[hand_in_ga]

I have a 2004 Jeep Grand Cherokee Overland that is experiencing some electrical issues. One issue is the headlights. I recently noticed that one of the headlights was out. So I replaced the dim headlight and then the bright headlight went out. So I replaced that light and thought all was well. Well now the dim headlight is noticeably dimmer than the other side and when I turn on the bright lights it goes out all together.

Then the other day, my wife was driving and the radio went off along with the digital displays and several other functions. She got it home and after turning it off she turned it back on and everything came back on. Really strange. I don't know if these 2 things are related or not, but I'm wonder if there may be a ground somewhere causing these problems.

Oh, one other thing I just thought of. We replace the battery last summer but about a month ago when I went to leave the house, it wouldn't start. I jumped it off and haven't had that happen again, but it does seem sluggish when starting it sometimes. Like it's not going to start at first, but then it does.

Any ideas or suggestions? I have a multimeter and wiring diagrams but wanted to consult the "resident experts" before diving in to troubleshooting. Thanks in advance!

 

[paintdrying]

A ground is a great place to start. If Jeep is a chrsyler then their is a bunch of Mickey mouse gizmos in there that are a waste of space. I would check every connection on that Jeep. Sounds like a flat spot on the starter motor. Maybe an ignition switch. These modern cars just have so much junk on them it is really dishearten to trouble shoot them. Sart with a factory service manual and a test light.

 

[hand_in_ga]

Thanks for your response. My wife had mentioned it to the guys at the shop when she got some brake work done recently and they said they could do a diagnostic for $90. My question is, what exactly would they do for their "diagnostic"? I had another vehicle with electrical issues a few years ago and when she took it in to have it checked out (I'm in the Navy and was out to sea at the time), they couldn't find anything. So I feel like this would be just a waste of money. I'm capable of doing the work, just have limited time after work each day. Anyway, I'll get started checking for grounds. Thanks again!

 

[rusty baker]

It does sound like a "ground" problem.

 

[polarzak]

Just for fun, check your alternator output. Idling and under load.

 

[paintdrying]

The 90$ check could be the best thing going. Is your check engine light on? They may just hook your car to the computer and if nothing comes up they are done. You are out 90 bucks. If they are going to do electrical trouble shooting for an hour, then maybe. Every time I have taken my car in I have always been very disappointed by the service. Their is a guy in town here, he charges 150 bucks no matter what. He will find the problem because he is an incredible mechanic. What I have found in my time as a mechanic is do not even think about the problem, just jump into it and check a whole list of items right off the bat. Your problem could be as simple as a loose battery cable. Or as complicated as something that just can not be fixed by anyone.

 

[Billy_Bob]

Check the voltage with it running. Should be around 13 or 14 volts. If a lot higher than that, it could cause problems and I would check your voltage regulator/alternator.

Also I did have two headlights go out at the exact same time! I also purchased them at the same time, so that make sense. But I assumed it must be an electrical problem! I went to track down the problem with the wiring and there was no problem!

Anyway possible your headlights are going out all at the same time - unusual, but possible.

 

[hand_in_ga]

Thanks for all the recommendations. The thing with the headlights though is that one went out, I replaced it, then another went out and I replaced it, and so on. Now one of the ones I just replaced is out again. plus, it still doesn't explain why they are really dim all of a sudden. Checked alternator output - 14.2V at 2000 rpm. It just seems like I'm dropping voltage somewhere. That's the only thing that makes sense to me as to why the headlights are so dim. Or maybe the relay that drives the headlamps is faulty? Maybe it's the DRL that are on instead of the actual low beams. Sorry, just trying to think it through as I type. As for the brights, I probably just blew that bulb... again. Which makes me think that something is just not right electrically. Still searching... suggestions are still welcome, I'll update you with any new findings.

Thanks.

 

[hand_in_ga]

Update...

I think I've found the smoking gun. I took the headlamp assembly out and started to remove the lowbeam bulb. When I did, the light came on. When I let go, it went out again. So I thought maybe a loose wire in the connector. So I took the bulb out and put the multimeter leads in the sockets and wiggled the wire around, no change in voltage. So now I'm scratching my head. So I put the bulb back in and it came on again. Then I realized as long as I was holding the bulb in, it would stay on. So it appears that the bulb assembly is not seating all the way in the connector. I guess the connector has worn so that it doesn't hold the bulb assembly in place as it should. So I'm going to look into replacing the connectors (other side is doing the same thing) and see if that fixes the problem. I'll post my results when I do. Thanks again to all!

 

[Billy_Bob]

That is weird that a new light would go out. To my knowledge, a "too high" of voltage would cause them to fail right away. I don't think a "too low" of a voltage would cause them to fail?

If no one knows here, might want to call one of the headlight manufacturer's and ask what can cause them to fail so soon.

Then are these factory specification bulbs/headlights? (Not HID or some modified headlight system?)

I did find this basic stuff on headlights with a google search...
http://www.ehow.com/list_7427867_causes-car-headlights-burn-out_.html

Anyway if a too high a voltage could cause this and you can't find any other reason for these burning out, then I would connect a multimeter inside the vehicle and monitor the voltage as I drove.

Also it is a good idea to connect the "burned out" bulbs to another 12 volt source or directly to a battery to be sure they are in fact burned out. This can be done with alligator test leads like these (Radio Shack or electronics store)...

 

[cjm94]

It's not that uncommon for the connectors to go bad on headlights. As far as the bulb burning out fast make sure you don't touch the glass of the bulb. The oils from your skin can create hot spots on the bulbs causing them to fail prematurely.

 

[oh'mike]

from HOGHUNTER2

It's your bulb sockets. The contacts are like a spring load pushing agains the bulb contacts. They weaken over time and 9 out of 10 times I have success by using a scribe to pull the contact tab in the socket back out so the push thighter against the bulb. If the sockets are burnt or browned in color then you best just get some new socket pigtails and splice them in using some quality but connectors. Poor contact in the socket will cause high resistance thus resulting in dim light or blown light. Put a bit of dylectric grease in the sockets to keep moisture out.

 

[oh'mike]

Note to new member---scroll down on this page and you will find a reply box---type answer there---click on 'quick reply'

 

[paintdrying]

Advanced auto has those socket plugs, they are sort of hard to find. I was going to have around ten dollars between the wires, connectors and shrink tape. I thought to myself "paint, that is 2 trips to chinese buffet, just soldier the wires directly to the headlight"