MAJOR COMPONENTS
This transaxle has the following major components
- Case with torque converter housing
- Two drive clutches: Direct clutch Overdrive (O/D)
- Four brake clutches: Forward clutch Low one-way clutch Intermediate clutch
- Three planetary gearsets: Front Center Rear
- Drive chain and sprockets
- Final drive planetary gearset and differential assembly
- Pump and filter assembly
- Main control: Valve body assembly Solenoid body assembly
Scheme 471
Scheme 472
GEAR RATIOS
This transaxle has 6 forward speeds and reverse.
Gear Ratio Chart
| Gear | Ratio |
|---|---|
| 1st/low | 4.584:1 |
| 2nd | 2.964:1 |
| 3rd | 1.912:1 |
| 4th | 1.446:1 |
| 5th | 1:1 |
| 6th | 0.746:1 |
| Reverse | 2.94:1 |
GEAR RATIO CHART
Upshifts
Upshifting is controlled by the PCM. The PCM receives inputs from various engine or vehicle sensors and driver demands to control shift scheduling, shift feel and torque converter clutch (TCC) operation.
The PCM has an adaptive learn strategy to electronically control the transaxle which will automatically adjust the shift feel through the life of the vehicle. The first few hundred miles of operation of the transaxle may have abrupt shifting. This is a normal operation. To reset the adaptive shift pressure strategy, use the scan tool tc clear the transmission keep alive memory tables.
Downshifts
Under certain conditions, the transaxle will downshift automatically to a lower gear range (without moving the selector lever). There are 3 categories of automatic downshifts: coastdown, torque demand and forced or kick-down shifts.
Coastdown
The coastdown downshift occurs when the vehicle is coasting down to a stop.
Kickdown
For maximum acceleration, the driver can force a downshift by pressing the accelerator pedal to the floor. A forced downshift into a lower gear is possible below calibrated speeds. Specifications for downshift speeds are subject to variations due to tire size, engine and transaxle calibration requirements.
Planetary Gearset
This transaxle has 3 planetary gearsets to provide operation in reverse and 6 forward speeds.
The gearsets are comprised of the following components
- Front planetary sun gear (part of the front sun gear and shell assembly)
- Front planetary carrier
- Front planetary ring gear
- Center planetary sun gear
- Center planetary carrier
- Center planetary ring gear
- Rear planetary ring gear
- Rear planetary carrier
- Rear planetary sun gear and shell assembly
The front planetary sun gear is splined to the forward (1, 2, 3, 4) clutch and is held stationary in 1st, 2nd, 3rd and 4th gear.
The front planetary carrier is splined to the rear planetary ring gear and transfers power from the rear planetary gearset to the front planetary gearset in 2nd, 3rd, 5th and 6th gear and reverse. The front planetary carrier is splined to the drive chain drive sprocket. The front planetary carrier is the output component for the planetary gearset.
The front planetary ring gear is splined to the center planetary carrier and transfers power from the center planetary gearset to the front planetary gearset in 1st, 2nd, 3rd and 4th gear.
The center planetary sun gear is splined to the input shaft and is used as input to the planetary gearsets in 1st, 2nd, 3rd and 4th gear.
The center planetary ring gear is splined to the rear planetary carrier and transfers power from the center planetary gearset to the rear planetary gearset in 3rd gear, from the rear planetary gearset to the center planetary gearset in 4th gear and is held stationary by the low one way clutch (OWC) and low/reverse clutch in 1st gear and reverse.
The rear planetary carrier is splined to the overdrive (OD) (4, 5, 6) clutch hub and transfers power from the input shaft to the rear planetary carrier in 4th, 5th and 6th gear.
The rear planetary sun gear and shell assembly is splined to both the intermediate (2, 6) clutch and the direct (3, 5, R) clutch. The rear planetary sun gear and shell assembly is held stationary by the intermediate (2, 6) clutch in 2nd and 6th gear and is driven by the direct (3, 5, R) clutch in 3rd and 5th gear and reverse.
Scheme 473
Input Shaft
The input shaft is part of the direct/OD clutch assembly and is splined to the torque converter turbine and the center planetary sun gear. The input shaft transfers power from the torque converter to the rear planetary gear through the center planetary sun gear and the direct (3, 5, R) and OD (4, 5, 6) clutches.
Scheme 474
Scheme 475
Front Planetary Carrier Hub (Output Hub)
The front planetary carrier hub/park gear is splined to the front planetary carrier and the drive chain drive sprocket. This allows torque to be transferred from the planetary gearset to the final drive gearset.
Scheme 476
Final Drive Chain, Sprockets and Planetary Gearset
The final drive consists of a drive chain and sprockets and a planetary gearset and differential assembly. The drive chain and sprockets transfer torque from the front planetary carrier hub to the differential assembly that has a planetary gearset integrated into it for final drive torque multiplication.
