Comparing code readers and scan tools

Q. I have a newer Toyota Camry and an older Ford F-150. What does a scanner do that a code reader cannot do? Can you recommend one that you have found acceptable?

A. A code reader will read most generic codes, clear codes, and turn off a check engine light. Some code readers will give a short description of the code. A scan tool can access more systems such as airbag, ABS brakes, steering and suspension, and body control modules. Most scan tools can read manufacturer specific codes. Better scan tools allow you to perform bi-directional testing by commanding certain components on/off. Scan tools vary by budget. I have a Harbor Freight T-10 tablet-style scan tool. It is solid, reliable, and has functions that rival scan tools that cost three times as much. I also have an Innova scan tool (5610) that is simple to use and also has bi-directional capabilities. The Innova tools also have access to the Repair Solutions2 that provides verified fixes. A scan tool, even the most expensive, will not fix problems, they will help guide you to a possible issue and possible solution. 

Q. I drive a Toyota RAV4 hybrid with all-wheel drive. I would rather rotate tires front to back and back to front when the front tires are halfway worn. Does that fraction of an inch matter on an all-wheel drive vehicle?

A. Ideally, it is best to rotate tires before you see uneven wear. All-wheel drive systems perform best and last longer when tires are the same size. Toyota does not have a specific measurement to what is acceptable wear or not. A fraction of an inch should not matter, but ideally rotate the tires on your RAV4 once or twice per year. This is also a good excuse to check the steering, suspension, and brakes for abnormal wear. 

Q. Some of the questions you answer make me laugh. I ran my own repair shop for years and still do minor repairs at my home shop. As you have pointed out many times, some answers can be found in the owner’s manual and others should just be common sense. Also the people who drive luxury cars who complain about the cost of repairs and even the cost of using premium fuel. How do you keep a straight face? 

A. I still follow the philosophy that the only dumb question is the one you don’t ask. If the question and answer is important to one-person, chances are it is important to someone else. Although every question may not end up in the paper or online, every question gets a personal reply, even the questions that make me smile. 

Q. I have a 2010 Chrysler 300S with 81,000 miles. My wife has a bad shoulder and now has a harder time turning a corner. When you turn a corner and let go of the steering wheel it only comes back halfway then you have to finish turning the wheel to have the car straighten out. When she uses my Honda it’s much easier to turn the steering wheel and it returns completely. I know some cars have a switch or button to change back and forth to make it feel like a sports car. Is there anything on this model Chrysler that controls this or is this a power steering pump problem.

A. The 2010 Chrysler 300 (including the sportier 300S trim) uses a traditional hydraulic power steering system with a belt-driven pump, not an electric power steering (EPS) setup, so unfortunately there is no option to adjust steering feel. At this point there may be nothing wrong with the car, but it couldn’t hurt to check the steering system as well as the alignment. There are three main alignment angles, and excessive caster combined with worn parts can cause slow steering wheel return. 

Q. My son has a 2025 Jeep Grand Cherokee and I have a 2023 Toyota 4Runner. Neither car has remote car starting. He mentioned to me he was going to have it installed and it was a feature I had always wanted, so I said let’s both go together and get it done. We went to a long-established local (independent) place that strictly does automotive sound and security work. When we got the call that the installation was done, we went to pick the cars up and we were each given a demo on the feature. On my Toyota, after the self-start feature is activated, when you open the driver’s door the car shuts off. Then it has to be restarted normally when you get into the driver’s seat. On my son’s Jeep that isn’t the case. The installer said that this is a built-in safety feature in Toyota, Mazda, and other brands which cannot be avoided. I have to tell you, I find it a little annoying that I have to restart the car. Just wondering if you have heard this and whether what he’s telling me is true.

A. Yes, that is a safety feature and my last Toyota with the factory remote start did the same thing. The following is a quote from a Toyota manual: “The remote engine starter is designed to shut the engine off when it detects any attempt to enter or move the vehicle after a remote engine start.” Is there a way around it? Probably, but not easily, and not recommended by Toyota.  

John Paul is AAA Northeast’s Car Doctor. He has over 40 years of experience in the automotive business and is an ASE-certified master technician. E-mail your Car Doctor question to [email protected]. Listen to the Car Doctor podcast at johnfpaul.podbean.com.