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

Symptoms of a Bad or Failing Flexible Clutch Hose
Common signs include difficulty shifting, low clutch fluid, and feeling no resistance at the clutch pedal.
How to Find the Keyless Code on a Ford Explorer or Mercury Mountaineer
Many Ford Explorers and Mercury Mountaineers were manufactured with an option known as the Ford keyless entry keypad. Some models refer to it as SecuriCode as well. It...
The Traveler’s Guide to Driving in Malaysia
CraigBurrows / Shutterstock.com Malaysia is a popular destination for many tourists today. The country has amazing sights and attractions that you will want to explore....


Related questions

Q: engine wont restart when hot, no spark P0340 has 12v on both connectors, freq from 5-11hz when cranking

Since the crank position sensor gets its timing signal off the damper, I would first replace the damper to be sure timing was correct. The fact that this failure occurs after a "heat soak" cycle, and the P0340 code is...

Q: Barely any power when I step on the gas pedal, any ideas?

Hello. From the symptoms you describe it would appear that your vehicle is experiencing an issue that is putting it into some sort of limp mode. Limp mode is activated when the computer detects an issue that could potentially damage...

Q: Throttle body position sensor

The rumbling noise may be coming from the loose catalyst in the exhaust piping. It would need to be verified by a road test to listen to the noise. If the catalyst is breaking up in the exhaust then the...