The final drive consists of the following components
- Drive sprocket
- Drive chain
- Driven sprocket
- Final drive sun gear
- Final drive ring gear
- Final drive planetary carrier and differential assembly
Scheme 477
Scheme 478
Differential
The differential allows the halfshafts and wheels to rotate at different speeds during cornering and transfers power to the power transfer unit (PTU) for all wheel drive (AWD) vehicles.
The differential assembly consists of the following components
- Differential case (part of the final drive carrier)
- Two pinion gears supported by a pinion shaft
- Two side gears supported by the differential case and halfshafts
When driving in a straight line, both front wheels rotate at relatively the same speed. This means both side gears are rotating at the same speed, as well, while both pinion gears revolve (but do not rotate) with the side gears. During cornering, the wheel on the outside of the turn is forced to rotate faster than the wheel on the inside of the turn. Since the side gears must now rotate at different speeds, the pinion gears rotate on the pinion shaft allowing the drive axles to rotate at different speeds while still transferring output torque.
Scheme 479
Direct (3, 5, R) Clutch
The direct clutch is a drive clutch that transfers power from the direct/O/D clutch hub assembly to the rear planetary sun gear and shell assembly. The direct clutch is applied in 3rd and 5th gear and reverse.
Hydraulic pressure from the regulator valve in the valve body pushes the direct clutch piston against the direct clutch pack to apply the clutch. The input shaft and direct/O/D clutch hub assembly transfers torque to the rear planetary sun gear and shell assembly as a result of the clutch being applied.
Scheme 480
Scheme 481
Scheme 482
O/D (4, 5, 6) Clutch
The O/D clutch is a drive clutch that transfers power from the direct/O/D clutch hub assembly to the rear planetary carrier. The O/D clutch is applied in 4th, 5th and 6th gear.
Hydraulic pressure from the regulator valve in the valve body pushes the O/D clutch piston against the O/D clutch pack to apply the clutch. The input shaft and direct/O/D clutch hub assembly transfers torque to the rear planetary carrier as a result of the clutch being applied.
Scheme 483
Scheme 484
Forward (1, 2, 3, 4) Clutch
The forward clutch is a brake clutch that holds the front sun gear and shell assembly. The forward clutch is applied in 1st, 2nd, 3rd and 4th gear.
Hydraulic pressure from the regulator valve in the valve body pushes the forward clutch piston against the forward clutch pack to apply the clutch. The front sun gear and shell assembly is held stationary to the transaxle case as a result of the clutch being applied.
Scheme 485
Scheme 486
Low/Reverse Clutch
The low/reverse clutch is a brake clutch that holds the low one way clutch (OWC) which is splined to the rear planetary carrier. The low/reverse clutch is applied in manual LOW, REVERSE and 1st gear up to 6 km/h (4 mph).
Hydraulic pressure from the regulator valve in the valve body pushes the low/reverse clutch piston against the low/reverse clutch pack to apply the clutch. The rear planetary carrier is held stationary to the transaxle case as a result of the clutch being applied.
Scheme 487
Scheme 488
Intermediate (2, 6) Clutch
The intermediate clutch is a brake clutch that holds the rear planetary sun gear and shell assembly. The intermediate clutch is applied in 2nd and 6th gear.
Hydraulic pressure from the regulator valve in the valve body pushes the intermediate clutch piston against the intermediate clutch pack to apply the clutch. The low OWC works as a pressure plate for the intermediate (2, 6) clutch. The rear planetary sun gear and shell assembly is held stationary to the transaxle case as a result of the clutch being applied.
Scheme 489
Scheme 490
Low One Way Clutch (OWC) Cutaway View
The low OWC is a brake clutch that holds the rear planetary carrier in one direction and allows it to freewheel in the opposite direction which eliminates engine braking in 1st gear when the transaxle is in DRIVE. The low OWC is also the pressure plate for the intermediate (2, 6) clutch.
Scheme 491
External Sealing
The torque converter housing has a lip-type seal that seals the torque converter hub. The pump assembly seals to the torque converter housing with a rubber seal. The manual shaft and halfshafts also use lip-type seals. All wheel drive (AWD) vehicles do not use a RH halfshaft seal, the transaxle is sealed by the power transfer unit (PTU) on the RH side.
The torque converter housing is sealed to the transaxle case with silicone sealant.
The main control cover is sealed to the transaxle case with silicone sealant and seals to the solenoid body with a reusable rubber gasket. The turbine shaft speed (TSS) sensor is sealed to the transaxle case with an O-ring seal.
The line pressure tap plug and transmission fluid drain plug have pipe threads and seal when tightened to specification.
The transaxle fluid filler tube is sealed to the torque converter housing with an O-ring seal.
Scheme 492
Scheme 493
The No. 4 thrust bearing is part of the rear planetary carrier assembly. The No. 9 thrust bearing is part of the front planetary carrier assembly. The No. 14 thrust bearing is part of the differential assembly.
Park
The park gear is splined to the front planetary carrier and the drive chain drive sprocket. There are lugs around the outer diameter of the park gear to allow the park pawl to hold the park gear stationary to the transaxle case which holds the final drive assembly in place and keeps the vehicle from moving.
