Q: I own a Dodge Charger with the navigation radio. The joystick to control the cursor isn't working. Growing up in the city I hardly need to use the system (except when I go downtown). But now I can’t use it to control the selection folders of the MP3 function of the CD player. I took it to the dealer and they say, as I predicted, I need to replace the entire radio. This radio is nearly $2,000. I looked on E-Bay and I found the part that’s broken (for $30). That tells me this is a common problem. Is there a business that can fix this problem? Please advise. -- C.L., Chicago

A: C.L., according to some of the websites I visited, you’re right. The joystick appears to be a weak spot and it prompted a manufacturing revision. I searched the internet for “car radio repair” and found a long list of businesses. I’m sure if you contact some of them, you’ll find one that can help you out.

Q: I own a ’94 Ford Taurus wagon with a 3.8-liter engine. I keep putting in transmissions because they’ve been wearing out. The problem that I’m currently having is that when slowing down, there’s a very harsh downshift when the transmission shifts from 3rd to 2nd. The downshift is so harsh that it almost puts you into the windshield. I’ve replaced the computer and all the sensors. I think it might be in the wiring and the Ford dealer said it would cost a lot of money to troubleshoot the wiring. If I can’t find out what’s wrong I’m going to have to junk the car. Do you have any ideas? -- E.N., Demotte, IN

A: E.N., you may want to seek the advice of a transmission shop. By the way, before digging into the wiring, the mechanical parts should not be overlooked. Your transmission could have trouble with the low-intermediate servo assembly. Maybe the springs for the servo are broken or damaged. The springs help cushion the shift. Another possible cause could be a problem with the 3-2 control valve in the valve body. A good transmission technician should be able to diagnose your transmission woes.

Q: The engine in my 2000 Chevy Monte Carlo (3.8-liter) never gets up to operating temperature. I’ve changed the thermostat twice. I’ve also changed the antifreeze. Still, the engine will not come up to temperature. Once the outside temperature gets warmer, like in the 40s or 50s, the engine reaches 195-degrees. But in the winter, the engine won’t get up to 195-degrees. Even though the engine won’t get up to temperature, there’s plenty of heat inside the car. I’m baffled why the engine won’t get up to 195-degrees in the winter. I don’t want to replace another thermostat. I don’t know what to do anymore. Please advise. -- J.B., Orland Park

A: J.B., if you’re getting good heat inside the car in the winter I wouldn’t be too concerned. But to be sure there’s nothing wrong, take your car in to see if the engine coolant temperature sensor is indicating a different temperature than your dash-mounted gauge. To do this, a technician will need to use a scan tool. If the readings are different, there could be something wrong with the gauge or its wiring.

AutoAdviser: Ira Siegel is an Automotive Instructor and ASE Certified Master Auto Technician. If you have auto-related questions for Ira Siegel you can call and leave your questions at the Auto Adviser Hotline at 708-633-6839 or e-mail a question to Autoadvisr@aol.com.