ATRA WEBINAR Chrysler CVT-2 Introduction

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1 ATRA WEBINAR Chrysler CVT-2 Introduction Sponsored By: Presented by: Steve Garrett ATRA

2 Today s Presentation Sponsored By:

3 Connections Handout Questions Survey

4 Thanks A special thanks to the staff at Chrysler Training group for help with this presentation.

5 CVT Compared to a Typical Transmission Internal combustion engines are most efficient within a very narrow RPM window. The range for power is typically at the upper RPM levels Best fuel economy is typically at the lower RPM levels The window for best economy and the lowest emissions is typically less than 1000 RPM Varied ratios available with a CVT meets the best of all worlds, emissions, power, economy

6 CVT2 Advantage of the CVT over Stepped Shifting Units The CVT (by use of a variable pulley set) Transaxle allows for maximum driving force and performance when compared to a conventional stepped shifting transmission. The typical savings in fuel economy is 17%. This is because the CVT unit keeps a study engine torque and output without having rapid fluctuations of engine rpm while gaining speed.

7 CVT2

8 CHRYSLER CVT 2 JATCO

9 CHRYSLER CVT 2 1. Line Pressure 2. TCC Release 3. Primary Variator 4. Forward Clutch 5. TCC Apply 6. Input Speed Sensor 7. Water-to-Oil cooler 8. Pass-Through Electrical Connector

10 CHRYSLER CVT 2 9. Secondary Variator

11 10. Reverse Clutch 11. Trans Range Sensor 12. Output Speed Sensor CHRYSLER CVT 2

The position of the pulleys is monitored and controlled

12 Introduction CVT2 The Chrysler CVT belt is used to PUSH the driven pulley driving the final drive/output. The position of the pulleys is monitored and controlled with the use of a valve body, solenoids and pressure sensors. AWD 4x4

CVT2 Squished Design Converter The Chrysler CVT uses a lock up torque converter that during idle and acceleration from a stop, multiplies torque through about 12 mph and then fully locks

13 CVT2 Squished Design Converter The Chrysler CVT uses a lock up torque converter that during idle and acceleration from a stop, multiplies torque through about 12 mph and then fully locks up driving the input to the pulleys. This design allows optimal driving force in response to the accelerator pedal operation. This torque converter is called a squished design. Pump Drive

14 BASIC CVT OPERATION

Variator System The heart of the CVT is the variator system (belt and pulley systems). It consists of a pair of pulleys (primary and secondary) with variable operating diameters and a steel push belt.

15 Variator System The heart of the CVT is the variator system (belt and pulley systems). It consists of a pair of pulleys (primary and secondary) with variable operating diameters and a steel push belt. The system relies on friction and pressure to transmit torque between the pulleys. Pulleys Each pulley set consists of two sheaves, one fixed and one floating. A fluid chamber and piston are part of the floating sheaves. The chamber operates the sheaves on their axis by way of balls and splines when hydraulic pressure is applied. Sealed Bearings have a High Failure rate. Surface Of Pulleys Should Be Dull Scotch Brite If Necessary Belt Available From Push-Belt A

pulley. Thin steel bands form the main structure of the belt. The bands consist of 12 steel layers, fitted closely together, one set on each side.

16 Variator System The Push-Belt consists of two sets of metal bands and approximately 400 wedge-shaped steel segments. The belt is considered a push-belt because the compressed segments act as a solid column, transferring torque from the primary to the secondary pulley. Thin steel bands form the main structure of the belt. The bands consist of 12 steel layers, fitted closely together, one set on each side. The bands and segments have an equal role in transferring torque between the pulleys. Edges of the belt are serrated, this aids in torque transfer. Commonly known as peaks and valleys. V

17 120K fluid service (Normal) 60K (Severe) Fluid: Mopar CVTF+4 Fluid (Green Color) Fluid and Filter Change: 7.0L (14.8 pts.) Overhaul with Converter: 8.1L (17.1 pts.) Servicing and Fluid Recommendations AA 1 qt AA 5gal

18 Checking Oil Level Checking the oil level requires Miller Tool 9336A. There is no dipstick on this unit. Fluid temperature must be monitored while testing oil level (use of scan tool). 1: Verify that the vehicle is parked on level Ground 2: Remove the dipstick cap 3: Secure parking brake and let idle with selector in P position. 4: Shift through modes keeping vehicle stationary and engine idling. 5: With transmission warm, wait 2 or more minutes and check the oil level with engine running.

19 Checking Fluid Level Miller Tool 9336A Note: The dipstick has indicator marks every 10 mm starting from the tip. The dipstick WILL protrude from the fill tube when installed!