When the manual control lever is rotated to the PARK position, the park lock works as follows
- The transmission range (TR) sensor rotates the range detent plate which pushes the park pawl actuator rod towards the park pawl.
- The actuator rod pivots the park pawl into the lugs on the park gear, locking the gear stationary to the transaxle case.
Scheme 494
Main Control
The hydraulic system has a main control assembly. The main control assembly consists of a valve body and a solenoid body. Both the valve body and the solenoid body contain hydraulic shift valves. The solenoid body contains the shift solenoids that control the hydraulic valves. The solenoid body can be serviced as an assembly with the solenoids or the solenoids can be serviced individually. The solenoid body is controlled by the PCM. The PCM has software stored in it specific to the solenoid body currently in the transaxle, called the solenoid body strategy. A new solenoid body strategy must be downloaded into the PCM anytime a new solenoid body is installed.
The pump assembly contains the main pressure regulator valve assembly and the torque converter clutch (TCC) control valve assembly.
Scheme 495
Scheme 496
Scheme 497
Scheme 498
Scheme 499
Scheme 500
| Circuit Name | Description |
|---|---|
| BYPASS | Pressure from the main pressure regulator valve to the pump assembly suction circuit for line pressure control. |
| C1234 | Regulated line pressure from the 1234 regulator valve supplied to the forward (1, 2, 3, 4) clutch to apply the clutch. |
| C1234 FDBK | C1234 pressure from the 1234 latch valve supplied to the 1234 regulator valve to oppose movement of the valve from VBS C1234 pressure during forward (1, 2, 3, 4) clutch application |
| C35R | Regulated line pressure from the 35R regulator valve supplied to the direct (3, 5, R) clutch to apply the clutch. |
| C35R FD | Line pressure from the REVERSE circuit supplied to the DRIVE 2/C35R FD shuttle valve by the clutch control bypass valve to supply the 35R regulator valve with line pressure in reverse. |
| C35R FDBK | C35R pressure from the 35R latch valve supplied to the 35R regulator valve to oppose movement of the valve from VBS C35R pressure during direct (3, 5, R) clutch application. |
| C456 | Regulated line pressure from the low reverse/456 regulator valve directed to the O/D (4, 5, 6) clutch by the clutch control bypass valve. C456 also provides latch pressure for the clutch control bypass valve. |
| CB26 | Regulated line pressure from the 26 regulator valve to the intermediate (2, 6) clutch to apply the clutch in 2nd and 6th gear. |
| CB26 FDBK | CB26 pressure from the 26 latch valve supplied to the 26 regulator valve to oppose movement of the valve from VBS C26 pressure during intermediate (2, 6) clutch application. |
| CBR1 | Regulated line pressure from the low reverse/456 regulator valve directed to the low/reverse clutch by the clutch control bypass valve. |
| CBR1/C456 | Regulated line pressure from the low reverse/456 regulator valve to the clutch control bypass valve. |
| CBR1/C456 FDBK | CBR1/C456 pressure from the low reverse/456 latch valve supplied to the low reverse/456 regulator valve to oppose movement of the valve from VBS CBR1/456 pressure during low/reverse or O/D (4, 5, 6) clutch application. |
| COMP FD | Pressure supplied to the opposite side of the O/D (4, 5, 6) and direct (3, 5, R) clutch apply pistons to oppose centrifugal application of the clutches |
| CONV FD | Line pressure from the main pressure regulator valve supplied to the TCC control valve for TCC release. |
| COOLER FD | Return pressure from the torque converter during TCC release that is directed to the transaxle fluid cooler by the TCC control valve. |
| DRIVE | Line pressure directed to the clutch control bypass valve, 1234 regulator valve and the 26 regulator valve by the manual valve in the DRIVE position. |
| DRIVE 2 | DRIVE pressure directed to the regulator valve and the DRIVE 2/C35R FD shuttle valve by the clutch control bypass valve to supply the 35R regulator valve with line pressure in 3rd and 5th gear. |
| DRIVE 2/C35R FD | DRIVE 2 or C35R FD pressure supplied to the 35R regulator valve from the DRIVE 2/C35R FD shuttle valve during direct (3, 5, R) clutch application. |
| EXH | Fluid exhausted from the valves that drains to the sump area. |
| EXH BF | Unpressurized fluid from the manual valve that fills the unused hydraulic circuits. |
| LINE | Pressure from the pump to the control pressure regulator, solenoid regulator valve, manual valve and low reverse/456 regulator valve. Line pressure is regulated by the main pressure regulator valve. |
| LUBE | Transaxle lubrication circuit (through the input shaft) |
| ON/OFF SIG | Full solenoid output pressure from SSE to the clutch control bypass valve and the TCC regulator valve. ON/OFF SIG pressure positions the clutch control bypass valve to apply either the low/reverse clutch or the O/D (4, 5, 6) clutch. |
| REG APPLY | Regulated DRIVE 2 pressure supplied to the TCC control valve by the control pressure regulator for TCC application. |
