Front Axle Shift Motor Test: Command-Trac
- Raise and support vehicle. Disconnect vacuum harness from front axle shift motor. Connect vacuum pump to shift motor front port. See Fig 1
. Apply 15 in. Hg to shift motor. Rotate right front wheel to disengage axle (2WD operation).
Courtesy of CHRYSLER MOTORS.
- Shift motor should hold vacuum at least 30 seconds. If not, replace motor. If motor holds vacuum, disconnect vacuum pump from shift motor front port. Connect pump to shift motor rear port and cap indicator light switch port. See Fig 1
. Apply 15 in. Hg to motor.
- Shift motor should hold vacuum for at least 30 seconds. If motor does not hold vacuum, replace motor. If motor holds vacuum, remove cap from shift motor indicator light switch port and check for vacuum.
- If vacuum is present, shift motor function is normal. If vacuum is not present, apply 15 in. Hg to shift motor rear port. Rotate right front wheel and ensure outer and intermediate axle shafts are engaged (4WD operation).
- Axles must be completely engaged to open indicator light switch port. Check for vacuum at indicator light switch port. If vacuum is present, shift motor function is normal. If vacuum is not present, replace shift motor.