P274B code meaning
Transmission Fluid Temperature Sensor C Circuit Range/Performance
Powertrain system Generic code P27xx codes Check engine light
What P274B means
P274B means the sensor C signal is within electrical limits but does not fit the other information, for example because it barely changes while the gearbox warms or contradicts the other temperature values. The only public manufacturer reference is Ford bulletin 20-2044: 2020 Super Duty trucks with the 6.7 L diesel, built up to 5 February 2020, could light the MIL with P274B, often together with P203B and P2201, purely through PCM software; the remedy is reprogramming, about 0.6 h of labour. Ford does not say which measuring point C is. On other vehicles a sensor drifting with age, a high-resistance connection or contaminated fluid are more likely. P274A, P274C and P274D cover outright electrical faults.
P274B at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P274B
- Malfunction indicator lamp on
- Temperature C stays nearly constant while driving
Common causes of P274B
- Most likelyPCM software (Ford 2020 Super Duty 6.7 L, TSB 20-2044)
- PossibleSensor C drifting or slow to respond
- Less likelyAdded resistance in connector or lead
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Trans fluid temp sensor c
What each part of P274B means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 7 | Area: transmission. |
| 4B | The exact fault in that area. |
What to do next
- Note P274B 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 P274B
What does P274B mean?
P274B means "Transmission Fluid Temperature Sensor C Circuit Range/Performance". P274B means the sensor C signal is within electrical limits but does not fit the other information, for example because it barely changes while the gearbox warms or contradicts the other temperature values. It is a generic code, so it means the same on every make.
Is it safe to drive with P274B?
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 P274B fail an emissions test?
P274B is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is P274B to fix?
Difficulty: medium. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will P274B 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.