| REVERSE | Line pressure directed to the clutch control bypass valve by the manual valve in the REVERSE position. |
| SOL FD | Regulated line pressure supplied to the shift, TCC and LPC solenoids. |
| TCC APPLY | Pressure supplied to the torque converter by the TCC control valve to apply the clutch. TCC APPLY is also the return circuit for the TCC RELEASE circuit. |
| TCC RELEASE | Pressure supplied to the torque converter by the TCC control valve to release the clutch. TCC RELEASE is also the return circuit for the TCC APPLY circuit. |
| VBS C1234 | Variable SOL FD pressure supplied to the 1234 regulator valve and 1234 latch valve by SSA to position the valves to apply the forward (1, 2, 3, 4) clutch. |
| VBS C35R | Variable SOL FD pressure supplied to the 35R regulator valve and 35R latch valve by SSB to position the valves to apply the direct (3, 5, R) clutch. |
| VBS CB26 | Variable SOL FD pressure supplied to the 26 regulator valve and 26 latch valve by SSC to position the valves to apply the intermediate (2, 6) clutch. |
| VBS CBR1/456 | Variable SOL FD pressure supplied to the low reverse/456 regulator valve and low reverse/456 latch valve by SSD to position the valves to apply the low/reverse clutch or O/D (4, 5, 6) clutch. |
| VBS LINE | Variable SOL FD pressure supplied to the main pressure regulator valve by the LPC solenoid to control line pressure. |
| VBS TCC | Variable SOL FD pressure supplied to the TCC regulator valve and TCC control valve to position the valves by the TCC solenoid to apply the TCC. |
DESCRIPTION CHART
Scheme 501
Scheme 502
Scheme 503
Scheme 504
Scheme 505
Line Pressure Hydraulic Circuits
Line pressure is controlled by the line pressure control (LPC) solenoid, which is controlled by the PCM. This effects shift feel and apply component operation.
When the engine is running, the pump supplies pressure to the main pressure regulator valve, which is controlled by the LPC solenoid. The main pressure regulator valve controls the line pressure to the LINE circuit which supplies the manual valve, solenoid regulator valve, and the control pressure regulator valve.
When the manual valve is in the reverse position, it supplies the clutch control bypass valve with line pressure to position it to supply line pressure the direct (3, 5, R) regulator valve and regulated line pressure to the low/reverse clutch to apply the clutch. When the manual valve is in the DRIVE or LOW positions it directs line pressure from the LINE circuit to the DRIVE circuit to supply the clutch control bypass valve, the forward (1, 2, 3, 4) regulator valve, intermediate (2, 6) regulator valve, TCC regulator valve and the direct (3, 5, R) clutch regulator valve with line pressure.
Scheme 506
Solenoid Hydraulic Circuits
Line pressure from the main pressure regulator valve is directed to the individual shift, TCC and LPC solenoids by the solenoid regulator valve through the SOL FD circuit. The solenoids, controlled by the PCM, direct the fluid to the valves that they control.
The LPC solenoid applies varying pressure to the main pressure regulator valve to control line pressure.
In the PARK and NEUTRAL positions, SSD applies varying pressure to the low reverse/456 regulator and latch valves through the VBS CBR1/456 hydraulic circuit to position the valves to apply the low/reverse clutch. ON/OFF SSE directs pressure to the clutch control bypass valve to position the valve to direct regulated line pressure from the low reverse/456 regulator valve to the low/reverse clutch.
Scheme 507
In the REVERSE position, SSD applies varying pressure to the low reverse/456 regulator and latch valves through the VBS CBR1/456 hydraulic circuit to position the valves to apply the low/reverse clutch. ON/OFF SSE directs pressure to the clutch control bypass valve to position the valve to direct regulated line pressure from the low reverse/456 regulator valve to the low/reverse clutch. The clutch control bypass valve also directs line pressure from the REVERSE circuit to the 35R regulator valve through the C35R FD and DRIVE 2/C35R FD circuits. SSB directs varying pressure to the 35R regulator and latch valves through the VBS C35R hydraulic circuit to apply the direct (3, 5, R) clutch.
Scheme 508
In 1st gear, SSA applies varying pressure to the 1234 clutch regulator and latch valves through the VBS C1234 hydraulic circuit to apply the forward (1, 2, 3, 4) clutch.
When vehicle speed is below 6 km/h (4 mph), or the selector lever is in the manual low position, SSD applies varying pressure to the low reverse/456 regulator and latch valves through the VBS CBR1/456 hydraulic circuit to position the valves to apply the low/reverse clutch. ON/OFF SSE directs pressure to the clutch control bypass valve to position the valve to direct regulated line pressure from the low reverse/456 regulator valve to the low/reverse clutch. As vehicle speed increases above 6 km/h (4 mph) in 1st gear, SSD removes pressure from the low reverse/456 regulator and latch valves and SSE removes pressure from the clutch control bypass valve to release the low/reverse clutch.
