Dim Headlights

i took my grill and radiator out a few months ago while replacing my lifters. When I put it back together and reconnected my headlights my headlights are really dim. I had an issue with my alternator not charging so I assumed this was why they were dim. I found the bad wire at my alternator and have that fixed and now my alternator is charging just fine. But...I still have really dim headlights. Can anyone think of why I might have dim headlights? Each light simply has a three prong plug and a ground wire and everything seems to be connected. I know it's a long shot but I thought I'd ask.

 

Make sure your connections are clean and your ground circuit is adequate. Load test your battery to see if it is within parameters.

 

yep each headlight has a body ground wire off the plug

 

I agree with Howard. I have run extra grounds from frame to body panels, engine and alternator to just be sure. I tie them together and use star washers. Grounds typically are the go to issue. I had this very issue with my front turn signals. Bad ground was the culprit.

 

While you're there checking grounds, consider running the lights through a relay if you haven't already, they'll get cleaner power and probably brighten up a bit.

 

I'm reading some stuff on line about adding relays to the wiring. Considering giving this a try. Just can't get my head around what I might have done to the wiring when removing and replacing the grille and headlight buckets.

Took the light out again. Both appear to be grounded well. Or at least grounded the same as they were before I took the grill out.

 

Clean the plugs at the headlights and run a dedicated ground wire to the battery.

 

The sheet metal makes a poor ground for the headlights. Try adding a second wire under each headlight ground and running it all the way back to the battery. Bypass the grille and fender ground path entirely.

Adding relays will make your lights brighter... but you will get the full benefit if you improve the grounds too.

 

You didn't somehow hook em up in series did ya??

 

I may have fixed my problem by accident. I pulled the lights and pulled the plugs just checking for connection issues. Hard to really check the briteness during the day but last night on the way home from my neighbors the lights are working much better. I think maybe simply plugging them in and unplugging them may have cleaned the terminals some. Same thing for the ground wires.

I will run a straight ground to the battery later. Does each light need its own ground wire or can I run the ground from one light and tie it into the ground from the other light and then a single wire on to the battery?

 

Single 14 ga wire will be fine - or you could run 2 16 ga. Any copper wire will be a big improvement over the route through the sheet metal. The larger the wire the better, but no need to go wild.

Contact cleaner is a good thing to have on hand. Amazon.com: Hosa Cable D5S6 Deoxit Contact Cleaner Spray: Musical Instruments Put a little dielectric grease on the contacts and grounds if corrosion is a problem. http://www.amazon.com/Permatex-2205...=1464008966&sr=8-2&keywords=dielectric+grease

 

Thanks Tim. I haven't seen any corrosion on anything. It's all nice and clean. Those ground connections on the grill still have paint behind them, which I could see being a problem. Seems like maybe I should scratch the paint away behind the ground connections. Either way, I will get rid of those grounds and run straight to the battery. Thanks fellas.

 

Glad I could help! If you use a toothed washer under the ground screw and next to the fender, it should go right through the paint and into the steel. However, it won't hurt to scrape away the paint.

 

As an electrician all I can say is yes get the paint off and down to metal.. Also the tighter the connection the better..

 

A good ground makes a lot of difference. I learned about dielectric grease from working on my Harley. Started using it on my other vehicles as well.

 

OK...I have a schematic showing how to wire in a relay but I'm not sure I know how to tell which wire is the high beam wire and which is the low beam wire. I'm fairly certain the plug on the headlight itself is a three prong plug. One of those prongs is for the ground wire.

Also...I think I recall that the harness of wires coming from the fire wall to the driver's side head light has 4 wires in it. Two wires go to one prong and two wires go to the other prong. Or maybe that's just two wires going to that first headlight and two similar wire leaving the DS headlight and going to the PS headlight.

Still...how do I tell which wire is the high beam light?

 

Do you have a multimeter or a test light? Turn on high beams with one bulb unplugged and see which connection is hot.

Or read the circuit diagram, and identify the high beam by color.

Anyway ... you don't need to know which wire is high beam. Pretty sure there's just a pair of wires on the fender, and they continue from one headlight to the other. Have the '84 TSM? There's a high beam wire, a low beam wire, and ground at the bucket. You need two relays, one for high and one for low. They are wired in the same. So it does not matter. Identify the two wires going to the headlights, and install a relay in each.

 

There's an '82 diagram here - Jeep® 1982 TSM online

An '84 is probably the same as an '82. You have five wires going to the grille, two for the headlights and three for the parks/indcators/clearance lights. That diagram shows a gray and gray with white trace wires for the headlights.

 

There's a few of us that have installed a bimetal grounding bus bar, I found mine for $5 clams at the local Hab for Humanity out of an AC fuse panel. I ran a 6 gauge wire from the negative battery post of my primary battery to it, them all of the grounds I can find to the bus bar. I dielectric greased the works and if you're at NAPA the cost difference between the small tube and large tube is negligble, there's always room for more grease!