Book Land Rover computer diagnostics at our Winter Haven shop. Same technicians, same bays, every time you come in.
5100 Dundee Road, Winter Haven, FL 33884
When a scan tool pulls a stored code off your car, what comes back is a number and a short description: a lean condition, a misfire on cylinder three, a circuit reading out of range. That tells us where the car noticed something wrong. It doesn't tell us what caused it. One lean code can come from a vacuum leak, a tired fuel pump, a dirty mass airflow sensor, or an exhaust leak sitting upstream of a sensor. Replacing the part named in the description works out sometimes. When it doesn't, you've bought a part and you still have the problem.
So the code is where we start, not where we stop. From there a technician watches live data while the engine runs, compares those readings against what the manufacturer says they should be, and tests the actual circuit or component with a meter, a scope, a pressure gauge, or a smoke machine. Sometimes it means driving the car until the fault shows itself. That testing is what turns a system into a part, and it's why diagnosis takes real time. It's skilled labor with real equipment behind it, the same as any other job in the shop, which is why it gets billed like one.
A free code pull at a parts counter is a useful thing to have. It tells you a code is stored and roughly what system it lives in, which is more than the dashboard gives you, and it costs you nothing. It's a starting point. What it isn't is a diagnosis, because nobody put the car on a lift, watched it run, or tested anything. If you already have the code, bring it. We'll use it. We'll just keep going from there.
Here's what paying for diagnostic time actually buys you. A named cause, meaning the specific failure we found and how we confirmed it, not a system and not a maybe. Photos of it on your phone from the digital inspection, taken on your vehicle that day. And a quote to fix it. Whether you do that repair, with us or anywhere else, is a separate decision and it stays yours. Plenty of people take the answer and go think about it.
The math on this is simple. Diagnosis costs what it costs, once. Guessing costs a part at a time until something works, and none of those parts come back. That's what you're really protected from here: paying for repairs that don't fix anything. Whatever we do fix carries a 36 month, 36,000 mile nationwide warranty, and every one of our six shops works the same way.
15 computer diagnostics jobs at our Winter Haven shop in the last 12 months.
Vehicle
What we found
2006 Jeep Wrangler
Fluid Leak Diagnosis · Oct 2026
The technician started with an initial assessment at no charge.
2020 Honda HR-V
Electrical Diagnosis · Oct 2026
The technician at our Winter Haven shop started with initial testing and an electrical diagnosis, which were performed at no charge.
I need to brag on Johnny’s automotive in Winter Haven. We had our check engine light come on last week and originally took it to another garage. They had our car all day from 8:00am on and waited til the end of the day when my husband called(they didn’t call us)to tell us that they couldn’t get to it until the following Tuesday! So I had to get a ride to go get it and then the next day we took it to Johnny’s. Johnny’s called us and said what they thought the problem was and had checked to see if it was still covered under our warranty because we have a 2022 car with relatively low mileage. Turns out that it was covered until November 5th! That’s next week! I feel like the hand of God protected us! But there’s more: this lovely girl named Sara from Johnny’s offered to drive our car to the dealership for us- it’s all the way in Lake Wales! My husband was at home (not close) and I was at work and we couldn’t get there, so she drove it there for us! Johnny’s didn’t charge us anything and Sara even called us back today to follow up with us. I am so impressed! This is very rare. If we ever have any more problems we will definitely go back there. We had excellent customer service! So thankful!
Gloria Wallman
Verified Google Review
This visit was my first and it definitely will not be my last. I have chosen to keep my car rather than trade it in every couple of years as I used to do. My check engine light came on and of course that means a lot of money out-of-pocket to repair the car. I found after a search on Google Johnny’s Automotive and the reviews were great. From the moment of my first call to them through yesterday was such an Stress-free experience. Two issues engine, check light and low tire pressure. They diagnosed it as an evaporator leak and that would require a smoke test costing over $200. The technician asked me about what I was doing when the light came on and I told him I had pump gas in the car. He began asking me a series of questions and he says OK. Let me look at a few things. We may have to do the test but I think maybe it might not be as bad as we think. He came back in a little later and said I think it’s the fact that you did not twist your gas cap on your car and it was just sitting there on top. He said I turned the check engine light on. It’s been running. The engine light has not come back on and rather than go to the expense of a test if you get in it and the light comes back on turn around come back. I said OK he said, but you have another problem and that is there is where on your tires and I was puzzled by that because the tires were not that old they had been on the car about a year the back tires were fine. The front tires were not long story short the tires that I had purchased and trusted a fine automotive store was manufactured in 2021 I bought them in 2026. In June I had a very high car repair at a major dealership. And they told me my cabin filter needed to be replaced and I said go ahead and replace it. When there’s no way in four months that could have been that dirty. I went in for two issues and because I am responsible only for myself they did an inspection of the car. Everything else was fine and I have driven the car now for 15 or so miles and the engine light is still off as of yesterday I will be not going to any dealership and I will not be going to my trusted auto shop that I have patronized for 10 years the staff at Johnny’s automotive are honest, kind, considerate, and knowledgeable. FWS
Freida Smith
Verified Google Review
I took my H3 in for electrical and safety issues. The service was exceptional! Great shout out to Jeffrey for having the most amazing customer service at the Winter Haven location. My truck had to be kept overnight and they gave me a loaner car. I have never experienced this at any other mechanic shop which puts them above the rest! My truck was successfully completed in a timely manner. If I could give more than 5 stars I would
TALITA JOHNSON SMITH
Verified Google Review
Ms. Cece, Mr. Art, Mr. Jeffrey and the entire Johnny's Automotive family are wonderful people, experienced and exhibit the utmost pride in their work and professionalism. I took my wife's 2017 Lincoln MKC to the one place that I knew would take care of my wife's car. It's her main drive and she's going back and forth from Winter Haven to Tampa almost daily. Johnny's Automotive and team probably saved me thousands of dollar in an unnecessary (for now) turbo repair for what turned out to be a vacuum leak affecting my wife's cars power and check engine status. Full break service has left her car braking smooth. She's now happy and most importantly, reassured, that she'll be safe in her car. You can't put a $$$ on that kind of peace of mind, for both my wife and myself. Thanks Cece, Art, Jeff and team! We'll be back next lil change to do tune-up and leave my wife's car like it was when it rolled off the lot new!
Mr Morales
Verified Google Review
Professionalism from the start, great communication, and quick delivery time. I took my vehicle to Johnny’s Automotive for what I thought was an AC problem, but they quickly found it was actually an overheating issue and an oil leak. Before coming here, I was scammed by Agua Wash and Lube, who falsely claimed my AC was recharged and had a leak. Just two hours later, the same issue came back. Johnny’s team found the freon was low and diagnosed the real problem with honesty and care. This is a credible, veteran-friendly shop that treats locals and visitors with integrity. Highly recommend!
frania zamora
Verified Google Review
I took my car to Johnnys and I’m glad I did. The mechanics here actually took the time out to find out why my car was making a funny noise when my ac is on. They Called and explained everything to in detail. Unlike Firestone said it was my transmission and dual fan assembly that needed to be replaced. I like that I wasn’t taken advantage of by Johnnys and they are priced reasonably. I highly recommend them. 🙌🏽🙌🏽🤞🏽🤞🏽
Alesia Myers
Verified Google Review
Pick whichever one is easiest to drive to.
ASE Certified Technicians
ASE certified techs working on your vehicle
Flexible Drop-Off Hours
Convenient service options
20+ Years
2 decades of trusted service
