GM S10/S15/Sonoma Pick-Ups 1982-1993 Repair Manual
Back-Up Light Switch
REMOVAL & INSTALLATION
Disconnect the negative battery cable.
Locate the switch on the left or right rear of the transmission housing (depending on the application), the back-up light switch is threaded into the transmission case. The speed sensor is held in with a separate bracket. Disengage the electrical connector from the back-up light switch.
Remove the back-up light switch from the transmission.
To install, reverse the removal procedures.
With the engine NOT running (for safety), place the gear shift lever in the reverse position and check that the back-up lights work.