Pinpoint Test 8

Flow Chart No. 8 - Symptom - Backup lamps inoperative.

Step 1
Check bulbs and bulb sockets.
1. Remove backup lamp bulbs, then check bulbs for broken filaments. Check bulb sockets for corrosion and damage.




2. Are bulbs and sockets serviceable?

Step 2
Check battery feed to bulb socket.




1. Set parking brake, then turn ignition switch to ON and shift transmission into reverse.
2. Check for voltage at socket battery feed terminal (B/P).




3. Is voltage more than 10 V?

Step 3
Check ground circuit.




1. Connect for continuity between bulb socket and clean chassis ground.




2. Is there continuity?

Step 4
Backup lamp switch feed.
1. Set parking brake, then turn ignition switch to ON.




2. Disconnect TR sensor (A/T) or backup lamp switch (M/T) connector.
3. Check for battery voltage at switch feed wire (PU/O).




4. Is battery voltage present?

Step 5
Check switch continuity.
1. Shift transmission into reverse.
2. Check for continuity across switch battery feed (B/P) terminal feeding backup lamps.




3. Is there continuity?