Sucky backup light issue

[Mark K 2]

I have only one 35 watt backup light on my truck (by choice) and, tonight, I noticed it wasn't working. I troubleshot it as far as I could. It's either a bad connector where I tapped into the Ford factory wiring or a bad backup light switch. It'll have to wait until daylight and a warmer day.



That backup light switch looks like a pisser to get to. It's way up under the dash near the steering column. At least the price has come down on them. They used to cost $75. Now, they're $35 on ebay.

 

[Yardsale]

The factory reverse lights have been disconnected? \

 

[Mark K 2]

The factory reverse lights have been disconnected? \

They're now amber turn signals. I was going to bring my ST to England in 2003 when I accepted a job there. I changed my mind, but left the European conversion in place. A Euro conversion includes turn signals on the front fenders, amber rear turn signals, a red rear fog light, and converted headlights to H4 bulbs.



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[Yardsale]

Okay.



You don't note specifically - did you test the bulb (gotta ask)?



I'm trying to figure how much of the factory circuit is in place and used for the light you now have. I assume that you tapped in to the factory wiring at the switch and ran a new wire, or under the dash.



For the connector, maybe shake it (inexact, I know), or maybe just replace it (if it's easy access). You can check for voltage before and after the connector, and at the light. If these are negative, then explore the switch or dark underbelly of dash.



Is the switch under the dash the only one controlling the light - I believe there is a position switch in the transmission that may have an interaction as well.

 

[Mark K 2]

I have no voltage at the bulb. The bulb tests good using an ohmmeter. I have to crawl under the truck to check the connector where I tapped into the factory harness. In salty-roads Wisconsin, I'm betting that's where the problem is. I pray it's not the neutral start/backup switch. That thing is next to impossible to get to.

 

[user 62851]

I'd like to know your fix to this also. Have link for the backup light switch on ebay? Is the neutral start/back up switch expensive and hard to replace without a shop? I haven't had reverse lights in almost 2 years. Bulbs work fine. Connector on each side of truck have no power. I have been tempted to just let FORD fix this issue but haven't gone around to do so yet.

 

[Yardsale]

In salty-roads Wisconsin, I'm betting that's where the problem is.

Hopefully.



I live in southern California, where we have almost no corrosion problems, and I solder all my wire joints.

 

[Mark K 2]

The hell! All this time, I thought the neutral start/backup light switch was on the steering column. Well, sh*t! It's on the transmission! It's the black thingy with the linkage attached to it.

 

[Yardsale]

Yes, it is.



Check those voltages.

 

[Mark K 2]

Well... The wiring from the switch to the light is fine. I tested it with a 12 volt source and the light lit up. Power to the switch is fine. It's the switch. I ordered a new Borg-Warner switch on eBay for $24. The local auto parts store wanted $60 and Ford wanted $76.

 

[EddieS'04]

Mark,



I thought that was where it was. I was afraid to stick my neck out, to say so. Glad found it..:supercool:

 

[Yardsale]

Considering that you don't have to ferret under the dash, all-in-all, not a bad repair, and $24.00 isn't bad.

 

[Mark K 2]

I replaced the switch. It didn't fix the problem. I suspected a different issue. I crawled underneath to inspect the wiring that I installed 15 years ago. Oh.... Time and living in the rust belt has not been good for my truck. Found a bad splice connector and that fixed the backup light problem.



So, I pulled the truck in the garage and closed the door. I always hit the brakes to see if the brake lights reflect off the door. No brake lights, but the center one worked. Ratshit. Took off the tail lights and found another bad butt splice. Man... I can hardly wait for that new Ranger to be on the market.

 

[Yardsale]

This is why I solder and shrink wrap all my wiring.