Scheme 509
Scheme 510
In 2nd gear, the forward (1, 2, 3, 4) clutch remains applied. SSC applies varying pressure to the 26 regulator and latch valves through the VBS CB26 hydraulic circuit to apply the intermediate (2, 6) clutch.
Scheme 511
In 3rd gear, the forward (1, 2, 3, 4) clutch remains applied. SSC releases pressure to the 26 regulator and latch valves to release the intermediate (2, 6) clutch. SSB directs pressure to the 35R regulator and latch valves through the VBS CB26 hydraulic circuit to apply the direct (3, 5, R) clutch.
Scheme 512
In 4th gear, the forward (1, 2, 3, 4) clutch remains applied. SSB releases pressure to the 35R regulator and latch valves. SSD directs pressure to the low reverse/456 regulator and latch valves through the VBS CBR1/456 hydraulic circuit. With SSE released, the clutch control bypass valve directs the regulated line pressure from the low reverse/456 regulator valve to the O/D (4, 5, 6) clutch to apply the clutch.
Scheme 513
In 5th gear, the O/D (4, 5, 6) clutch remains applied. SSA releases pressure to the 1234 regulator and latch valves to release the forward (1, 2, 3, 4) clutch. SSB directs pressure to the 35R regulator and latch valves through the VBS C35R hydraulic circuit to apply the direct (3, 5, R) clutch.
Scheme 514
In 6th gear, the O/D (4, 5, 6) clutch remains applied. SSB releases pressure to the 35R regulator and latch valves. SSC applies varying pressure to the 26 clutch regulator and latch valves through the VBS CB26 hydraulic circuit to apply the intermediate (2, 6) clutch.
The TCC can be applied in 4th, 5th, or 6th gear. To apply the TCC, the TCC solenoid applies pressure to the TCC regulator valve and the TCC control valve to position the valves to apply the clutch.
Scheme 515
During a mechanical, hydraulic or electrical failure with the manual lever in the DRIVE position, the transaxle defaults to 5th gear. When the transaxle is in 5th gear fail-safe, the PCM does not control the shift solenoids and they default to their normal state (maximum pressure, minimum pressure, On or Off). The LPC solenoid defaults to maximum pressure, SSA defaults to minimum pressure, SSB defaults to maximum pressure, SSC defaults to minimum pressure, SSD defaults to maximum pressure and the TCC solenoid defaults to minimum pressure.
With SSB applying maximum pressure to the direct (3, 5, R) regulator and latch valves, the direct (3, 5, R) clutch is applied. With SSD applying maximum pressure to the low reverse/456 regulator and latch valves with SSE in the OFF position, the overdrive (4, 5, 6) clutch is applied, providing 5th gear.
Scheme 516
Forward (1, 2, 3, 4) Clutch Hydraulic Circuits
Line pressure is supplied to the 1234 regulator valve by the manual valve in the DRIVE and LOW position. To apply the forward (1, 2, 3, 4) clutch, SSA supplies varying solenoid pressure to the 1234 regulator and latch valves. As the regulator valve moves, it supplies the forward (1, 2, 3, 4) clutch and 1234 latch valve with regulated line pressure through the C1234 circuit. The 1234 latch valve directs the regulated line pressure to the opposite side of the 1234 regulator valve through the C1234 FDBK circuit for gradual forward (1, 2, 3, 4) clutch engagement. The forward (1, 2, 3, 4) clutch is applied in 1st, 2nd, 3rd, and 4th gear and manual LOW position.
Scheme 517
When the forward (1, 2, 3, 4) clutch is released in 5th and 6th gear, solenoid pressure from SSA is removed from the 1234 regulator and latch valves which positions the valves to block line pressure and release the forward (1, 2, 3, 4) clutch. When the forward (1, 2, 3, 4) clutch is released in the PARK, REVERSE or NEUTRAL position, line pressure is not supplied to the forward (1, 2, 3, 4) regulator valve.
In the released position, exhaust backfill supplied to the 1234 regulator and latch valves by the manual valve through the EXH BF circuit is directed to the forward (1, 2, 3, 4) clutch to fill the unused circuits with unpressurized transaxle fluid.
Scheme 518
Direct (3, 5, R) Clutch Hydraulic Circuits
When the direct (3, 5, R) clutch is applied in the REVERSE position, line pressure from the manual valve is directed to the clutch control bypass valve through the REVERSE circuit. Line pressure in the REVERSE circuit positions the clutch control bypass valve and supplies line pressure to apply the direct (3, 5, R) clutch. Line pressure from the clutch control bypass valve is supplied to the 35R regulator valve through the C35R FD circuit, DRIVE 2/C35R FD shuttle ball and DRIVE 2/C35R FD circuit.
To apply the direct (3, 5, R) clutch, SSB applies varying solenoid pressure to the 35R regulator and latch valves. As the regulator valve moves, it supplies the direct (3, 5, R) clutch and 35R latch valve with regulated line pressure through the C35R circuit. The 35R latch valve directs the regulated line pressure to the opposite side of the 35R regulator valve through the C35R FDBK circuit for gradual direct (3, 5, R) clutch engagement.
