Why did my Nissan Murano lose its Bluetooth function? | Car Doctor

Q: I have a 2012 Nissan Murano and I lost the Bluetooth function. Is it a fuse problem, or something else?

A: Nissan uses a separate Bluetooth module. It could be that the module is faulty or the wiring to the module.

If you don’t see a Bluetooth display on the radio screen, the module is likely the issue.

If you see Bluetooth and your phone won’t display, then it could be a compatibility issue (new IOS update). You might want to look for updates from the manufacturer. Go to nissanusa.com/bluetooth for more information.

What’s the best temperature range for applying automotive touch-up paint?

Q: What is the lowest temperature that automotive touch-up paint can be applied?

A: Automotive touch-up paint is best applied between 50 and 90 degrees. And, just like painting at home, good preparation is the key to a quality finished product.

What’s causing transmission oil to overheat in Jeep Cherokee?

Q: My 2007 Jeep Cherokee has approximately 130,000 miles on it. The oil light occasionally came on when the oil level was full. Recently, it refused to start at the gas station after a short drive. I got a message that the transmission oil was too hot. The car was towed to a garage and, 48 hours later, it started up perfectly and repeatedly for the mechanic. What might be the cause?

A: The oil light may be a separate problem and should be checked separately by using a mechanical gauge to see if the oil pressure is low or if it is a faulty gauge or sender.

The transmission overheat warning, and the no start, may be related.

Looking at the wiring diagram, it appears that the temperature of the transmission oil has a considerable effect on the shifting time and therefore the shift quality. By measuring the oil temperature, shift operations can be optimized in all temperature ranges.

The transmission oil temperature sensor is switched in series with the park/neutral contact.

The temperature signal is transferred to the computer when the contacts of the park/neutral contact is closed in reverse or a forward gear position. Since the park/neutral switch and the transmission temperature sensor are wired in series, I would be looking at the sensor and wiring.

What are possible causes of the brake light coming on?

Q: Yesterday my brake light came on in the console. This is my first vehicle, and I’m wondering if that light, or the work it may be signaling for, is an issue. Where would you suggest I go to have the car looked at?

A: If it is a red brake light, the parking brake may be partially applied, or the car is low on brake fluid.

If the light is still on and the parking brake is fully released, then it could be a brake fluid issue or a more serious brake issue that could make the vehicle dangerous to drive.

If it is an amber brake light, that would be an issue with the car’s antilock brake system (ABS), and the car is safe to drive but the ABS feature won’t work.

As for getting the car repaired, you could go to an AAA-approved repair shop. To find a AAA shop near you, go to aaa.com/repair.

How do CVTs differ from other kinds of automatic transmission?

Q: What are CVT transmissions? Can you compare these transmissions to other types of automatic transmissions? Also, do CVTs have a short life span?

A: Continuously variable transmissions (CVT) don’t have gears in the traditional sense; they use a belt and variable diameter cones to change speeds. Similar to how a 10-speed bike has five gears on the back and two gears on the pedal sprocket – think of those gears as cones with infinite combinations.

The idea is that the engine is always in the sweet spot for engine speed and fuel economy. It works better in theory than in practice, but these transmissions are getting better all the time.

CVT longevity also seems to be improving. There was a time when a CVT barely made it past the warranty period, but now we are seeing 200,000 miles. Still, call me old-fashioned, but I prefer a conventional automatic with actual gears.

John Paul, Car Doctor

John Paul is the AAA Northeast Car Doctor. He has more than 40 years of experience in the automobile industry and is an ASE-Certified Master Technician. Write to John Paul, The Car Doctor, at 110 Royal Little Drive, Providence, RI 02904. Or email jpaul@aaanortheast.com and put “Car Doctor” in the subject field. Follow him on Twitter @johnfpaul or on Facebook.

This article originally appeared on The Providence Journal: Why did my Nissan Murano lose Bluetooth function? | Car Doctor