Before I give up and wire a switch to do the job gudnuf fo gubment, I thought I would give y'all a run at it. I have been a long time lurker but created an account to post. Thanks for the years of tips. Y'all do good work.

Current Status:
98 Ranger XLT has 12v to left back up lamp but it won't come on. No juice to the right side..BUT the wiring appears to be good or at least has continuity from the rear light harness connection to the wires.

Recent Related History:
I need a brake tag/inspection sticker and no back up lights has not been a problem for the last 10 or 12 years, but this year is different no matter when I go. Why has it been 10 years? Because I hate forking with electrical on a vehicle. Really dislike it and this endeavor has only strengthened my disdain. Anyway... I started up front and was not getting power to the main harness but had good fuses (this was a new issue from my last run at this problem a few years ago). I replaced the switch on the transmission and got 12v power to the main harness but no joy on the lamps producing light. Multimeter read 12v at the bulb's socket connections and the bulb is a complete circuit. I switched the left turn signal bulb and backup bulb. The bulb that failed in the back up socket worked in the blinker and the working blinker bulb failed in the back up socket so the bulb is confirmed good. I finally break down and yank off the left side which is a task because as the name says, it's a busted 98. Anyway a wrench, a screwgun and a long reach around yields a taillight hanging. The backup lamp socket and connector are more busted the taillight attachment. The bulb is good but there is no power reading on the multi. Remove the socket and break the connector, as is tradition. No power at the connector and intermittent continuity at the socket connections as icing. Pulled apart the rear harness connector and get a good power reading from the hot leading back to the main harness. I proceeded to rest for continuity on the disconnected side and all wires test good (right and left) for hot to hot and ground to ground. Plugged it all back in and still no power in the right side. I even cut the connector off and stripped to bare wire. Still nada.

That's my story. Do y'all have any suggestions before I wire up the switch from the fuse box and ground the lights to the frame? Thanks in advance!

 

I am no Electrical Guru as RonD is... butt, if you have a constant switched 12 volts at the sockets, check the grounding at the light(s) both in the socket and at the ground point, could be the socket itself just being old !

If the grounding at the light is good... just guessing, trace the wire backward and see if there is a problem with the wire itself; i.e. wear, chafing, shorting.

Just talking out loud !

 

Welcome to the forum

I assume you are using regular bulbs, NOT LEDs because they have a + and - polarity and only work one-way in a socket, you just need to reverse them in the socket to get them to work

From description I would say the socket was bad

The 3 sockets in each tail light share the same ground wire, so if one socket has an intermittent or no ground condition then just cut and splice that wire to another sockets WORKING ground wire

The 3 sockets are
Park/brake, dual filament bulb
Turn
Reverse

Each has 1 ground wire

Most tail light issues, 99%, are from past trailer wiring hook ups, your 1998 has had 23 years of trailer wiring exposure to the elements, and its location means ALOT of elements have been thrown its way being behind a rear tire, lol

Don't over think it
If all the lights work except for the reverse light on one side then(assuming good bulb) that light bulb is missing either 12v or ground
If its missing 12v then run a new wire to the working Reverse light
If its missing ground then splice it to a wire with working ground

 

Thanks for your RonD and Scrambler82.

I grabbed all of the stuff to rig a switch and replace the right side socket. After replacing the socket and connector, I noticed an odd bit of behavior. Maybe this will trigger something for y'all. When either side has a bulb in, the other side gets no power. Works out the same with a jumper wire in place of the bulb. Works the same with the old socket removed on the left side and a jumper. Works the same with the new socket removed and jumper.

In the meantime, I will try running a ground wire for each side.

 

Tried grounding each socket straight to the frame. No joy.

 

I replied earlier but the post isn't showing.

Thanks for the replies and ideas scrambler and rond.

Long story short, new socket and connector on the busted side. Both sides get power but not at the same time. If a circuit is complete by bulb or by jumper on one side, the other side gets no power.

 

Key is ON
Light switch OFF
Trans is in Reverse(tire blocked)
Engine is OFF

Both reverse bulb sockets should have 12volts on one wire, the Black/pink stripe wire, it is the 12volt wire for Reverse lights
Solid black wire is the ground

Black/pink wire runs from the transmissions "reverse switch" to the rear of the truck
Ford used 2 wiring methods
First just has the ONE black/pink wire from transmission spliced to TWO black.pink wires under the bed, each of those wires ran to one of the reverse bulbs

Other method was the one black pink wire from transmission ran to Drivers side tail light socket, then 2nd black/pink wire ran from that socket over to passenger side tail light


When in doubt, turn on Park lights, if the Park light is on then it has a GOOD ground wire, use that wire

Electricity always finds the easiest PATH to a good ground
And that can be THRU another light bulb, so that light bulb glows, not full brightness like its "on", but it will light up dimly, problem is NOT that dim bulb, problem is the light you are trying to fix has a poor ground
Bare metal is a ground, painted or rusted metal is not

 

Not true. Electricity will always take ALL paths, not just the one with the least resistance. Parallel paths will always create parallel current flows.

However, in many cases with two or more paths, one path usually has very little resistance. The majority of current will flow on this path. But there will be some current on the high-resistance paths as well.

 

True, but not sure how that will help with this issue

 

Another day, have you tried anything new ?

Results ?

Pictures of the housing socket !

Also, if you haven't already done so, remove the housings and take a look at the wiring on the backside of the housing.
Sometime a quick look will give you a different story.

If the sockets are bad, you may need to go through either Rock Auto or LMC to get replacements.
I have found the O'Riley's and Auto Part PLus's Sockets are less than good quality... BUT they will still work if the need is high.

Luck,

 

Thanks y'all. I won't be able to break it all down again until the weekend. I tried grounding it straight to the wirebrushed bare metal on the frame to the ground side of the sockets and still no joy. I did not splice into the tail light grounds yet. I will try that next time I have time. If that fails, I am just going to wire a direct line from the fuse box to a switch 3 post switch to pass the stupid inspection. I am now 4 months out of spec.

I did get a connector and socket from O'Reily because the need is pressing. The socket was confirmed bad and I broke/destroyed the connector while taking it apart. All the wiring that I unwrapped was still intact and well wrapped. The trailer wire looks good and has no obvious abrasions. The protection plug is still firmly in place and no visible signs of damage/corrosion inside the plug.

 

Don't over think it

If you have 12volts on the Black/pink wire, at rear of truck when trans is in Reverse, and only when in Reverse, then the wire to that point is OK

You just need 2 wires from that wire to each Reverse bulb socket
Don't spend alot of time, well any more time, lol, unwrapping wires to find the issue, you can do that at a later time, or never
Run new wires, pass the inspection

 

busted98,

How did this work out ?