Scheme 519
When the direct (3, 5, R) clutch is applied in 3rd and 5th gear, line pressure from the pump is directed to the clutch control bypass valve by the manual valve through the DRIVE hydraulic circuit. The clutch control bypass valve directs the pressure to the 35R regulator valve through the TCC regulator valve, DRIVE 2 circuit, DRIVE 2/C35R FD shuttle ball and DRIVE 2/C35R FD circuit.
To apply the direct (3, 5, R) clutch, SSB applies varying solenoid pressure to the 35R regulator and latch valves. As the 35R regulator valve moves, it supplies the direct (3, 5, R) clutch and 35R latch valve with regulated line pressure through the C35R circuit. The 35R latch valve directs the regulated line pressure to the opposite side of the regulator valve through the C35R FDBK circuit for gradual direct (3, 5, R) clutch engagement.
Scheme 520
When the direct (3, 5, R) clutch is released, solenoid pressure from SSB is removed from the 35R regulator and latch valves which positions the valves to block line pressure and release the direct (3, 5, R) clutch. When the direct (3, 5, R) clutch is released in the PARK or NEUTRAL position, line pressure is not supplied to the 35R regulator valve.
Compensator feed pressure is supplied to the 35R regulator valve from the control pressure regulator through the COMP FD circuit and is supplied to the opposite side of the direct (3, 5, R) and overdrive (4, 5, 6) clutch pistons to keep the clutches from centrifugally applying. COMP FD pressure is only about 83 kPa (12 psi) and is applied through all gears. When the direct (3, 5, R) clutch is released, COMP FD is applied by the 35R regulator valve to the direct (3, 5, R) clutch to fill the unused circuits.
Scheme 521
Intermediate (2, 6) Clutch Hydraulic Circuits
Line pressure is supplied to the 26 regulator valve by the manual valve in the DRIVE and LOW positions. To apply the intermediate (2, 6) clutch, SSC supplies varying solenoid pressure to the 26 regulator and latch valves. As the 26 regulator valve moves, it supplies the intermediate (2, 6) clutch and 26 latch valve with regulated line pressure through the CB26 circuit. The 26 latch valve directs the regulated line pressure to the opposite side of the 26 regulator valve through the CB26 FDBK circuit for gradual intermediate (2, 6) clutch engagement. The intermediate (2, 6) clutch is applied in 2nd and 6th gear.
Scheme 522
When the intermediate (2, 6) clutch is released in 1st, 3rd, 4th and 5th gear and manual LOW position, solenoid pressure from SSC is removed from the 26 regulator and latch valves which positions the valves to block line pressure and release the intermediate (2, 6) clutch. When the intermediate (2, 6) clutch is released in the PARK, REVERSE or NEUTRAL position, line pressure is not supplied to the 26 regulator valve.
In the released position, exhaust backfill supplied to the 26 clutch regulator valve by the manual valve through the EXH BF circuit is directed to the intermediate (2, 6) clutch and 26 latch valve to fill the unused circuits with unpressurized transaxle fluid.
Scheme 523
Low/Reverse Clutch Hydraulic Circuits
Line pressure is supplied to the low reverse/456 regulator valve by the pump in every gear and manual lever position. To apply the low/reverse clutch, SSD supplies varying solenoid pressure to the low reverse/456 regulator and latch valves. As the low reverse/456 regulator valve moves, it supplies the clutch control bypass valve and low reverse/456 latch valve with regulated line pressure through the CBR1/C456 circuit. The low reverse/456 latch valve directs the regulated line pressure to the opposite side of the 456 regulator valve through the CBR1/C456 FDBK circuit for gradual low reverse/456 clutch engagement. The low/reverse clutch is applied in PARK, REVERSE, NEUTRAL, 1st gear below 6 km/h (4mph) and manual LOW position.
In REVERSE, both solenoid pressure from ON/OFF SSE and line pressure from the manual valve in the REVERSE circuit apply pressure to the clutch control bypass valve to position it for low/reverse clutch application. Regulated line pressure from the CBR1/C456 circuit is directed to the low/reverse clutch by the clutch control bypass valve through the CBR1 circuit to apply the low/reverse clutch.
Scheme 524
When the low/reverse clutch is applied in PARK, NEUTRAL, LOW or 1st gear below 6 km/h (4 mph), only pressure from ON/OFF SSE, positions the clutch control bypass valve. Line pressure from the REVERSE circuit is not supplied by the manual valve.
Scheme 525
When the low/reverse clutch is released in 1st gear above 6 km/h (4 mph), 2nd and 3rd gear, solenoid pressure from SSD is removed from the low reverse/456 regulator and latch valves which positions the valves to block line pressure and release the low/reverse clutch. Solenoid pressure from SSE is removed from the clutch control bypass valve to position it to apply the overdrive (4, 5, 6) clutch.
