P0185 code meaning
Fuel Temperature Sensor B Circuit
Powertrain system Generic code P01xx codes Check engine light
What P0185 means
Fuel temperature sensor B is an NTC thermistor: the hotter the fuel, the lower its resistance and signal voltage. On diesels it sits in the injection pump, rail or return line; on Ford gasoline direct-injection engines it is built into the rail pressure sensor, and GM uses digital rail temperature sensors on its direct-injection engines. Sensor B is the second measuring point, for example GM's 6.6 litre diesel sensor 2 or a second rail. P0185 is the general circuit fault of this sensor, the counterpart of P0180. None of the manufacturers checked uses it; GM reports sensor 2 faults as P0187/P0188. No manufacturer document using exactly this code was found; the description rests on CARB's circuit monitoring requirement and component information.
P0185 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 2 hours
- Clears after repairAfter a drive cycle
Symptoms of P0185
- Check engine light on
- Substitute value, usually no change in driving
Common causes of P0185
- Most likelyWire or connector open or corroded
- Most likelySensor faulty
- Less likelyControl module reference or ground
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Fuel temperature sensor bSensor wiring
What each part of P0185 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 1 | Area: fuel and air metering. |
| 85 | The exact fault in that area. |
What to do next
- Note P0185 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0185
What does P0185 mean?
P0185 means "Fuel Temperature Sensor B Circuit". Fuel temperature sensor B is an NTC thermistor: the hotter the fuel, the lower its resistance and signal voltage. It is a generic code, so it means the same on every make.
Is it safe to drive with P0185?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P0185 fail an emissions test?
Yes, it can. P0185 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0185 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2 hours of work. This is a job for a workshop.
Will P0185 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.