Backup Lamp Switch: Description and Operation
DESCRIPTIONThe Transmission Range (TR) Sensor incorporates a series of step down resistors which act as a voltage divider.
The TR sensor houses START circuits, BACKUP lamp circuits and 4x4 LOW-NEUTRAL sense circuits.
PURPOSE
The powertrain control module monitors the voltage which corresponds to the position of the range sensor.
This information is used in determining desired gear and electronic pressure control pressure.
The TR sensor also houses the START circuits for the ignition system to allow the driver to start the vehicle in PARK or NEUTRAL.
The TR sensor allows driver to engage 4x4 low transfer case from the "NEUTRAL" position only.
With transmission in REVERSE, this switch allows current flow to illuminate backup lamps.
When transmission range sensor is in the reverse position the day/night mirror returns to or remains in the day position.