Models With PWM Solenoid

Overdrive Range - Fourth Gear (Converter Clutch Applied) (Models With PWM Solenoid):

OVERDRIVE RANGE - FOURTH GEAR
(CONVERTER CLUTCH APPLIED)
(MODELS CONTAINING PWM)

"A" SHIFT SOLENOID - ON
SECOND CLUTCH - APPLIED
1/2 SUPPORT ROLLER CLUTCH - OVERRUNNING
"B" SHIFT SOLENOID - OFF
THIRD CLUTCH - APPLIED/NOT EFFECTIVE
FORWARD BAND - APPLIED
*PWM SOLENOID - ON
THIRD ROLLER CLUTCH - OVERRUNNING
TCC SOLENOID - ON
FOURTH CLUTCH - APPLIED

To obtain fourth gear, the PCM receives input signals from the VS Sensor and TP Sensor in order to energize or "turn on current" supply to "A" shift solenoid (315). When energized, line pressure is directed into the "A" shift solenoid passage to the 3-4 shift valve (362). "A" shift solenoid pressure shifts the valve against spring pressure allowing 3rd fluid to enter the 4th and 4th clutch fluid passages. 4th fluid seats No. 10 checkball (372) and forces it through a feed orifice to stroke the 3-4 accumulator piston (428) while applying the 4th clutch. 3-4 accumulator fluid on the spring side of the piston is forced through the 3-4 accumulator pin (426) into the 3-4accumulator passage and exhausts at the 3-4 accumulator valve (350).

"A" Shift Solenoid (315): Energizes to prevent fluid from exhausting out of the line passage and "A" shift solenoid passage.

1-2 Shift Valve (318): Is held against "A" shift solenoid by spring pressure and "B" shift solenoid off fluid pressure at the end of the valve.

3-4 Shift Valve (362): When shifted against spring force, it allows 3rd fluid to enter the 4th and 4th clutch fluid passages. 4th fluid seats No. 10 checkball (372) and is forced through a feed orifice before stroking the3-44 accumulator piston (428) and applying the fourth clutch.

No. 10 Checkball (372): Located in the valve body (300), it forces 4th fluid through a feed orifice into the 4th clutch passage to stroke the 3-4 accumulator piston (428).

3-4 Accumulator Piston (428): Cushions the apply of the 4th clutch by using 4th clutch fluid to stroke the piston against spring force and 3-4 accumulator fluid.

3 - 4 Accumulator Valve (350): Controls the rate of exhaust of 3-4 accumulator fluid during 4th clutch apply.

* SOME MODELS