When the low/reverse clutch is released in 1st gear above 6 km/h (4 mph), 2nd and 3rd gear, exhaust backfill supplied to the low reverse/456 clutch regulator valve and the clutch control bypass valve by the manual valve through the EXH BF circuit is directed to the low reverse/456 latch valve, low/reverse clutch and overdrive (4, 5, 6) clutch to fill the unused circuits with unpressurized transaxle fluid.
When the low/reverse clutch is released in 4th, 5th and 6th gear, the low reverse/456 regulator valve supplies regulated pressure to the clutch control bypass valve through the CBR1/C456 circuit. With ON/OFF SSE in the OFF position, the regulated pressure is directed to the overdrive (4, 5, 6) clutch.
Scheme 526
Overdrive (4, 5, 6) Clutch Hydraulic Circuits
Line pressure is supplied to the low reverse/456 regulator valve by the pump in every gear and manual lever position. To apply the low/reverse clutch, SSD supplies varying solenoid pressure to the low reverse/456 regulator and latch valves. As the regulator valve moves, it supplies the clutch control bypass valve and low reverse/456 latch valve with regulated line pressure through the CBR1/C456 circuit. The low reverse/456 latch valve directs the regulated line pressure to the opposite side of the low reverse/456 regulator valve through the CBR1/C456 FDBK circuit for gradual overdrive (4, 5, 6) clutch engagement.
To apply the overdrive (4, 5, 6) clutch, the position of the clutch control bypass valve allows the regulated line pressure in the CBR1/C456 circuit to supply the C456 circuit, applying the overdrive (4, 5, 6) clutch. Clutch control bypass valve latch pressure is supplied by the C456 circuit. The overdrive (4, 5, 6) clutch is applied in 4th, 5th and 6th gear.
Scheme 527
When the overdrive (4, 5, 6) clutch is released in 1st gear above 6 km/h (4 mph), 2nd and 3rd gear, solenoid pressure from SSD is removed from the low reverse/456 regulator and latch valves which positions the valves to block line pressure and release the overdrive (4, 5, 6) clutch.
When the overdrive (4, 5, 6) clutch is released in 1st gear above 6 km/h (4 mph), 2nd and 3rd gear, exhaust backfill supplied to the low reverse/456 clutch regulator valve and the clutch control bypass valve by the manual valve through the EXH BF circuit is directed to the low reverse/456 latch valve, low/reverse clutch and overdrive (4, 5, 6) clutch to fill the unused circuits with unpressurized transaxle fluid.
When the overdrive (4, 5, 6) clutch is released in PARK, REVERSE, NEUTRAL and 1st gear below 6 km/h (4 mph), the low reverse/456 regulator valve supplies regulated pressure to the clutch control bypass valve through the CBR1/C456 circuit. With ON/OFF SSE in the ON position, the regulated pressure is directed to the low/reverse clutch.
Scheme 528
Electronic Ignition (EI)
The EI system consists of a PCM, a crankshaft position (CKP) sensor and ignition coils. The CKP sends a crankshaft position signal to the PCM. The PCM then sends the appropriate ignition signal to the ignition coils. The PCM also uses this signal as well as wide open throttle (WOT) shift control and electronic pressure control.
Accelerator Pedal Position (APP)
The APP sensor is mounted on the accelerator pedal. The APP detects the position of the accelerator pedal and inputs this information as a voltage to the PCM. The PCM uses APP sensor information to aid in determining line pressure, shift scheduling and TCC operation. Failure of this sensor will cause the transaxle to operate at higher line pressure to avoid damage to the transaxle. This higher line pressure causes harsh upshifts and harsh engagements.
Throttle Position (TP) Sensor
The TP sensor detects the position of the throttle plate and sends this information to the processor assembly as varying voltage signal.
The PCM uses the monitored voltage level of the TP sensor for control of LPC, operation and shift scheduling.
If a malfunction occurs in the TP sensor circuit, the processor will recognize that the TP sensor signal is out of specification. The processor will then operate the transaxle in a high capacity mode to prevent transaxle damage.
Powertrain Control Module (PCM)
The PCM controls operation of the transaxle. Many input sensors provide information to the powertrain control module. The PCM then controls the actuators which affect transaxle operation.
Brake Pedal Position Switch
The BPP switch tells the PCM when the brakes are applied. The BPP switch closes when the brakes are applied and opens when they are released. The BPP signal is used for the brake shift interlock actuation.
Turbine Shaft Speed (TSS) Sensor
The TSS sensor is a Hall-effect pickup that sends a signal to the PCM that indicates transaxle turbine shaft input speed. The TSS sensor provides converter turbine speed information for TCC strategy. Also used in determining static LPC pressure settings.
Output Shaft Speed (OSS) Sensor
The sensor is a Hall-effect pickup, located on the transfer shaft drive gear, that sends a signal to the PCM to indicate transaxle output speed. The OSS is used for TCC control and shift scheduling.
Solenoid Body
If the solenoid body identification and strategy does not match the solenoid body information in the powertrain control module (PCM), transaxle damage or driveability concerns can occur.
