Another Transmission Mutation – Part 2 - Transmission Digest

Another Transmission Mutation – Part 2

I'm working on a 1997 Chevy truck that has an "intermittent transmission," as the owner puts it. He goes on to explain, "It works fine most of the time but when it gets into its spell of acting up, it seems like all I get is one or two gears of bad gas mileage and no power."

Another Transmission Mutation – Part 2

Technically Speaking

Subject: Locations and identification of components
Unit: A4CF2
Vehicle Applications: 2006-up Kia Spectra, 2007-up Hyundai Elantra
Essential Reading: Rebuilder, Diagnostician
Author: Wayne Colonna, ATSG, Transmission Digest Technical Editor

Technically Speaking

  • Subject: Locations and identification of components
  • Unit: A4CF2
  • Vehicle Applications: 2006-up Kia Spectra, 2007-up Hyundai Elantra
  • Essential Reading: Rebuilder, Diagnostician
  • Author: Wayne Colonna, ATSG, Transmission Digest Technical Editor

Part 1 of this article, in the February issue, introduced to you a transmission called the A4CF2 used in Hyundai and Kia vehicles. After writing Part 1, I had time to go through the valve body to do some circuit tracing so I could provide you with valve-body information that would include locations and identification of small parts and the valves.

While going through this process I discovered that the solenoid identification provided in Part 1 was not correct. The information came from an OE source that I relied on to be correct but in fact was wrong. As I delved into this project I soon learned that OE has this information right in some places yet wrong in others, and I happened to select the one that was wrong. Isn’t that the way it goes?

I also discovered that OE provides two different names for one solenoid, which can be a bit confusing. To sort all this out for myself and you, the reader, Figure 1 shows the correct solenoid locations along with their names and functions, and Figure 2 has the correct case-connector terminal identification.

Starting from the left side of the solenoid assembly, the first solenoid you will see is called PCSV-A, also referred to as SCSV-B; this solenoid applies and releases the overdrive clutch and the low/reverse brake. The second solenoid is called an on-off solenoid as well as SCSV-A, and it operates an OD-L/R switch valve in the valve body, allowing the first solenoid to operate these two different clutch assemblies. The third solenoid, called PCSV-D and TCC-SV, operates converter-clutch apply and release. The fourth solenoid is PCSV-C/SCSV-D, which operates the underdrive clutch. The last solenoid is called both PCSV-B and SCSV-C, controlling the apply and release of the 2/4 brake clutch assembly.

Quite confusing, isn’t it? And then to find OE information that contradicts the company’s identification and location could drive one crazy, especially if you need to replace a specific solenoid.

Another area that is lacking regarding this transmission is information about the valve body itself. Figures 3 through 8 provide all the small-part locations and identification; figures 9 through 12 identify all the valves and their locations.

Figure 13 provides a simple black-and-white hydraulic diagram for the purpose of showing the arrangement of all these parts in the hydraulic operation of this transmission.

All in all it is a simple transmission. If you have an ATSG F4A41 Techtran Manual for Mitsubishi and an A4CF2 sitting on the bench, you will see that the internal components are nearly identical. Put this together with parts 1 and 2 of this article and you will have plenty of information needed to work on this little guy.

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