Overhaul - FN4A-El: Description
The FN4A-EL is a 4-speed electronically controlled automatic transaxle that incorporates 4 multi-disc hydraulic clutches, one-way clutches (sprag type) and a friction lined brake band that prevents rotation of sun gear drum. See Fig 1 .
On/off and duty cycle solenoids control shift changes, line pressure and torque converter lock-up. Solenoids are attached to valve body. Solenoids are operated by Powertrain Control Module (PCM).
PCM receives information from various input devices and uses this information to control solenoids for transaxle shifting, line pressure, shift feel and torque converter clutch lock-up.