20 Checking Oil Level Monitor Fluid Temperature Scan Tool Data While Filling

21 CVT uses both a oil to air cooler and a air to air cooler

22 Suspect Bypass valve Problems when: Overheat Condition is Present Lack of lube Issue is present Temp sensor DTC s are set System uses a cooler pressure bypass valve set at 55 psi, allows lube flow cold and when a restriction is present

Servicing and Fluid Recommendations The CVT does use a special blend of fluid. It is IMPORTANT not to mix blends and when topping off. If improper fluid is used, belt damage will occur.

23 Servicing and Fluid Recommendations The CVT does use a special blend of fluid. It is IMPORTANT not to mix blends and when topping off. If improper fluid is used, belt damage will occur. Follow the check procedure to assure the level is set properly to prevent foaming of the oil. Both under fill and over fill will cause foaming. Part Numbers: Pan Gasket: AA Oil Strainer: AA Pan bolts and Filter bolts torque: 8 Nm (70 in.lbs.) A

24 Servicing and Fluid Recommendations Note: There are two alignment pins in the case to assure pan and gasket line up correctly! Pan bolts and Filter bolts torque: 8 Nm (70 in.lbs.)

Pressure Testing and Specifications Warning!

pressures than most standard automatic transaxles.

capacity is required to take measurements.

25 Pressure Testing and Specifications Warning! High pressure unit The CVT uses considerably higher pressures than most standard automatic transaxles. A pressure gauge with a MINIMUM 7000 Kpa (1000 psi) capacity is required to take measurements. Lower pressure rated gauges will be damaged when testing! 2000 PSI Gauge Miller Tool Miller Tool

26 Pump can develop pressures in excess of 1000 PSI (6.9 Mpa) High pressure is required to prevent belt slippage and damage

27 Pressure Testing and Specifications The pressure taps are located in 3 areas of the transaxle. Certain diagnostic situations may require knowing the pressure at these various locations. ALWAYS USE CARE when doing pressure testing.

28 Pressure Testing and Specifications

29 CVT 2 Planetaries Planetary is Used to provide Reverse. The Reverse clutch Holds the Carrier to provide Reverse Rotation Pulley ratio is Locked in Reverse to Prevent overacceleration

30 Applied in Forward

32 Idler Final drive Overall Low High

33 CHRYSLER CVT 2 Depending on the application, the variator system ratio will pass through one of two final drive ratios: CVT2/CVT2A= 6.10:1 CVT2L= 8.14:1 TCM can Vary ratio for the variators from to.394-1

34 Ratio Control System Stepper motor works in conjunction with the ratio control Valve to control the primary pulley ratio The stepper motor/ratio control valve also controls the secondary valve Secondary pulley ratio

35 CVT 2 Ratio Control System

36 RATIO HOLD MODE

37 LOW TO HIGH RATIO

38 HIGH TO LOW RATIO

39 HydraulicOperation The oil pump is capable of producing system fluid pressures in excess of 6.9 MPa (1000 PSI). This high pressure is reduced by the valve body pressure regulator to supply the various systems. Operation of the CVT transaxle requires four levels of fluid pressure. *The primary and secondary pulleys require the highest pressure (up to 6.0 MPa (870 PSI)) to provide the necessary clamping force for the steel push-belt. *The second level of fluid pressure (up to 1.5 MPa (218 PSI)) is required for forward and reverse clutch operation. *The third level of fluid pressure (up to 1.0 MPa (145 PSI)) is required for TCC application. *Finally, the remaining fluid pressure (up to 0.4 MPa (60 PSI)) is used for transaxle lubrication and the fluid cooler circuits.

40 1 Secondary Pulley Control 2 Clutch Reducing Regulator Valve 3 Lockup Control 4 Select Switch Valve 5 Select Control Valve VALVE BODY ID

41 6 Solenoid Regulator Valve VALVE BODY ID

42 1 Secondary Pulley Regulator 2 Pressure Regulator 1 3 Pressure Regulator 2 4 TCC Regulator Valve 5 Manual Valve VALVE BODY ID

43 CVT 2 Valve function Line Pressure Regulator Valve The line pressure regulator valve provides supply pressure to the ratio control valve, secondary valve, and down stream for clutch regulation. Circuit pressures for the primary and secondary pulleys range from 0.5 to 6 MPa (72 to 870 PSI). Ratio Control Valve The ratio control valve is a spool valve that controls the variator ratio by controlling fluid flow into and out of the primary pulley. Secondary Valve The secondary valve is a spool valve that controls the secondary pulley pressure and the variator system clamp force.

