Gonzo’s Tool Box: Shift Happens – UnderhoodService

Gonzo’s Tool Box: Shift Happens

Jo was a new customer referred by an old-time regular. Her little KIA had a transmission problem that seemed to be getting the best of the transmission shop. The story goes that the SUV was constantly in limp mode, and would never shift properly ... ever.

As it always seems to be the case when a simple problem can’t be solved simply, somebody started the diagnostics off in the wrong direction.  Little did I know this was a simple problem. But, as I see it, any type of diagnostic work that you do requires a certain step-by-step procedure that you must follow. Missing a step, or completely overlooking a step, usually means you’re going to miss that simple problem all together. This was no exception.

From what information I could gather, the person who diagnosed it at the transmission shop wasn’t the same person who installed it.  So after the tech put the last bolt in the transmission, he set the car out front, and told the front office, “Got the transmission in that KIA.”  The front office considered it done, and the call went out for Jo to pick it up.  She didn’t make it around the block before she was back at the front counter in a “not-so” pleasant mood. You can just imagine the situation at the counter … not pleasant I’m sure.  After some deliberation, and very little diagnostics, the transmission shop came up with the conclusion that it must be a bad transmission.  Luckily, Jo’s ride that had brought her there was still in the parking lot so she left the KIA for them to re-do the whole job again.
A week later, it was supposedly done. This time a different tech had installed the second transmission. Unfortunately, he made the same mistake as the first tech. When Jo came to pick up her car, the shop owner took her for a ride to be sure that the repairs were made to her satisfaction. It was a short drive. This time, the owner said he was going to pay for the transmission, and would even purchase one from the dealership just to be sure it wasn’t their mistake in rebuilding it. But even the dealer transmission failed to shift properly. The tranny shop was at a loss. They decided to make a few calls for some help, and that’s when my phone rang.  

Now, I’m not one to diagnose anything over the phone. I just don’t think it’s a smart way of taking care of such problems because you never quite know what you’re getting into.  But the tranny shop owner sounded desperate, and now the repair costs were coming out of his pocket. From his frantic explanations of no codes, no shift and no idea of the problem, he kind of put me on the spot … so … I suggested a computer. Heck, why not … ya’ changed the tranny three times for Pete’s sake, obviously that isn’t’ it. I probably shouldn’t have done that, but I think he wanted to try and save as much money as possible without resorting to taking it to another shop. 
Well, a new TCM didn’t work either. Now, the car is finally coming my way. Jo was a little unsure whether or not there was anyone out there who could find the problem, but her friend told her that it couldn’t hurt to let me see what I could do for her. 
When the car showed up at the shop, I took it around the block once to verify the condition and then put it up on the lift. While it was on the lift, I decided to drop it into gear and check it against the scanner.  To my surprise, it shifted perfectly. I’m not kidding … absolutely perfect.  I dropped it back on the ground, and went for a ride again. I didn’t even make it around the first corner … stuck in limp mode just as it was before. This dang thing can’t pull itself out of a pothole.
Back up on the lift, and wouldn’t ya know it, shifts perfectly … AGAIN! What’s the deal here? I did it several times just so I could be sure of the results I was getting. After a few trips, I checked the wiring to the transmission while it was on the ground. Oh, oh, the main ground to the TCM wasn’t there. How in the world was it there when it was in the air?
AH HA! It’s moving the wire! Yes, it was moving the wire alright, and a few more than just the TCM ground lead. The locator page showed the TCM ground wire was bundled with several other ground leads that were all attached to the main chassis ground, which wasn’t attached to a thing, but was dangling by the battery box.
Turns out the whole problem started when she had her battery changed at a department store repair shop, and they didn’t have the right size to fit the car. They disconnected the chassis ground wire, so the taller battery would fit.
When I told Jo what I found, the two of us pieced together the how and why it happened. Her only comment was, “Well, shift happens.”

All said and done with, the transmission shop paid for the entire repair and gave her back what she spent with them. Everyone involved was glad to have the problem solved and the car back on the road as good as new. I like this gal. She’s become a regular at the shop these days.
What a card! Always has some sarcastic comment for me, but at the same time a very understanding nature and takes life in stride. I’d love to have a couple of dozen customers just like her.
As she always tells me … “If you can’t live on the bright side of life … start polishing the dull one.”  
Scott “Gonzo” Weaver is the owner of Superior Auto Electric. He is the author of the book “Hey Look! I Found the Loose Nut”, that can be purchased online at Amazon.com or at gonzostoolbox.com 

You May Also Like

Understanding Coolants

All-season coolant used inorganic acid technology and worked great for almost 30 years.

In the 1960s, coolant was changed twice a year. In the fall, antifreeze with ethylene glycol-based coolant was put into the engine to prevent the coolant from freezing and cracking the block when a cold front hit. Often, if the engine got hot, the antifreeze would boil off. In the spring, the engine would be drained and filled with water and maybe a small can of an anti-corrosion treatment.

ECM Damage

Engineers have devised two strategies that can be called the “immune system” for the electrical system.

Voltage Drop Testing

The measurement of voltage is like the speed of the traffic.

Spark Plug Fouling

Understanding why spark plugs get dirty.

Understanding Stop/Start Charging and Starting Systems

The problem may not have been caused by a complicated reason, something simple may have caused the system not to work.

Other Posts

Power Window Regulator and Motor Service

Power windows are great as long as they roll up and down when commanded to do so.

Battery Management Means Knowing How It Ages

The battery may be fully charged, but you also need to measure how low the voltages go while the engine is cranking.

Ignition System Do’s and Don’ts

Why do ignition systems give technicians problems when diagnosing ignition-related misfires? The answer is that some technicians use tests that might give inconclusive results or do damage to the coil or drivers inside a module.

Tools To Service Serpentine Belts

Servicing the serpentine belt on some vehicles is a tough task.