Solenoids 1, 2, 3 and 4
SOLENOIDS 1 AND 2: Solenoids 1 and 2 provide gear selection of first through fourth gears by controlling
the pressure to the three shift valves.
Actuator: Shift Solenoid 1 (SS1)
Transmission function: Gear selection
Symptoms: Improper gear selection depending on failure mode and manual lever position; see the Solenoid ON/OFF Chart on Page 21.
Test codes: 91*, 49**, 59**, 69**
Actuator: Shift Solenoid 2 (SS2)
Transmission function: Gear selection
Symptoms: Improper gear selection depending on failure mode and manual lever position; see the Solenoid ON/OFF Chart on Page 21.
Test codes: 91*, 49**, 69**
SOLENOID 3: Solenoid 3 provides torque converter clutch control by shifting the converter clutch
control valve to lock or unlock the torque converter
Actuator: Converter Clutch Control (CCC)
Transmission function: Engage converter clutch
Symptoms: Failed on - engine stalls in drive at idle low speeds with brake applied and manual 2 Failed off - converter clutch never engages
Test codes: 94*, 62**
* Output circuit check, generated only by electrical condition.
** May also be generated by some other non-electronic transmission hardware condition.
SOLENOID 4: Solenoid 4 provides coast clutch control by shifting the coast clutch shift valve.
Solenoid 4 can be activated by pressing the overdrive cancel switch or by selecting the 1, or 2 range with the transmission selector lever. In manual 1 and 2, the coast clutch is controlled by solenoid 4 and also hydraulically as a fail safe to ensure engine braking. In Reverse, the coast clutch is controlled hydraulically only and the S4 solenoid is not on.
Actuator: Coast Clutch Solenoid (CCS)
Transmission function: Engage coast clutch to provide engine braking in 3rd gear when overdrive cancel is on.
Symptoms: Failed on - 3rd gear engine braking with O/D range selected. Failed off - no 3rd gear engine braking in overdrive cancel
Test codes: 93*
The VFS is an electro-hydraulic actuator combining a solenoid and a regulating valve. It produces Electronic Pressure Control (EPC) which regulates transmission line pressure. This is done by producing resisting forces to the main regulator valve and the line modulator valve. These two modified pressures control the clutch application pressures.
Actuator: Electronic Pressure Control (EPC)
Transmission function: Regulate TV pressure
Symptoms: Failed on - Gasoline engine, minimum. TV pressure (minimum. capacity) limit engine torque (partial fuel shut-off, heavy mis-fire), flashing overdrive cancel light.
Failed on - Diesel engine, cut power on ECA pin 35 (EPC power) to attain maximum TV
SOLENOID OPERATION: Solenoids 1 through 4 operate in the following manner:
When the solenoid is off, the fluid pressure feed is blocked by a check ball. The check ball is held in place by the solenoid armature spring.
When the solenoid is turned on by the processor assembly, the armature is pulled up. This releases the check ball and applies fluid pressure to the transmission control system.
* Output circuit check, generated only by electrical condition.