seanjenn Posted March 17, 2012 Share Posted March 17, 2012 Searched but haven't quite found a similar problem. 86 GL wagon One piece headlights, not the 4 individual lights. ALL other lights inside and outside the car work fine. Headlights do not come on, high or low beams, but will come on if you pull back on the hi-lo beam/turn signal stalk. I checked voltage at the three wires for each headlight bulb, here's what I found. Key "on" and HL switch "on" Lo beams Left side wires rd/blu=12V rd/blk=0V rd/wht=12V Right side wires red=0V rd/blk=12V rd/wht=12V Hi beams Left side wires rd/blu=12V rd/blk=0V rd/wht=12V right side wires red=12V rd/blk=12V rd/wht=12V The ground behind the coil and overflow tank looks good, fusible links on overflow tank are intact. Is there another headlight ground on the passenger side, for that headlight or do they both use the one by the coil/overflow? Link to comment Share on other sites More sharing options...
TomRhere Posted March 17, 2012 Share Posted March 17, 2012 Headlight circuits are grounded thru the switch, so I would look at the wiring to the switch. Had simular problem in the '85 BRAT. No headlights at all, but could "Flash" the hi-beams. Found bad connection leading to switch. Link to comment Share on other sites More sharing options...
ivans imports Posted March 17, 2012 Share Posted March 17, 2012 Check headlight realys their is on for left and one for right work both high and low just to left of stering coullum they all clip together to a plastic bracket. If the terminals on the realy have changed coulor it may be burnt. Or try subing in a different headlight switch. Link to comment Share on other sites More sharing options...
Cougar Posted March 17, 2012 Share Posted March 17, 2012 (edited) Like Gloyale stated below, when the lights are turned on there should be 12 volts on the center pin lead of the bulb. The other two pins connect to ground, one at a time, through the switch whenever the HIGH or LOW side is selected. So the voltage should be near zero volts when that side of the bulb should be turned on. Having voltage there means the connection to ground is open somewhere. You do have to be careful if you measure the voltage that way, with the bulbs inserted into the plugs, since the side that isn't turned on will show a voltage also since the ground to it is turned off in the switch. The relays are ok since you have voltage getting to the bulbs and can flash the lights. Edited March 18, 2012 by Cougar Link to comment Share on other sites More sharing options...
Gloyale Posted March 17, 2012 Share Posted March 17, 2012 Your testing is flawed. I am assuming you tested the last time with the plugs connected to the bulb? So 12v coming in on the center pin was feeding back out through the other pins. You are reading backfeed voltage passing through the bulb. Start over. Key on, headlight switch on. Disconnect the plugs from the bulbs. #1 Test for 12v on the center pins of connectors (RH=red,LH=Red/blue). Good? ok, move to #2. Not good? Bad relays or bad fusible link (green one) #2 Now clip the ground lead of the testlight to the positive battery terminal, and probe the outer pins of the headlight plugs. (Red/black for LOW beams, Red/white for HI) If the test light doesn't light....it means the bulbs are not getting the grounds from the switch. Switch gets its ground from 3 different ground eyelets (one on each inner frame rail, and one behind the overflow bottle) If this all tests good...then the problem is with the bulbs. If not, then the problem is with the switch or the circuit back to it. My bet is on the green fusible link.:cool: Link to comment Share on other sites More sharing options...
seanjenn Posted March 18, 2012 Author Share Posted March 18, 2012 Thanks for the ideas, I'll re-do that test tomorrow. Link to comment Share on other sites More sharing options...
Loyale 2.7 Turbo Posted March 18, 2012 Share Posted March 18, 2012 About the Relays, I Kindly suggest you to see This Writeup: http://www.ultimatesubaru.org/forum/showthread.php?t=90403 Kind Regards. Link to comment Share on other sites More sharing options...
Cougar Posted March 18, 2012 Share Posted March 18, 2012 (edited) After reading Gloyale's post I discovered that I wasn't thinking correctly in my first post so I have corrected it. Thanks Gloyale. Edited March 18, 2012 by Cougar Link to comment Share on other sites More sharing options...
themoneypit Posted March 18, 2012 Share Posted March 18, 2012 when you push the switch forward to hi-beam, do they stay on? im betting you have burnt out low beams and its as simple as changing both bulbs. Link to comment Share on other sites More sharing options...
seanjenn Posted March 19, 2012 Author Share Posted March 19, 2012 Did some more(correct) testing per Gloyale. The question I have is with the color of the wires, here's what I've got: LEFT SIDE outer=red/wht middle=red/blk outer=red/blue RIGHT SIDE outer=red middle=red/blk outer=red/wht This is on an 86 GL wagon. When I re-tested the wires I still went with probing the middle wires even though they are a different color than what Gloyale mentioned. Here's what I found with bulbs removed from their plugs and with the key "on". middle wire, right side=.07V middle wire, left side=.08V I also did the test of clipping the test light to the positive side of the battery then probing the outer terminals, no light ever came on. Green fusible link is intact. I've found the GND behind the overflow and another one on the right inner frame rail, just aft of the core support, both are in great shape. Can't find one on the left side. Is it up under the car or should it be in a similar location as the right side? Link to comment Share on other sites More sharing options...
Cougar Posted March 19, 2012 Share Posted March 19, 2012 (edited) Since your voltage test of the middle wires showed no voltage we now need to find out why that is so. Power to the relay contacts is provided by a red fusible link according to my manual but it is for an '88 model so it may be different. Make sure all the fusible links are ok if you haven't done that already. Also make sure the wire connections on the bottom side of the link box are ok as some folks have found problems there. Make sure the fuses in the dash panel are ok using the test light on both sides of the fuses. Power from the relays passes through fuses 7 and 8 in the dash panel and then to the lights. Make sure power is getting to those fuses when the lights are on. If that is ok then there is a break in the wires between the fuse panel and the lights. The fact that the test probe didn't light up when you tested the other wires means there is a problem with the connection to ground also. That may mean there is a connector problem causing this trouble though you did say the passing mode worked ok. Edited March 19, 2012 by Cougar Link to comment Share on other sites More sharing options...
seanjenn Posted March 22, 2012 Author Share Posted March 22, 2012 Looks like I'm in for a new headlight switch. I can get the head lights to come on if I turn them "on" then wiggle the switch around a bit. Link to comment Share on other sites More sharing options...
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