Why do I get a 'no signal' message on my radio when I listen to HD FM radio? | Car Doctor

Q: I drive a 2016 Mazda CX-5. I did not sign up for SXM satellite or Pandora, and I get a “no signal” message on the radio. I have only listened to HD FM radio. I refuse to pay the dealership charges of $230 for diagnostic services. So, if there is a designated automotive shop that can resolve the issue that will not drain my pocket, I’d appreciate it. FYI, the radio does not have an “off and on” option. You can only mute it.

A: If the radio is the stock radio, the volume button is also the on/off button. Push to turn on and off.

From this point, push the audio button and, on the screen, you should see a selection of AM/FM, FM HD, SXM and other input sources. If this does not work, then try a radio reset. Reset your radio by pressing the music, navigation and volume buttons at the same time. Press the three buttons simultaneously for at least 20 seconds. The system should then automatically reboot itself.

Did I get ripped off on brake caliper replacement?

Q: I recently had my 20-year-old car into a repair shop for brake work. The owner told me that I would need new brake calipers. The reason was because the caliper bolt was rusted frozen and broke off when they tried to remove it. I had them replace both calipers. When I got home, I told my son about this, and he said the mechanic should have just drilled out the bolt and not replaced the caliper. Did I get ripped off?

A: This is really a matter of economics. Yes, the mechanic could have drilled out the bolt, but it is a hardened steel bolt and would have taken a long time and maybe more than one drill bit, which you would ultimately pay for in labor costs. Replacing the caliper is quicker, and having new calipers on your 20-year-old car will provide better and safer braking.

Is it too risky to buy my dream 1970 Camaro from an online auction?

Q: Would you buy a 1970 Chevy Camaro from an online auction? This was the car I dreamed of in junior high school. Now I have the means to buy one. I have seen these cars on auction sites, and the problem is they all look beautiful, but they are 53 years old, so I am concerned.

A: Before I'd spend my money on a dream car, I would have a friend help me who has no emotional attachment to the car.

All sites have dozens of pictures of the car, which I would put on the largest computer display so you can find and look for previous repairs.

If there is a video, how does the engine sound? Do a little pricing research to determine a realistic price, and do not let your feelings for the car override your price point. Remember, too, that there may be a buyer premium, and you would need to transport this car, which would also add to the price.

Diagnosing the PO300 code on a 2017 Chevy Cruze

Q: I have a 2017 Chevy Cruze that runs great but has a code and check engine light. The code is for a misfire PO300. I have checked for vacuum leaks and replaced the spark plugs and ignition coil. What can the problem be?

A: I have seen some issues with carbon build-up on the valves, which can cause this code. The engine will run fine, but the crankshaft position sensor — which is quite sensitive — will detect a very slight misfire. Perhaps try a good combustion chamber cleaner.

The second — and somewhat weird — issue is that if one of the accessories on the engine is not tight (such as the alternator bracket), this vibration can sometimes cause the PO300 code to pop up.

How to find the source of an antifreeze leak

Q: I have 2013 Lexus RX 350 that is a great vehicle, but occasionally I see what looks like antifreeze under the car. When it was in for an oil change, I asked them to check it. They said they did not find anything wrong. Is there something common that the oil change place just missed?

A: The best method to look for a leak is how we have been doing it for decades. Fill the radiator, apply pressure, and see if the gauge on the tester holds pressure. If the pressure drops, carefully inspect all of the cooling system. This would include the radiator, water pump hoses and the engine itself.

On a 10-year-old Lexus, I would be focusing on the water pump and hoses. If it is the water pump, expect to spend about $800 to $1,000 for the part, supplies/hoses and labor.

AAA's Car Doctor, John Paul
AAA's Car Doctor, John Paul

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 do I get a 'no signal' message on my radio? | Car Doctor