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Where is the high beam switch and relay?


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check fuses first

the switch is at the base of the turn signal (push stalk to/from you for high, low, and flash) - the relays are above the driver's side kickpanel - they are round canisters with a 4-wire connector going into their base

 

good luck

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After looking at my wiring diagram for reference it seems the way I had thought the headlights worked was incorrect. I had previously thought that the center wire to the headlight connector was always ground to both the low and high beam filaments but after looking at my manual it appears the ground wire changes and the filaments are in series with each other when the high beams on. I though they were in parallel.

 

This means your fuses and relays are ok since they power the low beams also. The problem would seem it is due to either the headlight switch, the wire to the headlights for the high beam ground is open or, both the high beam filaments are open. Could it be? Checking the filaments with a ohmmeter will tell the story.

 

EDIT:

For those that read this post please note that after further consultation with one of our other top board members (Skip) I have found out that my above thoughts on the wiring are incorrect due to a misprint in the factory service manual. The power wire to both filaments is in the center of the headlight connector and the ground connections to the other side of each filament is provided through the light switch. Fuses 7 and 8 provide power to the left and right lights respectively.

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After looking at my wiring diagram for reference it seems the way I had thought the headlights worked was incorrect. I had previously thought that the center wire to the headlight connector was always ground to both the low and high beam filaments but after looking at my manual it appears the ground wire changes and the filaments are in series with each other when the high beams on. I though they were in parallel.

 

This means your fuses and relays are ok since they power the low beams also. The problem would seem it is due to either the headlight switch, the wire to the headlights for the high beam ground is open or, both the high beam filaments are open. Could it be? Checking the filaments with a ohmmeter will tell the story.

 

Thanks for the information,

 

well, im quite a newbie in mechanical and electrical stuff, so it may take a while to figure out what you just said, but hey! i will learn...

 

what do you mean by both filaments being open? and by high beam ground being open? this would mean that curent is not passing?

 

Thanks again

 

Submage

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OK - I thought about your problem, and I have a *theory*

first question, is your alternator working properly - most auto parts stores will test for free

 

if you alternator's voltage regulator fails, and puts more voltage through your system than it is supposed to get, you will start buning-out stuff

 

typically, one of the first things to go are your headlights - your headlights have a single bulb, but each bulb has two filiments in it; one for high-beam, and one for high and low beam operation - the high-beam filiment is under higher thermal stress (though it is not used as much), so I would expect it to be the first one to go - if both high-beam filiments are burnt out, then you will get the problem you are describing

 

*NOTE* if you replace/examine your headlights DO NOT touch the glass part!! it will cause the lamp to fail soon after it is installed - the lamp could even explode - if you do accidentally touch it, clean the bulb with rubbing alcohol thourghly, and allow to air-dry

 

another possibility is that someone put the wrong type headlight bulbs in - they should be 9004 - if they are 9007 or anything else, they will NOT work properly

 

and of course, there is the last possibility that the switch itself could be faulty, but as it is the hardest & most expensive thing to replace, I would put it last on my to-do list

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What I mean is this. The filaments in a bulb are the small pieces of wire that glow so brightly and make the light. There is a high beam filament in each light and I suspect that both lights have a burned out (another way of saying the filments have opened up or become disconnected from the outside contacts) high beam filament. You are correct in saying current stops flowing in an open circuit. It is the same as turning a switch to 'off' (it opens the circuit). In a closed circuit the current can flow.

 

Don't worry about being a newbie. You will pick up things real quick. Especially if you like it.

 

 

Thanks for the information,

 

well, im quite a newbie in mechanical and electrical stuff, so it may take a while to figure out what you just said, but hey! i will learn...

 

what do you mean by both filaments being open? and by high beam ground being open? this would mean that curent is not passing?

 

Thanks again

 

Submage

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Thanks guys,

 

so first thing is to look if the high beam filament is burned, im guessing that it kind of looks like a fuse in the bulb, if yes, the alternator is overpowering the system ( or is just an old light). Do i have to remove somthing?

 

Ok now this, i just bought myself a multimeter and have no clue on what ''chanel'' to put it on or how to use it to do the testing, im thinking that i will need this to test the wiering from swith to relay, and relay to light (event thow im still not shure where they are and what they look like). Is this test only to see continuety of circuit or to see how much ''current'' is passing? That brings me to an other question...

 

It seems there are swaps for 90 amp alternators. In the light of what you are saying, this would be a bad idea no? Some ppl in this forum consider putting a GM P7157 alternator for better performance of electrical systems...

 

many thanks again

 

submage

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OK - I would recommend you download "How to Keep Your Subaru Alive" and read the section on multimeters - I like the book overall, and there is funny stuff, but there are also some mistakes on the level of maitnence certain components require, so don't take it TOO seriously (timing belt every 20k, fram filters, and natural oil ... yeah right) - realize it was written over 17 years ago.... stuff along those lines has changed, but the info on accessing/adjusting stuff and how it works is great

 

anyway - you will need to use the resistance (continuity) setting - the symbol is the omega (the measurement unit for resistance is ohms) - one lead (usually red) is plugged into the place that has the omega symbol, and the other is plugged into "common" disconnect the wire from one of the headlights - turn the car on, with headlights on low beam and check the continuity between the body of the car, and each of the terminals (there are three) on the wire going to the headlight - you will get a reading of zero resistance at one of the wires - if not, you either have a problem with the meter, or you don't have a good ground to the chassis - once you do get a reading of zero (or near to it) resistance, switch the headlight switch to high beam - chect the resistances again in the same fashion as previously, you should get a reading of zero (or near zero) resistance at one of the wires - it should be a different one than you had previously noticed zero resistance on - if that is the case, and you do get the the zero resistance reading, then you just need to replace the headlights (no big deal), if not; then you have a more complicated problem

