Information about the Mirage CVT (Jatco CVT7 JF015E) operation, video, diagrams

[Eggman]

CVT RE0F11A JF015E CVT7 Automatic Transmission Internal & External Filter Service

[Eggman]

Gearsmagazine.com: January/February - 2019
Tales From the Bench
JF015E: Common Issues
By Jarad Warren

This article covers the Nissan version of the JF015E. Some details may not be applicable for the Mitsubishi version, such as the relearn procedure (can anyone vouch for this?) Illustrations can be found at the link. Thanks to Gears Magazine for this information.

Over the last two years, we’ve seen a big change when it comes to rebuilding the Jatco CVT. It used to be hard to find the parts needed for rebuilding this transmission; that’s no longer the case.

One other issue we’ve seen is that the dealer reman transmissions have been failing and many of the warranty claims get denied by Nissan.

If you go with a dealer reman, make sure you have the unit programmed (recommend by Nissan) and use the OE fluid. Keep all records of this for your warranty, as it may be necessary for warranty claims. If you don’t have those records, there’s a good chance Nissan will deny any warranty claims.

Some of the common issues with this transmission are pressure and performance codes, and surging and flaring as the transmission goes from low to high range.

You can rebuild this transmission and make good money doing it. There are some basic areas to cover to make a quality repair along with performing the computer relearn. We’ll break down some of the more important points, to make this transmission repair a simple service for your shop.

PUMP AND VALVE BODY
Most common issues with all Jatco CVTs center on the flow control valve. The flow valve and its bore often wear at low mileage. Make sure you pull the valve out of the pump and inspect the bore and valve (figure 1).

There are aftermarket repair kits for this valve. In addition, there are several parts vendors that are selling new pumps or remanufactured pumps that have the bore repair already done for you.

As for the valve body, always pull each valve out and clean it thoroughly. Make sure you check for bore wear and make sure the valve moves freely in the bore.

The CVT often produces fine metal particles while it’s still breaking in. This fine metal causes the valves and solenoids to wear and stick at very low mileage.

One thing to keep in mind is that Nissan knows about these problems and they’re offering the valve body with solenoids very cheaply for some models; in some cases as low as $250.

If you see wear or think you have a solenoid problem, it may be best to replace the valve body. There are some TSBs that recommend a new, updated valve body that requires special programming, so make sure you search for service bulletins when working on one of these units.

PULLEYS AND BELT
The pulley and belts are where all the force is applied. These pulleys can have as much as 850 PSI applied to them at times. You need to make sure you inspect the belt and the pulley sheaves where the belt rides. The belt and pulley sheaves may look perfect, but don’t let that fool you!

Make sure you pull the pulleys apart. Those pulleys may have damaged rollers or balls inside. The pulleys slide up and down on these balls and rollers, but their main function is to keep the pulley from spinning on the shaft. There’s a lot of force on this area and wear is common.

The secondary pulley has a reluctor for the speed sensor to read its RPM (figure 2). These reluctors are pressed onto the pulley but they often come loose. The repair is simple: Just tack-weld the reluctor in three or four spots to hold it in place.

There’s a piston in the primary pulley that’s pressed onto the pulley sheave (figure 3). The piston becomes loose and looks like it spins and wears out. The center of the piston becomes egg-shaped and creates a crossleak (figure 4). This piston needs to seal on the pulley and needs to be press-fit onto the pulley.

Don’t forget to check all bearings for pitting and rough spots.

RELEARNS
You can build or buy the best transmission in the world, but that means nothing if you don’t finish the job correctly.

The Consult III Nissan scan tool has around seven different resets for their CVTs (figure 5). Some models have more and some less. The sad part is that many aftermarket scan tools have very few or no resets at all. Just because your scan tool doesn’t have the resets doesn’t mean you can skip the relearn step.

For the best possible service, you need to make sure you have the latest updated programming installed in the computer. But reprogramming the computer doesn’t mean the resets are done.

Some of the resets must be done with the scan tool, such as the G-sensor calibration, CVT fluid deterioration, throttle body calibration, engine brake adjusts, and steering alignment (some makes and models vary). Always check the factory service information to make sure you’re resetting the system properly.

On some models, you can run the Initialize TCM and Load Calibration Data with a scan tool or by performing a manual reset, as explained in the factory service information. This allows the ECM and TCM to reset and learn to talk to each other and start with new calibration data. Then the transmission can start learning.

