A 2000 Mercury Grand Marquis with a 4.6L engine using a 4R70W transmission is at a general-repair shop for weeks. The problem is an intermittent engine surge on top of the 1-2 shift when hot. The perception is an engine problem. Eventually, the idea of the converter clutch coming on was being considered. Without much testing, the valve body and solenoids were replaced yet the problem persisted.
The vehicle is a 2012 GMC Acadia with a 6T70 that has 85,000 miles on it. It comes to us from a dealer, and it belongs to a dealer employee’s relative. What difference does who owns it make? Bear with me, it all comes together to create a nightmare.
Imagine with me for a moment that you and your team are working together to build a project vehicle. Because of scheduling challenges, each of you has to take separate turns doing the work. When your turn arrives, you enter the workspace to find all the parts you’ll need. It’s obvious something has been done, but it’s not at all clear how far and where your predecessor left off. You spend the first several minutes of your time figuring out what’s been done and then get to work.
In This Issue
Dodge/Jeep 42RLE: Multiple Solenoid Circuit and Pressure Switch Faults
Honda, no reverse
Ford 500 AF21/TF-81SC, no engagement
This article is about a customer who believed his car not starting related to his under-hood encounter with a strange critter. After chasing off his uninvited guest and making a visual inspection, the customer had the car towed to his Toyota dealer and explained that the critter was somehow responsible for the problem with his car.
A Nissan or Infiniti vehicle using the RE5R05A transmission may come into the shop with a no-move complaint. Or, a unit still under your warranty comes back with a no-move condition. And worse yet, you take it apart and see nothing wrong. The transmission is rebuilt that includes changing the torque converter and valve body as an attempt to fix the no-move problem. The unit goes back into the vehicle and still no movement. Could it be a bad TCM?
Notwithstanding the complex inner workings of the units repaired every day by retail repair shops, there’s likely nothing more complex for a shop owner to understand than profiting from the warranty offered on transmissions and other powertrain rebuilds. If you have a Ph.D. in statistical analysis, you may be slightly ahead of the rest of us, but this is one of those areas where the science melds with the arts of experience and knowledge.
About a month ago a customer came into our shop with a 2008 Chrysler Town & Country equipped with a 4.0 liter V6 engine and a 62TE transmission. He was complaining that it had a whining noise, and sometimes it would not shift and seemed to stay in the same gear. When the vehicle was hooked to the scan tool it had a code for the overdrive solenoid control circuit (P0760). The fluid was at the correct level and smelled like normal fluid; however, it was dark purple indicating possible metal contamination.
Chippy Transmission Service in Morgantown, W.Va., was founded by a man named Gay Chipps who was called Chippy. His son’s nickname was Chipper, but after a while, he was called Chippy too.
Why is it so hard to get people who are supposed to be taking in facts, sorting them out, and returning useful information, to listen? There are any number of reasons ranging from lack of proper training to thinking they know more about the issue than the person explaining it to them, to bad attitude, to burnout, to over inflated ego, to daydreaming, to pretending to understand when they really don’t. You name it and you’ll probably be right.
The MP3023 is an active automatic transfer case that is found in a wide variety of vehicles. This unit will be found in GM trucks 2007-13, Jeep Grand Cherokees 2011-19, and in Dodge Durangos 2010-up. We will be discussing the Jeep version here, which has very sophisticated control electronics. The transfer cases are basically all the same across the product line, but there are considerable variations in the electronics, which will make diagnostics outside of the transfer case a learning experience.