Skip the auto shop - Our mechanics make house calls

P2740 OBD-II Trouble Code: Transmission Fluid Temperature Sensor B Circuit

check engine light

P2740 code definition

The P2740 Trouble Code indicates a problem with the trans fluid temp sensor B circuit.

What the P2740 code means

The powertrain control module has found that the transmission temperature, or the temperature sensor, is reading levels that are not within the limit put in place by the manufacturers.

What causes the P2740 code?

The following are the most common causes if the P2740 code:

What are the symptoms of the P2740 code?

One of the first things you will notice is that the Check Engine Light will come on and not go off. Many times, you will also smell transmission fluid that is overheated. The transmission could also smoke as well. When driving, you could notice that the transmission has trouble engaging, or that the transmission slips. All of these are bad signs and indicate that you need to get the vehicle to a mechanic as soon as you can.

How does a mechanic diagnose the P2740 code?

The mechanic will use an OBD-II scanner and connect it to the vehicle. They gather data from the onboard computer and they will use that to help them with their diagnosis. The information can help them get a better idea of what is really wrong with the vehicle. The mechanic will want to pay special attention to the vehicle’s transmission to make sure that they do not miss any issues.

Common mistakes when diagnosing the P2740 code

One of the big mistakes that mechanics make when they have the P2740 code is to believe that it is due to low transmission fluid levels or a leaking transmission. While it is true that this is one of the leading causes for the code to be present, that doesn’t mean that there aren’t also other issues with the transmission that need to be taken care of. They need to examine the transmission thoroughly.

How serious is the P2740 code?

Your transmission is essential for your vehicle to run properly, so it is not something you want to put off. When you have codes that deal with your transmission, it is important to get them taken care of right away. With the P2740 code, you will generally realize that you have problems with the transmission right away. Take the time to bring the vehicle directly to a mechanic who can diagnose the problem and make the needed repairs to the vehicles. If your transmission starts slipping, it is a sign of serious trouble. If the transmission goes out entirely, you will not be driving your vehicle.

What repairs can fix the P2740 code?

The following are some repairs that might be needed in order to fix the P2740 code:

  • The mechanic can use an OBD-II scanner to diagnose the vehicle. This ensures that the code is legitimate.

  • Check for transmission fluid leaks and low fluid levels.

  • Check wiring and connections. Make any needed repairs.

  • Rebuild or replace the transmission.

  • The powertrain control module could be at fault, although this is a rare occurrence.

Additional comments for consideration regarding the P2740 code

When a vehicle gets to be a certain age or has a substantial number of miles on it, there is always the chance that the powertrain control module might have some codes stored that aren’t actual problems. They may have been stored by mistake. However, you can’t trust in this. It is important that you always take your vehicle to a mechanic to get checked out. With the P2740 code, you are dealing with your transmission. If the transmission has a problem that isn’t fixed, it could become a serious issue.

Need help with a P2740 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How Long Does a Throttle Return Spring Last?
Not all vehicles on the road feature an electronic throttle control (ETC), which is also called drive-by-wire. For vehicles that don't offer this system, they have a throttle cable instead that...
P0222 OBD-II Trouble Code: Throttle/Pedal Position Switch/Sensor B Circuit Low Input
P0222 code definition Throttle/Pedal Position Switch/Sensor B Circuit Low Input What the P0222 code means The manufacturer specifies a range of acceptable voltage to be produced from the throttle position...
How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...


Related questions

Q: Car is reading trouble code PO136 01/01

Hi. There could be a couple of things going on here. There are multiple oxygen sensors on your car and sometimes what we think bank 1 is may not be and the wrong oxygen sensor is replaced giving us the...

Q: Running problem

Discount parts are always suspect and I would never advise anyone to use them for this reason. I recommend purchasing a reputable part. An often missed problem with diagnosing the MAF sensor are vacuum leaks. MAF stands for (mass...

Q: New battery & fuel pump. Hours later car starts and shuts down 3X in a row. Finally it starts, 48 hours later, won't start at all

Checking all the fuses was a good move. I would also want to put a scan tool on it and check for diagnostic trouble codes (DTCs) as well as seeing the data that the computer is seeing. A fuel pressure...