GM 14009262 Switch

With the ignition switch in the Run or Start position, voltage is applied through the turn signal/backup light fuse to the backup light switch. When the gear selector is shifted to the Reverse position, the backup switch closes, providing voltage to the backup lights. If both backup lights don't work, check the turn/backup fuse by operating the turn signal lights and verify the backup switch adjustment by moving the gear selector lever to Reverse. If both lights still do not work, secure the vehicle to prevent rolling backwards. With the ignition switch in the Run position, place the gear selector lever in Reverse and attach a test light to pin B (dark blue wire) of the backup switch and ground. On some models, the backup light switch is located on the transaxle housing instead of the shifter assembly, but the checking procedure remains the same. If the test light does not glow, check the dark blue wire for an open. If the test light does glow, attach it to pin A (light green wire) of the backup switch and ground. If the test light glows, replace the backup switch; if it does not glow, ensure that the bulbs are functioning properly.