44 CVT 2 Valve function Clutch Pressure Regulator Valve This valve provides the supply pressure necessary for the forward and reverse clutches, and down stream for TCC regulation. Circuit pressures for the forward and reverse clutches range from 0.1 to 1.5 MPa ( PSI). Manual Valve The manual valve is a spool valve that directs fluid to and away from the forward and reverse clutches based on shift lever position. Select Control Valve Adjusts the forward and reverse clutch pressures TCC Regulator Valve The TCC regulator valve provides supply pressure necessary for the TCC and lube/cooler circuits. Circuit pressures range from 0.0 to 1.0 MPa (0.0 to 145 PSI). Lock-up Control Valve Alternates torque converter clutch apply and release pressures.

45 CVT 2 system component function Secondary Pressure VFS The secondary pressure VFS controls secondary valve position by applying or removing hydraulic pressure, overcoming valve spring pressure. This action regulates clamp force on the variator system. LPVFS The LP VFS applies pressure to the end of the pressure regulator valve, overcoming spring pressure, to modulate line pressure available to the primary pulley and the secondary valve. Lock-up/Select Switch Solenoid The lock-up/select switch solenoid controls the select switch spool valve. TCC Solenoid VFS The TCC solenoid controls the lock up control spool valve and regulates forward and reverse clutch pressures. Select Switch Valve The select switch valve is a spool valve that is controlled by the lockup/select switch solenoid. It diverts fluid between the lock-up and select control valves.

46 Screens and Balls

1 TCC Lockup/Select Switch Solenoid 2 TCC Control Solenoid 3 Secondary Pressure Solenoid 4 Line Pressure Solenoid 5 Primary Pressure Sensor 6

47 1 TCC Lockup/Select Switch Solenoid 2 TCC Control Solenoid 3 Secondary Pressure Solenoid 4 Line Pressure Solenoid 5 Primary Pressure Sensor 6 Secondary Pressure Sensor 7 Stepper Motor 8 Ratio Control Valve 9 Ratio Control Link 10 ROM 11 Transmission Temperature Sensor VALVE BODY ELECTRICAL

48 PIN ID PIN MEASUREMENTS

49 CVT 2 Inputs Ranger sensor Primary Pulley Input Speed Sensor Secondary Pulley Output Speed Sensor Pressure Sensors Transmission Temp Sensor Auto Stick Engine Torque Brake Switch ABS Status System Voltage Engine RPM APP CTS VSS Ign switch position A/C request

50 If you install a new TCM, a DTC P1679 calibration not learned will set, which will also require a recalibration using a scan tool

51 CVT2 TCM

52 TCM Replacement CVT TCM Replacement The CVT has a coded ROM chip in-harness at production. This chip has values that are unique to each transaxle (2.0LPM/2.4LPM& MK/2.4L4x4 Jeep Variant). Essentially, this chip tells the TCM what type of CVT it is controlling. When the ignition key is turned on the first time at production, the TCM learns the values stored in the chip as well as vehicle configuration information (engine, tire size, if ABS, etc.) from the BUS. TCM replacement requires a flash in service. One controller part number will be provided for service. This supplied controller is generic, and has minimal functionality to provide the MIL, power, and ground to facilitate the flash. The vehicle Is not drivable until the flash is performed. The TCM has the ability to detect a CVT or TCM replacement. If a controller is replaced with one from another working vehicle, or a new CVT is installed, a mismatch P-Code is set, the MIL is illuminated, and the transaxle is placed in default/safe mode to protect the CVT hardware. The SCAN tool must be used to clear TCM memory of previously learned calibration values

53 TCM Replacement Four TCM Replacement Scenarios: New CVT & New TCM: Normal Variant Coding Process (Ignition key On Calibration Values Learned) & Service Flash New CVT & Old TCM P-Code sets & MIL illuminated Calibration Value Renewal Process (Clear TCM memory w/scan Tool, then Ignition key Off, then Ignition key On Calibration Values Learned) Old CVT & New TCM Normal Variant Coding Process (Ignition key On Calibration Values Learned) & Service Flash Old CVT & Used TCM from other vehicle Not advised because it disables another customer s vehicle P-Code sets & MIL illuminated Calibration Value Renewal Process (Scan Tool) must be performed before moving the vehicle.

54 DTC s Chrysler CVT2

56 Today s Presentation Sponsored By: THANK YOU

57 Questions Survey Thanks For Attending, See you during our Next ATRA webinar Thanks to our supplier for the support

Not Just Another. Apair of new transmissions LET'S PLAY BALL. by Lance Wiggins members.atra.com

Not Just Another. Apair of new transmissions LET'S PLAY BALL. by Lance Wiggins members.atra.com Not Just Another CVT LET'S PLAY BALL Not Just Another CVT by Lance Wiggins members.atra.com Apair of new transmissions were introduced in the 2014 Chevrolet Spark (C Body): The CVT-7 and 1ET35. We ll take