But wait! Here’s one of the most important relearn procedures to save for the end. Clutch Point Relearn forces the system to relearn how to shift from low range to high range. Common complaints are surging, flare shifts, and sometimes dropping into neutral. This is a must-do relearn with all rebuilt, used, or reman transmissions or valve bodies.

The procedure takes around 30 minutes and is well worth it. Let’s get started and have a stopwatch ready.

1. Start the engine and warm up the CVT fluid to 50ºC (122ºF). Confirm CVT fluid temperature by checking FLUID TEMP in the Data Monitor.
2. Turn the air conditioner and other power loads off.
3. Shift the selector lever to park.
4. Turn the engine off and wait for 5 seconds.
5. Start the engine and wait for 5 seconds.
6. Turn the engine off and wait for 30 seconds.
7. Perform step 5 and 6 two more times, for a total of three times.
8. Start the engine.
9. Shift the selector lever to drive.
10. Accelerate from 0 km/h (0 MPH) to 65 km/h (40 MPH) at low throttle (0.5/8 – 1/8 as seen on your scan tool display).
11. Coast down to 30 km/h (18 MPH) or less without using the brakes.
12. Stop the vehicle and shift the selector lever to park.
13. Turn the engine off and wait for at least 5 seconds.
14. Restart the engine.
15. Perform step 9 through 14 four more times, for a total of 5 times.
16. Shift the selector lever to drive.
17. Accelerate from 0 km/h (0 MPH) to 45 km/h (28 MPH) at low throttle (0.5/8 – 1/8 as seen on your scan tool display).
18. Stop the vehicle and shift the selector lever to park.
19. Shut the engine off for at least 5 seconds.
20. Restart the engine.
21. Perform step 16 through 20 four times, for a total of five times.
22. Drive the vehicle and check that there’s no shock while shifting.

It may be a challenge for some shops to find a safe place to perform this drive relearn, but it’s a must-do with the JF015E Jatco CVT.

To sum it all up, for a successful JF015E rebuild or repair, make sure you repair the flow control valve in the pump, inspect or replace valve body, and never shortcut the pulleys. Inspect the piston in the primary pulley and tack weld the reluctor to the secondary pulley. Don’t forget to finish the job by updating the software and performing all the resets.

Do that, and the Jatco CVT will quickly become “just another day at the transmission bench” in your shop.

I think the section on the Pump and Valve Body is noteworthy, particularly the part regarding break-in:

The CVT often produces fine metal particles while it’s still breaking in. This fine metal causes the valves and solenoids to wear and stick at very low mileage.

And also Relearns:

But wait! Here’s one of the most important relearn procedures to save for the end. Clutch Point Relearn forces the system to relearn how to shift from low range to high range. Common complaints are surging, flare shifts, and sometimes dropping into neutral. This is a must-do relearn with all rebuilt, used, or reman transmissions or valve bodies.

If anyone else has anything to add for the CVT7, please let us know.

[Eggman]

Gearsmagazine.com: December 2019
Tales From the Bench
Tips and Tricks, Jatco CVT Diagnostics
November 27, 2019
By Jarad Warren

As before, illustrations and more can be found at the link. Thanks to Gears Magazine for this information.

We’ve all felt challenged about problems with transmissions we’re unfamiliar with, and CVTs top the list. As different as these transmissions seem, there are a few “quick” tips and checks you can use to get through the diagnostics.

In this article we’ll cover the Jatco CVT transmissions, and look at some ways to make this a winner for your shop.

Finding information has been a bit of a problem but it’s getting easier every day. There are many sources out there such has webinars, bulletins, seminar books, Gears magazine articles and VTS training videos on the Jatco CVT transmissions – and that’s just from ATRA.

Nissan offers free service manuals online; just google “Nico Club Nissan service manuals”. This will bring you to the Nico Club or you can go direct to website https://www.nicoclub.com/nissan-service-manuals.

These factory manuals are very useful for looking up codes and information. Once you select the vehicle you’re working on you’ll see a long list of PDF files. The transmission manual is labeled “TM”. One of the best parts of a factory manual is that it shows what conditions will set a code. In some cases it’ll even show you the exact voltage that triggers the code.

The system description section shows how the system works and is great for understanding transmission diagnostics. To break it down further, the control system section tells you about each input and output that is used to control the CVT transmission.