The solenoid body contains 7 solenoids, 5 shift solenoids (shift solenoid A (SSA) shift solenoid B (SSB) shift solenoid C (SSC) shift solenoid D (SSD) shift solenoid E (SSE)), torque converter clutch (TCC) solenoid and line pressure control (LPC) solenoid. The transmission fluid temperature (TFT) sensor is also located in the solenoid body. The solenoid body is serviced as an assembly.
The solenoid body has a unique strategy data file that must be downloaded to the PCM. There is a 7-digit solenoid body identification and a 13-digit solenoid body strategy for each solenoid body. Anytime a new solenoid body is installed or a new transaxle is installed, the scan tool must be used to get the solenoid body strategy data file and download it into the PCM.
If the PCM is replaced, the solenoid body identification and solenoid body strategy must be downloaded into the PCM.
Line Pressure Control Solenoid
The LPC solenoid is a variable force solenoid (VFS) that varies hydraulic pressure by actuating a hydraulic valve.
The PCM applies variable current to the LPC solenoid which varies pressure in the VBS LINE hydraulic circuit to the main pressure regulator valve. See HYDRAULIC CIRCUITS .
The LPC solenoid uses inversely proportional operation. As the current from the PCM decreases, the pressure from the solenoid increases. As the current from the PCM increases, the pressure from the solenoid decreases. The LPC solenoid is supplied hydraulic pressure from the SOL FD circuit.
With zero current, the LPC solenoid fully opens the hydraulic valve which applies the maximum amount of hydraulic pressure to the Main Pressure Regulator Valve through the VBS LINE hydraulic circuit and applies maximum line pressure in the LINE hydraulic circuit. With maximum current to the solenoid, the hydraulic valve fully closes the outlet port for minimum pressure to the VBS LINE hydraulic circuit to lower the line pressure in the LINE hydraulic circuit.
Scheme 529
Shift Solenoid A (SSA), Shift Solenoid B (SSB), Shift Solenoid C (SSC), Shift Solenoid D (SSD)
Shift solenoids A-D are variable force type solenoids that vary hydraulic pressure by actuating a hydraulic valve.
The PCM applies variable current to the shift solenoids which varies pressure in the hydraulic circuit to the regulator and latch valves of the clutch that it controls. See HYDRAULIC CIRCUITS .
SSA and SSC use proportional operation. As the current from the PCM decreases, the pressure from the solenoid decreases. As the current from the PCM increases, the pressure from the solenoid increases. SSA and SSC are supplied hydraulic pressure from the SOL FD circuit.
With zero current, SSA and SSC fully close the hydraulic valves which applies zero amount of hydraulic pressure to the clutch regulator and latch valves of the clutch that it controls and releases the clutch. With maximum current to the solenoids, the hydraulic valves are fully open for maximum pressure to the clutch regulator and latch valves to apply the clutch.
Scheme 530
SSB and SSD use inversely proportional operation. As the current from the PCM decreases, the pressure from the solenoid increases. As the current from the PCM increases, the pressure from the solenoid decreases. SSB and SSD are supplied hydraulic pressure from the SOL FD circuit.
With zero current, SSB and SSD fully open the hydraulic valves which applies maximum hydraulic pressure to the clutch regulator and latch valves to apply the clutch that it controls. With maximum current to the solenoids, the hydraulic valve is fully closed to apply zero amount of hydraulic pressure to the clutch regulator and latch valves of the clutch that it controls and releases the clutch.
Scheme 531
Shift Solenoid E (SSE)
SSE in an ON/OFF solenoid. When SSE is in the ON position, SSD controls the clutch regulator and latch valves to apply the low/reverse clutch. When SSE is in the OFF position, SSD controls the clutch regulator and latch valves to apply the overdrive (4, 5, 6) clutch. See HYDRAULIC CIRCUITS .
SSE is supplied hydraulic pressure from the SOL FD circuit. When SSE is OFF, the solenoid supply is blocked and the outlet port (ON/OFF SIG circuit) is connected to the exhaust port. When SSE is ON, the exhaust port is blocked and the solenoid supply is connected to the outlet port (ON/OFF SIG circuit), supplying pressure to the clutch control bypass valve.
Scheme 532
Planetary Gearsets
Operation of this transaxle involves the use of the following planetary gearsets
- Front
- Center
- Rear
Apply Clutches
This transaxle uses the following clutches to operate the 3 planetary gearsets
- Forward (1, 2, 3, 4) clutch
- Low/reverse clutch
- Low one way clutch (OWC)
- Direct (3, 5, R) clutch
- Intermediate (2, 6) clutch
- Overdrive (O/D) (4, 5, 6) clutch
For information about planetary gearsets or the apply clutches, see MECHANICAL COMPONENTS AND FUNCTIONS .
Hydraulic System
The hydraulic system of this transaxle consists of the following components
- Transmission fluid pump with filter
- Transmission fluid filler tube with transmission fluid level indicator
- Main control assembly (valve body and solenoid body)
For component information, see HYDRAULIC SYSTEM .