iowabucks

Hey everyone, first post here.

I apologize for this topic, as i'm sure it's been hashed out many times before. But it's late and I have been searching all night for some info.

My son has a 94 Toyota 2WD pickup. It has terribly dim headlights. I told him to try some halogen lights, but they didn't help much. The Sylvania XtraVision lamps at our local Autozone.

I started to read a thread about 4crawler's harness and then got sidetracked. but I noticed it was a pretty old thread. As far as I know they are still unavailable right now.

Does anyone know if they can be found anywhere? Or if not, is there a comparable harness on the market? Cheap is good, right now. A flashlight would light up the road better then his headlights do now.

I could possibly make my own harness if the parts are available locally. Anybody tried that before?

What's the best quick fix for now?

RSR

Here: https://www.yotatech.com/forums/f131.../#post52106589

Discombobulated

Hmmmm, xtravisions shouldn't be bad enough to be compared with a flashlight and jumping on the Internet to ask about it, are you sure you might not have other issues, low voltage, wiring issues? Can you get any night shots of this??

iowabucks

I'm sure it is a voltage issue. I have done a little research today and found it's a fairly common thing.

I haven't had a chance to check the Toyota's wiring voltages yet, but I did see the rather dim bulbs in action this afternoon. Shining the lights on my garage door in the shade from 8 feet, compared to my Grand Am, I could barely see any light projecting onto the garage door at all.

RSR

Your battery is probably failing. Common thing to happen in the heat of the summer. Batteries don't like really hot or really cold...

iowabucks

We just bought the truck the other day and was told the battery is fairly new. I will get it load tested as soon as I can. Thanks.

scope103

If the headlights are dim with the truck running, it's not the battery (the voltage "on the bus" is set by the alternator; it will be about 14.1-ish even with a completely busted battery.)

Get a voltmeter and some scraps of wire; use the wire so that you can measure the voltage right at the headlights. If it's anything less than 11v, that's your problem, and replacing the bulbs won't make any difference. Then all you need to do is trace the wire back to find where you've got a corroded connection.

This is a safety issue; don't horse around with it.

iowabucks

14.2v at the headlights when running, with 14.4v at the battery. Lost maybe .25v with the engine off.

So voltages look good, but headlights still dim. I cleaned one plug with contact cleaner and filed the contact areas, and the prongs of the headlight.

This is a bad picture from my phone, during the day, with a bright background. So I will get some nighttime pictures this weekend.

So if this is all the brighter the stock headlights will get, a harness wont give it any more power. Would the Hella conversion headlights be the best bet for brighter lights?

Oh, and it's hard to tell but it has hit a deer and messed up the corner, but we have the headlight in solid and pointed as well as we can until I can ride with him at night.

scope103

wow.

There's nothing fancy about headlights for this truck; they should be just as bright as any other car. And yours aren't.

If you have 14.2v at the lamps, it probably isn't a truck-wiring issue. The lamps themselves aren't that expensive; have you tried replacing one? Unlike the sealed-beam of yor, they actually have a bulb inside the reflector, with the glass lense glued on. After many years, that glue can fail, letting water inside. (I haven't seen water causing dimming, but what do I know?)

iowabucks

They are new Sylvania Xtravision headlamps.

RSR

That's pretty bad. Try bulbs first.

If not that, try cleaning your grounds. It might help...

donomite49

x2 on the grounds. you can use a meter to check ground resistance.
my xtra vision beams are still bright and work good, for sealed beams, for over ten years.

RSR

I *think* the light grounds default to the stock ground next to the battery. If so, corrosion at the battery terminal or on the wire itself under it's lining/insulation might be the culprit. Definitely clean the battery terminals, and then clean your ground location w/ steel wool. Wouldn't help to sand off a little paint either for a better connection. Another good and cheap option that you should be able to screw on to the stock connector is walmart sells a 6 awg 1 foot battery cable for lawn and garden items, that would definitely be an upgrade from your likely corroded stock ~8awg battery to frame cable.

Also, wanted to mention the Hellas or other light housing upgrade (almost anything is better than sealed IMHO) -- recently documented mine here: https://www.yotatech.com/forums/f116...ersion-272021/

One of my stocks was Wagner and the other Sylvania.

jb451

x3 on the grounds... Bad grounds can wreck havoc on headlights. I had a bad ground and it made one headlight bright and the other dim...

RAD4Runner

Concur.

Where did you probe for voltage at bulb? (Refer to schematic below, but ignore notes.) If you probed with positive (red) test probe at bulb positive (pin3), and negative (black) test probe at battery post, you are not measuring voltage that actually gets to the filament. The best way to measure the actual voltage is directly across the bulb. Pos probe to pin 3, black probe to pin 1 (Red Wire-Grn stripe) for low beam and black probe to pin 2 (Red-Yellow) for high beam. To make it easy, pull the bulb connector slightly out, just enough so you can access the connector blades with the test probes (Observe Safety First).

Too low a voltage means excessive voltage drop probably because of high resistance in wiring / connections and more likely in the convoluted ground path [ask 4crawler ] from bulb negative, to cabin, to dash, to dimmer-switch back to engine compartment to chassis ground near the fuse block, to battery.



To improve ground connection:
Sand away the paint where connectors make contact like others are saying, like this:


Also relocate headlight ground wires (white with black stripe) to contact bat-to-chassis wire like this:


A harness will significantly reduce voltage drop in wiring and add power. See headlight link in my sig.

Yes, one of the best, but that is merely a band-aid; the stock wiring that is still crap. The robust fix would be:

1. Eliminate any wiring defect,
2. Address the excessive voltage drop inherent in the the crap stock circuit (i.e., with the conversion harness like this)
3. Then, get a higher efficiency housing/bulb, like the Hella's that RSR mentions ^^.
   Autopal is about half the price and significantly brighter than stock sealed beam but has poor beam-pattern (search this topic).
   

dropzone

iTrader: (6)

very good points on the grounds...

iowabucks

I slid the plug halfway off and used one prong of the headlight for + and the body or bolthead closeby for the -.

Checking the ground cables contact definitely sounds like it could be the culprit. But I have to wait for my son to get back over here to check it out. Hopefully within a day or two.

I will report back after that.

Discombobulated

K, because the pics are making my OCD run rampant. But really would like to see this fixed with some new pics

RAD4Runner

That will give you deceivingly high enough voltage going to the bulb even if there are tons of voltage drop on ground path.
Repeat...
The best way to measure the actual voltage is directly across the bulb. Pos probe to pin 3, black probe to pin 1 (Red Wire-Grn stripe) for low beam and black probe to pin 2 (Red-Yellow) for high beam. To make it easy, pull the bulb connector slightly out, just enough so you can access the connector blades with the test probes (Observe Safety First).

iowabucks

More work, no better results.

I found the ground strap from the body to the neg cable was down to about a 1/3 of the usual strands of copper where it goes into the top post clamp. I thought, that must be it. Put a new end on it, cleaned the posts, not any better.

By measuring voltage from the 3 blades of the headlight, it now looks like it's losing 1.25v by the time it gets to the headlight. 14.25v at the battery, 13.05v at the headlight, while running. Maybe it does need the headlight harness.

I would have a different picture to post of the headlights but the lighting conditions were different from the other day. Wouldn't be a very accurate comparison. If anything, the change is so slight, it's barely noticeable.