Like so many other manufacturers, you might have a transmission problem due to low battery voltage or DTCs from other systems; about 60% of ATRA calls I field on these transmissions wind up being due to a bad battery or problem in another system so make sure you do a battery test and check the other systems for codes before doing any work on the transmissions. Common problems I see are with ABS codes and wheel speed sensors.

The manual will usually have a list of all the factory PIDs and what they mean. The descriptions are a bit tricky though so take your time in understanding their meaning. You can have something like “shifting doesn’t finish”, which actually means that it’s slipping or has a ratio code. Understand that these are Japanese translations and they don’t always use our terms and meanings. That’s ok, it’s still better than much of what’s out there. Here are a few PID descriptions that’ll help make it easier for you:

• VENG TRQ Display the engine torque recognized by TCM.
• PRI TRQ Displays the input shaft torque.
• TRQ RTO Displays the torque ratio of torque converter.
• PVING VOLT Displays the battery voltage to the TCM.
• ISOLT1 Displays the command current from the TCM to the torque converter clutch solenoid.
• ISOLT2 Displays the command current from the TCM to the line pressure solenoid.
• SOLMON1 Monitors the current from the TCM to the torque converter clutch solenoid.
• SOLMON2 Monitors the current from the TCM to the line pressure solenoid.
• ENGBRKLVL Displays the setting of engine brake adjust in “Work Support mode”

One thing nice with all the PIDs is they have a check system, kind of like a Dodge 48RE governor sensor. There may be a primary and/or secondary pressure sensor on many of the Jatco CVTs. Some models just use one sensor.

On the scan tool in the data section most scanners have a PID called ISOLT1 which is the TCC solenoid. Displayed is the commanded amps out of the TCM. The TCM makes sure there are no issues with wiring or the solenoid by monitoring the amps in the circuit. The PID is Solenoid Monitor 1.

In figure 1 on the top left you have the TCC solenoid amps (ISOLT 1) and to the right is monitoring the amps on TCC solenoid. As you can see the amps graphed out are the same in both pictures. This is a correct reading; you want the graphs the same and the amps should be very close at all times.

Still with figure 1 bottom left is primary pressure solenoid (ISOLT 2) amps. This is what the TCM puts out to the solenoid. To the right is Solenoid monitor 2. These should always be the same amps.

You’re likely to get a car in that feels like it is starting in the wrong gear, no engine response and loss of power. One quick and easy way of finding what’s wrong is to graph out VDC_ON, TCS_ON, ABS_ON and ACC_ON (Figure 2). All these PIDs should stay off, if they don’t then there is a code in the system. Many times, wheel speed sensor cause ABS and traction control to cut power to the engine.

Speed sensor are always a main input to the TCM for shift feel and ratio change. I feel it is always best to graph them out to compare. One nice thing Nissan did was to have two pids for each sensor. One pid for the speed sensor and the other is what the TCM is seeing.

The VSP Sensor is from the secondary pulley on most units (figure 3). ESTM VSP SIG is estimated vehicle speed sensor, it uses the ABS wheel speed signals as a back up signal. VEHICLE SPEED is coming from the ABS module. So when diagnosing speed sensors look at all three they should be matching. Be careful here, some scan tools report from the wrong sensor for VSS so, here again, check the vehicle speed in ALL the modules. Same thing with temperature readings some have a temp gun handy as a backup.

Remember to check for TSBs on every car you work on. Here is a free website that that is loaded with information: http://www.bbbind.com/tsb-and-wiring-diagrams-login/

You’ll have to sign up for it but it’s free and never sends out junk emails.

While we’re at it, this website is great for looking up recalls that might affect your work. Not to mention, what a service it is for your customer. https://www.nhtsa.gov/recalls.

There’s another website I’d like to share from OEM1STOP. It’s great for looking up programming and updates. https://oem1stop.com/

Diagnosing problems and failures are easier once you develop a plan. When you stick to the basics, you’ll usually find it.

Some links from the article:

Nico Club Nissan service manuals

BBB Industries

As of January 31st, 2020, the TSB & Wiring Diagram Database is no longer a service offered by BBB Industries. We apologize for the inconvenience.

OEM1Stop TechInfo Site

[Fummins]

Found this info for the Spark cvt. It looks like the case is different. The spark has transmission cooler lines secured to the case by studs and nuts, where the Mirage has the plate cooler and no provisions in the case for any studs. But it looks like you may be able to put a Mirage plate style cooler on the Spark cvt if you remove the studs?