 

to check to be sure your alternator is not over-volting the electrical system, use the "Volt" range and appropriate probe on the multimeter - connect the positive lead from the meter to battery positive, and the negative to battery negative - with the car idling, you should get ~12.5-14.5 volts - rev the engine up to about 4,000 - 5,000 RPMs and check the voltage - it should not be above 15 volts MAX - if goes any higher than that, you have a bad alternator (not hard to replace, and well under $100 for a reman)

 

Unless you have or intend to add a LOT of power-guzzeling accessories to your car, a GM or other alternator upgrade is NOT necessary (I use stock with NO problem) - it won't hurt if done properly, but it is not something for the novice mechanic to do .... yet

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With all due respect to 85Sub4WD, I don't recommend using the advice on checking the resistance of the headlight wires with power on. One of the 3 leads has power going to it when the lights are on and one of the first lessons on learning to use a multimeter is never measure resistance with a meter when power is applied to the circuit. If you have an analog meter you may damage it, at best, blow a fuse in it.

 

Instead of measuring resistance of the wiring you can measure the resistance of the bulb filaments to see if the bulb is good. Remove the connector from the light and measure across each of the filament leads. Since they are tied together it won't matter what leads you choose to measure across. The resistance will be real low on both leads. You most likely are going to find out one section is open.

 

To learn how to use your meter you should be able to do a search of the net to find out some info. I would purchase a book that covers the subject also. Knowing how to use one these real important in my book. You will wonder how you got along without it before.

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Yes - Cougar is right about the multimeter concern, I wan't thinking an along meter because I never use them anymore - digitals cost a little bit more, but they are worth every cent of it

 

most any new Digital Multimeter (DMM) will have extensive isolation circuitry, that makes it a null issue whether there is/isn't voltage between the two connections (they allow you to be rather sloppy) when you check impedence - in fact, one of my friends has an automotive multimeter that tells you under some troubleshooting proceedures to use the impedence check across a 12V source ....

 

I was actually thinking about that manual for it when I wrote the post - my DMM (Craftsman) is over 10 years old, has seen 12V across the impedence circuit many times, and it has required one battery change, and a new set of probes since I got it new - it still works perfectly - yes, at age 10 my parents gave me a digital multimeter (birthday present) - I am a nerd - guess what my major is

 

my biggest caution is to NOT use the current function unless you know EXACTALLY what you are doing - that can cause smoke if used improperly

 

actually a easier/more foolproof way to test the circuit itself (after you check the lamps) would be to use a test light (light bulb in pointer thingy), turn the car on, and connect one lead to battery + and then check the terminals to see if it lights up - it should light up on both high and low beam settings on different terminals for each setting - test lights are probably $4 or less, but for more complex troubleshooting, you will still need the DMM - they are a critical tool to troubleshooting most any electrical problem, other than a blown bulb

 

good luck

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Well, looked at the filaments in the bulbs and they seem to be ok, and i even tried a new bulb to be shure. Nada... Nothing... Darkness suronding the car... Hehe...

 

i suspect that the switch is the problem, so... guess what i did. Found myself an other multiple function switch for the subby. Em going to try to install it myself tomorow, and im hoping that i was guessing good. Hope it aint to hard to get that in to there... hehe...

 

I was wondering, im hearing a grounding motor noise from the passenger side floor, i just got the car so i dont know what sounds are normal..? Could my manifold gaskets be tired, and if yes, is this hard to fix?

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Ok, well, how should i say this. The swich aint the problem... Instaled a new one today and it did not help my high light beam. I re read this thread and seemed to overlook the testing of the wires, so this is probably what im going to do tomorow with my multimeter. Will have to figur out a cople of things on the multimeeter, but seems this is my last chance at sucess in this venture... Oh and i f***** my steering wheel... lol... I tried to take it off with a jake and a chain... Oups, kids, do not try this at home... REALY!!!

 

Wich me luck

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Ok, let's see if you have power getting to the headlights. Set your meter to read DC volts. Then put the common lead of the meter to a good ground and the other probe lead to the red wire of the right side headlight. You should have power there. If not then you should check the red fusible link. It may be blown or have a bad connection. You may be able to save a step by checking to see if the fusible link is ok first. Chances are it is bad.

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Submage:

 

In case you are still working on this problem I think I may know the cure to the problem you are having. I wanted to make sure I understand the problem correctly so I don't lead you the wrong way.

 

After reading your posts again the way I understand the problem to be is that the low beams work ok but the high beams do not. If this is so, and you have tried a new light in the socket (it was previously mentioned to make sure that the proper model bulb is installed, model 9004) to make sure that the high beam filaments are ok, then the problem would have to be with the high beam ground wire connection which is a red/white wire. There is a dual sided 8 pin connector (F64) under the dash near the drivers door that the wire passes through. It may be that the problem is there. To prove it you could tie the R/W wire at the light socket to a good ground and see if the lights turn on. If that works then try tieing the R/W wire to ground at the light switch. If the lights don't work then check the R/W wire at that connector if you can find it. There are a lot of connectors in that area. If you can't find the connector you could run another wire between the light connector and the switch to fix the problem.

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