Last month (March) I bought a 1985 Ford F-150.

300 CID Straight Six
Two Wheel Drive
Single Cab

It still is missing it's plates because I can't pass inspection. The reason I can't pass inspection is because my backup lights won't come on. I don't know why, and I've tried to find the problem. I don't know what to do.

Anyone have any ideas?

 

First off,check the fuses that control your lights.If they're okay,then check your wiring to make sure it isn't cut.If your truck is equipped with one,try cleaning out your neutral safety switch and then adjusting it.I'm not sure what transmissions had them and which ones didn't,but on my C6,the neutral safety switch was on the linkage of the transmission on the driver's sides.Maybe someone else can jump in with more info.

 

also check your bulbs in the back.what trans do you have? if standard also check your reverse switch on the trans.

 

I just put all brand new bulbs.

1985 Ford F-150
Automatic Transmission
300 CID Straight Six
Two Wheel Drive

I went and followed the lines all the way from the back to the front. Maybe I missed something.

Also, my license plate lights won't work. I'm sure it's related, but I don't know where the problem is.

 

Have you checked fuses?Are your front lights working just fine?Is the transmission an AOD?

 

jumper the switch on the left side of the C6

more info here

https://www.ford-trucks.com/forums/7...ey-switch.html

 

Agreed.

However,I had a problem with my C6,the colors on the NSS weren't matching up to the factory wiring diagrams.Mine had only two wires,which were brown and black,the color of the reverse light wires.There was supposed to be 4.However,my NSS still functions as the truck won't start unless in P or N.I don't think I ever figured it out.

Here's the NSS from my C6.

 

First, get a voltmeter and check for power at the back-up light socket with the key on and tranny in reverse. If you have power at the black/pink wire, you have a ground problem at the socket.

If you don't have power at the black/pink, move on to the tranny. What automatic transmission do you actually have? I noticed some people jumped to C6, but I haven't heard you say anything. If you have an AOD, which is what I suspect given your year and engine, you'll find a four wire switch on the left side of the tranny. This switch is your neutral safety/backuplight switch. Remove the harness to that switch and with the key on, use a voltmeter and check for 12V+ at the purple/orange wire. If you have power, jump the purple/orange and black/pink wires and check for power at the black/pink at the back-up light socket. If you have power with wires jumped, replace the switch in the tranny. If you don't check the plug where the tailight harness plugs into the truck harness for corrosion. If you still don't have power, replace the black/pink wire between the tranny switch and the backup light sockets.

If you have no power at the purple/orange wire, check under the frame rails leading towards the front and also under the brake booster for connectors that might be corroded. If your directionals are working, it isn't a fuse problem, so if all else fails, run a new wire from keyed 12V+ to the purple/orange wire at the tranny switch.

 

On my truck, the not starting unless it is in P. or N is mechanical in the column... not electrical.
Jim

 

I have a C6 transmission.

Tomorrow, I will do what you guys told me and see if it works. XD

 

I was wondering what you came up with. I have the same problems. All other lights work...directional, running, everything.

 

As do I. I just started my lighting work today, so this thread is quite timely!

 

I did a little further investigating of my issue, and this is what I came up with.

First, I have a C6 tranny. When I move the gear selector from P to R, I don't get any backup lights. If I move the selector from N/D to R, sometimes the backup lights will come on.

So, I guess it's the NSS? Can this switch be cleaned? Adjusted?

 

hello I have the same problem does the connection look like this but near the transmission.