1st Generation Toyota Tacoma (2003) Left Rear Tail Light Wiring Diagram

This is literally just a free information posting that I'm trying to put up in good will to fellow 1st gen. Tacoma community folks. I was wiring a truck cap and was trying to scour the internet for what should have been a quick look as to which wires to splice for the 3rd brake light on the cap. You'd think that would be easy to google, huh? Couldn't find it on google or youtube so I'm posting it here for future people.

I'll post a pic in a minute from my phone, but its easier to type on the desktop computer.

Please feel free to correct me if I'm wrong here, but my cap's 3rd brake light is working so I at least have those two wires right (ground and brake).

 

That's the first gen wiring harness to the driver side taillight.

Going upper left position (as seen on pic) clockwise around it. Black/white is ground. Double solid green as flashers/hazard. Double green w/ black as left turn. Double green w/ white is brakelight. Double Black/red is backup. Single green is running light.

So I spliced the he Black/White wire and the Green/white to the 3rd brake line from the truck cap. It worked.

 

You actually need 4 different diagrams for the entire tail light assembly: Taillight and Illumination, Turn Signal and Hazard Warning Light, Stop Light, and Backup Light.
You also tapped into your trailer harness jumper (which is a good thing) instead of the stock wiring. That's why you have double wires.

I've attached all 4 wiring diagrams to this post. These will work for all 01-04 trucks, 95-00 is slightly different with the location of a ground.

 

Yup... those were the same FSM diagrams I referenced that lead me to decide what to tap.

Btw... could you define "trailer harness jumper" because the mess of mostly green between my fingers IS the OE wires that clips directly into my tail light. Thats what I originally unplugged in the first place to add the trailer harness. You can see the trailer harness plugged into the factory plug (dangling down with the yellow, white, brown wires).

 

Oh you’re right about the trailer harness. That’s my mistake. The double wires must be going to the other taillight. That’s one of the differences between 01-04 and 95-00.

 

Soldered and heat shrink ??

If not the first application of Liquid brine in a few days it will no longer be working.

That stuff gets in every place

 

Yes sir! Soldered and heat shrinked. Was my first time doing that.

 

Not to thread jack, but I can't get my passenger side running light to work. The brake light works fine, and I've replaced the bulb. Driver side everything is all good.

If I'm reading the diagrams correct, green wire goes into pin #2 on drivers side, leaves from pin #6 to travel to passenger pin #2. I saw another thread, someone had said the spade connector had corroded. Are these plugs replaceable or rebuildable?

Can I just tap a wire off the green feeding driver #2, and route that over to #2 on passenger? Is there a need to travel through the connector?

 

Interesting questions. Sorry, I'm definitely not a mechanic. My goal was to provide an easy resource above to show someone what wires to tap for wiring their truck cap since I scoured the internet fruitlessly.

Not sure?

Try it and see?

Yeah, sorry.

 

Time to break out your Meter and find the problem.

Sockets corrode

it is possible to get the bulb in wrong

You can repin any of the Toyota Plugs if you can get the correct parts.

If your doing Electrical work the best thing is to have a copy of the Electrical wiring diagrams for your vehicle .

I won`t do electrical work without it .

 

Check your ground, seems like that is a common drama for 12v DC, especially in northern (rust promoting areas)

 

I encountered a thief and they stole my driver's side tail lamp assembly. They cut the wires as my photo. My model is 2001.

May I confirm the each wire to the connector (R6) is as follows?

1 one G-B
2 two G
3 two W-B
4 two G-W
5 two R-B
6 one G

Thank you for your help and best regards,

 

Thank you for posting this! I wanted to report that I bought an 03 trd with 400k+ miles. I was installing a trailer harness and new front turn signal lamps. My lights kept doing weird things such as the left turn signal would only work when the lights weren't on. I checked all my grounds. The battery terminal ground wire was undersized so I upgraded that. All of the tail light harness pigtail connectors were very oxidized and I couldn't get them clean. I ended up hard wiring the left turn signal before it would work properly. Then, my right running tail light would blow the fuse every time. I ended up hard wiring the grounds together for the right tail lamp to bypass the oxidized pigtail and viola, the fuse quit breaking. To diagnose this, I ended up putting a 30 amp fuse in so that the tail light fuse wouldn't blow. Then I immediately wiggled the right tail light pigtail to discover that depending on how I wiggled it,the better the rear light would work. I then hardwired the neutral and put in the 10 amp fuse. Problem solved. I wouldn't recommend leaving an oversized fuse in because the short will continue to heat up the wires until you have a fire. The experts are right 70-90% of the time, it's a grounding problem.

 

No neutral in DC circuits !!

Just positive and negative !

 

Did you ever figure this out? I'm having the exact same issue with my '01 and I can't figure it out.

 

I also had the same issue, and just fixed it thanks to this thread. I had tried changing bulb, looked at fuse box, and then looked at my wiring and redid a ground wire that was rusting off. That didn’t work, so finally took a close enough look and found that the green wire had broken past the connector socket thing. I snipped the same wire before the connector piece, and attached them with a heat shrink around the connector and seems to be working well

 

Is the taillights harness still available from Toyota ?
Ty