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Rico1234 04-09-2012 11:36 AM

Headlight Issue
Hi Guys,

I am having a strange issue with my headlights where one light is low beam and one is high beam. When i turn on high beams it goes opposite the high goes low on one side and the low goes high.

I replaced both bulbs to make sure it was not different bulbs causing the problem.

The person i bought the car from had an accident and the the left headlight assembly was replaced and they told me the problem started after that.

I thought to buy a multi meter and test the wires to see if the same are getting power with low or high beams.

Any ideas what would cause this?



sailor 04-09-2012 02:26 PM

Gee, if it was in an accident, and the headlight was replaced, ya THINK someone MAY have "messed up" the wiring when they repaired it....??

yeah, check with a meter, but B4 that just look to see if the wires are hooked up the same on each side... And yeah, the bulbs weren't a bad guess as some bulbs are wired backwards from similar ones that might fit...

Rico1234 04-10-2012 08:21 AM

yeah I didn't see any wires or plug that looked as if it was "repaired" but logically it is the only thing that makes sense.

I can't see where the wires go because they seem to go inside the light housing itself so I may have to actually unbolt the headlight assembly and see what the rest of the wire looks like and where it goes (if there is plug or hard wired into the harness).

A couple times i thought to just take it in to the dealer to let them figure it out but with the prices they charge and it being something that i can do myself with a little bit of time and effort i thought to try to fix it myself.

I am also starting to think that with little replies to this and so much knowledge on here that it really is starting to look like something that is rarely encountered if ever and probably some body shop screw up.

Tymes 04-10-2012 04:17 PM

I'd try to find out from the previous owner what the actual damage was, that might help you to know where to look. If there was damage beyond just the headlight, they may have replaced a large section of wiring which would mean you need to look for a splice deeper into the body then just at the headlight itself.

The wire harness will plug into the headlight assmbly ( or it should) so the wiring inside will either be fine or factory defect. You could remove both assemblies and plug them in opposite sides of the car to see if they react the same, that would tell you for sure if the assembly was bad or the car wiring.

Oh and welcome to the forum, finally I see another Ottawa member.

Rico1234 04-10-2012 08:08 PM

Hi Tymes thanks for the help it is great how the forum can bring together people from all over and even close by :).
I originally got the car as good a to b car but have really grown attached to it now and enjoy driving it.
If the wiring seems different for low and high beams i may even just splice the wires and wire it up the correct way if it turns out to be the problem but i will try as you say to compare both sides.

Tymes 04-10-2012 08:27 PM

The main reason I suggest that is if right now when you have low beam on, and your driver side is actually in high beam mode, and you move it to the passenger side and it is still in high beam mode, then you know it is a factory defect. If it is in low beam mode like it should be when it's moved over then you know its the wiring itself.

Trust me, nothing sucks worse then looking for a wiring issue when you have no chance of ever finding it. My car is a bit different, but if its any indication, the headlights are quite easy to remove, mine take less then 5 mins to pull out.

Rico1234 04-11-2012 10:31 PM

Yeah electrical/wiring problems are usually something most people don't look forward to but at least this problem is only to do with the headlights and not the ignition system.

sailor 04-11-2012 11:13 PM

Hey, FWIW - I was just working on an old Mustang that had the driver's mirror replaced years ago. Ever since, the up & down was backwards on that one but the owner was just happy it worked. When I was in the door to replace the window regulator, I re-wired the mirror plug, since the wires in the repl. mirror were backwards to the plug in the door....

new part, wired backwards, factory or not - it was messed up B4 installation...


Rico1234 04-11-2012 11:21 PM

Hey thanks Sailor that is good to know and just goes to show it is possible to be wired incorrectly.

If i do find the wires going to the plug appear wrong I shouldn't have any issues if i splice the wires and connect them proper finishing with black electrical tape should I? I don't think the headlights draw that much current thought the wires that it would heat up much?

Tymes 04-12-2012 04:06 AM

Ahh, tell you what, if you find the harness was spliced, let me know and I'll solder them and heat sink them. that's an area that gets very wet, and you'll end up with corroded wires if it not done up good.

I'm out of town this weekend, today till Sunday, but anytime next week in the evenings.

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