and it is what an open circuit looks like. A thermistor that is disconnected or broken lets the signal float up to 5 V, which the PCM reads as extreme cold.
The code appeared right after a new fuel pump. Is the pump bad?
Usually not. The temperature sensor often shares the pump module's connector or has its own small plug nearby, and one of them was not seated properly, or the new module has no sensor or a different type. Check the connection before anything else.
Is P0183 the opposite of P0182?
Yes. P0182 means the signal is pulled toward 0 V and the fuel looks extremely hot, usually from a short to ground. P0183 means the signal floats high and the fuel looks extremely cold, usually from an open circuit.
Will P0183 hurt my engine?
Not directly. The PCM substitutes a default value and the engine normally runs as before. The real costs are the check engine light, a failed emissions test and, on diesels, fuel quantity corrections based on a guess.
Sources
- SAE J2012 – Diagnostic Trouble Code Definitions
- ISO 15031-6 – Road vehicles, diagnostic trouble code definitions (EOBD)
- Manufacturer public service information (cross-checked)
- Methodology: How We Build Code Pages · Data Sources We Use · Editorial Policy