This is listed under 99 Mountaneer
Transfer Case
Motor, Electric Shift
The externally mounted transfer case shift motor (7G360), located at the rear of the transfer case (7A195), turns the shift cam assembly. As the shift cam assembly turns, it positions the reduction shift fork (7289) for desired transfer case operation. An integral position sensor in the shift motor provides motor position information to the generic electronic module (GEM).
Switch, Rotary 4x4 Mode
The rotary 4x4 mode switch, mounted on the instrument panel, allows the operator to select the 4WD Auto, 4WD High, and 4WD Low transfer case operating modes. The indicator light, above the rotary switch dial, will illuminate when the 4WD High or 4WD Low position has engaged.
Switch, Brake Pedal Position (BPP)
The brake pedal position (BPP) switch is located on the brake pedal. The switch signals the GEM when the operator activates the brake pedal.
Switch, Clutch Pedal Position (CPP)
The clutch pedal position (CPP) switch is located on the clutch pedal bracket. On vehicles equipped with a manual transmission (7003) and an electronic shift transfer case, the clutch pedal must be fully depressed and vehicle stopped in order to make a range shift from HIGH to LOW, or from LOW to HIGH.
Sensor, Digital Transmission Range (DTR)
The DTR sensor is located on the outside of the transmission near the transmission shift cable attachment. The DTR sensor completes the start circuit in PARK and NEUTRAL, the back-up lamp circuit in REVERSE and the neutral sense circuit (4WD) in NEUTRAL. The DTR sensor also sends a digital output signal to the powertrain control module (PCM) (12A650) indicating the manual lever position (P, R, N, D, 2, 1).
Sensor, Throttle Position (TP)
The TP sensor is located on the throttle body. The sensor provides throttle position information to the PCM. The PCM converts the throttle position signal to a pulse width modulated (PWM) signal, and sends it to the GEM to control and adjust the transfer case clutch duty cycle.
Sensor, Front and Rear Output Shaft Speed (OSS)
The externally mounted OSS sensors are located at the rear of the transfer case. The sensors provide the GEM with front and rear driveshaft speeds to control and adjust the transfer case clutch duty cycle.
Sensor, Vehicle Speed Sensor (VSS)
The Anti-Lock Brake System (ABS) provides the GEM with vehicle speed information to control and adjust the transfer case clutch duty cycle.
Generic Electrical Module (GEM)
The GEM controls the operation of the transfer case in response to inputs from the electric shift motor, 4x4 mode switch, CPP switch, BPP switch, DTR sensor, throttle position output from the PCM, front and rear OSS sensors, and the VSS.
Electronic Shift Control System Components
Item | Part Number | Description |
---|
1 | 7G360 | Transfer case shift motor |
2 | 7F293 | Front output shaft speed sensor |
3 | 7F293 | Rear output shaft speed sensor |
4 | — | Shift range selector switch |
5 | 14B205 | Generic electronic module (GEM) (electric shift only) |
6 | — | Digital transmission range (DTR) sensor |
Mechanical Operation
The Borg-Warner 44-05 transfer case is available in the Explorer (A4WD) vehicle. The transfer case transfers power from the transmission to the rear axle, and also to the front axle when electronically activated.
In the Auto mode, torque from the transmission is transferred to the input shaft (7017) which, in turn, drives the rear output shaft (7061) that drives the rear axle assembly (4006). The electromechanical ball ramp clutch assembly drives the drive sprocket (7177) after the GEM activates the clutch coil. The drive sprocket turns the drive chain (7A029) that rotates the front output shaft and the front driveshaft (4602). In the 4x4 High mode, the operation is the same as in the Auto mode, except that the GEM consistently activates the electromechanical ball ramp clutch assembly.
The high-low shift occurs when the reduction shift fork moves the high-low collar (7100) to lock the planetary gear set to the output shaft. Then, torque, transmitted through the sun gear, from the input shaft, turns the front planetary gear set assembly (7A398). The front planetary gear set assembly, which is now engaged, provides transfer case speed reduction.
Transfer Case Functions
There are three transfer case modes, Auto, 4WD Low, and 4WD High. Neutral is only available as a dealer installed option.
Control-Trac Function
The Control-Trac transfer case uses an electromechanical clutch assembly to control torque to the front wheels. In the Auto mode, while at rest and under cruising conditions, the GEM activates the transfer case clutch at a minimum level. This allows for the slight difference between the front and rear driveshafts which occurs normally when negotiating a corner on dry pavement. Under any of the following conditions, the GEM will increase the torque sent through the clutch to the front wheels in order to prevent or control slip.
- Slip is detected (by monitoring the front and rear OSS sensors in the transfer case)
- Throttle position (by using the throttle position signal from the EEC)
Range Function
NOTE: At zero throttle, the duty cycle remains low. At very light to heavy acceleration, the duty cycle jumps to the maximum.
In the 4WD Low Range, with throttle input, the transfer case electromechanical clutch locks the front and rear driveshafts for maximum 4WD traction. The transfer case shift motor rotates the shift cam to move the reduction shift fork to the 4WD low range position. This low range shift, accomplished through a planetary gear set, changes the torque to the driveshaft from 1:1 to 2.48:1 ratio.
In the 4WD High Range, with throttle input, the GEM signals the transfer case electromechanical clutch to lock the front and the rear driveshafts for maximum 4WD traction. Never use the 4WD High range when driving on dry or merely wet pavement. Use the 4WD High range only for driving off-road or in severe winter weather.