I have a 1985 Cougar 3.8l v6 with a C5 tranny. I recently replaced my transmission and my reverse lights worked fine for about 2 weeks then they stopped working. So I replaced the neutral safety switch, and still nothing. All fuses are fine. Turn signals still work. I am stumped. I hope someone can help.
Have someone watch the backup lights as you move gear selector through P-R-N-D. See if they ever come on. Maybe the linkage is a little out of adjustment.
I have tried that. They don't come on at all. The bulbs are new LED's that I just put in, tested them in other sockets and they work just fine. Could switching to LED's have something to do with it?
Don't know why LEDs don't work. Can you put the 1156 bulbs back in?
Check for voltage at the bulb socket with your multimeter.
I had an LED 1156 bulb burn out when I tried it...very possible they blew. As softtouch said, try the regular bulbs.
I have tried all that. No power at the socket. And the regular bulbs don't work either. Both sets of bulbs are brand new out of the pack. Thats why I'm stumped. I have tried everything I can think of and consulted with a couple mechanics I know and they were stumped as well. Is there a relay somewhere that could have gone bad? If so where is it?
The reverse switch is seperate from the neutral safety switch. It is a single two pr0nged sensor with only two wires going to it. Make sure it has power going to one side of the harness, otherwise its not the reverse switch, it will be an electrical gremlin in the car somewhere probably.
This is a C5 NSS/Backup switch:
If you still have the old switch, figure out which pair of wires is for the Backup lights. Use your OHM meter to check for continuity. The NSS will have continuity in two positions, park and neutral. The Backup will have continuity in just the one position.
[COLOR="#FF0000"][COLOR="#FF0000"][/COLOR] UN-PLUG THE RED/LIGHT BLUE WIRE FROM THE STARTER RELAY TO AVOID ACCIDENTALY STARTING THE STARTER MOTOR WHILE MAKING THE UNDER THE CAR CHECKS[/COLOR].
[COLOR="#FF0000"]FOR GOOD MEASURE ALSO PULL THE HIGH VOLTAGE WIRE TO THE DISTRIBUTOR OUT OF THE COIL. ACCIDENTALY JUMPERING VOLTAGE TO ONE OF THE NSS WIRES COULD START THE CAR WHILE IT IS IN REVERSE[/COLOR][COLOR="#FF0000"][/COLOR]
Take a good light under the car. Unplug the switch connector. Examine the plug ends to see if any of the wires have unlatched and pushed back into the plug.
With the trans in reverse check for continuity through the switch.
Replug the connector.
With the ignition in Run, Back probe for voltage on the purple/orange wire and the black/pink wire in the cable harness connector plug.