Charles Patterson Posted August 29, 2006 Share Posted August 29, 2006 I have an early 240z series 1. If I put the fuses in the fuse box, the headlights burn regardless of the position of the headlight switch. On the early wiring diagram there is a passing relay shown, but I can't locate this in the dash or under the hood. I may not have one, I don't know. If I seperate the 12 ga wire betweeen the column switches the lights go out. Any ideas? Thanks, Charles Quote Link to comment Share on other sites More sharing options...
240ZR Posted August 29, 2006 Share Posted August 29, 2006 meh i rewired mine to give me a switch to turn them off indapendantly of the parking lights........ so with my limited knowladge, of what i did, do the parking lights stay on? what about with high beams? Quote Link to comment Share on other sites More sharing options...
srgunz Posted August 29, 2006 Share Posted August 29, 2006 This headlight diagram may help you. Are you saying you bought it this way or you have owned it and it just suddenly happened? Quote Link to comment Share on other sites More sharing options...
ZDrifter Posted August 29, 2006 Share Posted August 29, 2006 I dont mean to steal this thread or anything but I am having lighting problems aswell. My passenger side headlight wont work, drivers side works both low beam and high beam, and my turn signals arent working. I put a new relay in for the turn signals and still nothing, I also checked the fuses and they are good. I have been messing around with ground wires but cant get them working. I only started having these problems after my RB swap. so if anyone knows exactly where the grounds are or have any other advice that would help out a lot! Thanks Quote Link to comment Share on other sites More sharing options...
fastzcars Posted August 30, 2006 Share Posted August 30, 2006 I'll try to help. here's the link to a large copy of the whole wiring harness to a 240zhttp://album.hybridz.org/showphoto.php?photo=2126&size=big&cat=&si=wiring What color wires did you disconnect to get the lights to go off? It could be a bad combo switch , they are know to go bad. Now the head lights are being fed a constant positive 12 volts through the large RED and RED/YELOW wires from the fuse block. The red/blue and the red/white wires are actually the ground path for the lights. Ya I know it's a round a bout way of doing it, but hey that's the way the factory did it. So the means that there is a ground short of either the red/blue or the red/white wires. You could disconnect the combo light switch, to see if that is the problem. If you still have the problem after disconnecting the switch I would venture to say that you may have to untape the engine compartment wiring harness and see if you can find the grounding problem. Without a voltmeter/ohm meter you are forced to do a visual check of the all the head light circuits wiring. When I redid my wiring ,I found several wires from the old harness burnt to a crisp. Not to scare you , but the wiring in the z are over 30 years old, lot's of things may have been changed from previous owners and or just age of the wire insulation. Get a volt/ohm meter and we can help you further. Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted August 30, 2006 Share Posted August 30, 2006 I've heard our early Z car headlights refered to as "positive ground", is this true? if so, what does this mean? Quote Link to comment Share on other sites More sharing options...
fastzcars Posted August 30, 2006 Share Posted August 30, 2006 J. Soileau RB26zcar I've heard our early Z car headlights refered to as "positive ground", is this true? if so, what does this mean? Well it's true, to a point. The car is not a positive ground system just the head light circuit . I think they did it that way to reduce the current draw through the combo switch, but it didn't work as well as they hoped. Quote Link to comment Share on other sites More sharing options...
fastzcars Posted August 30, 2006 Share Posted August 30, 2006 ZDrifter My passenger side headlight wont work, drivers side works both low beam and high beam, and my turn signals arent working. I put a new relay in for the turn signals and still nothing, I also checked the fuses and they are good. I have been messing around with ground wires but cant get them working. I only started having these problems after my RB swap. so if anyone knows exactly where the grounds are or have any other advice that would help out a lot! Thanks I would check your hazard light switch. The turn signal's are going through this switch. as for the ground's there are some on the from frame rails, right next to the heading buckets. and the main ground line is on the passenger side frame rail, right below the battery box. That location is notoriuos for have problems beacuse of the battery acid running down the inner fender and no to the framerail. I hope that helps:D Quote Link to comment Share on other sites More sharing options...
ZDrifter Posted August 30, 2006 Share Posted August 30, 2006 Come to think of it, i pulled out my center console during the swap and didnt plug anything back in so if i get what your saying, to complete the power circuit for the hazard/turn signals the switch has to be plugged in? I would be so happy if its as simple as that, I will have to try it in the morning then let you guys know what happens, thanks for the info! Quote Link to comment Share on other sites More sharing options...
bjhines Posted August 30, 2006 Share Posted August 30, 2006 A lot of cars send constant power through the fuse box to the headlights and horns, etc.... then the "ground" is routed back to the switch, button, etc.... The reason for this is to protect the switch from short circuits... the switch ends up last in line from the battery... if anything shorts out anywhere along the path... it will never draw high current through the switch... because the switch is the last thing in line... If your HEADLIGHTS STAY ON then you have a short along the path from the lights to the switch... somewhere... This path runs from the front clip.... back along the passenger frame rail, through the firewall grommet under the battery tray, up to the top of the dashboard, across to the steering column, through the switch and to ground.... If you were BLOWING FUSES... then you would have a short between the fuse panel and the healights... following almost the same path in the opposite direction... If ONLY ONE HEADLIGHT WORKS then there is an open circuit most likely in the front clip where there are 3 splices for LOW, HIGH, and GROUND connections... the splices are relatively close together on the passenger side frnot clip... right where the right hand lighting wires split off.... Early cars had lighting grounds on the front clip(subject to a lot of corrosion).... Later cars ran this back to the passenger side framerail near the starter(subject to poor splices)... Both designs have issues.... Quote Link to comment Share on other sites More sharing options...
bjhines Posted August 30, 2006 Share Posted August 30, 2006 Looking at the diagram posted... it appears that this one has both the MAIN switch and the HIGH/LOW switch one right after the other in series(still last thing before ground though)... BUT... I swear I have run into a later 73 240/260Z harness that had them widely separated in the circuit... Quote Link to comment Share on other sites More sharing options...
Charles Patterson Posted September 5, 2006 Author Share Posted September 5, 2006 I got my headlights working. I think the problem was the combo switch. I think I took a later series switch and installed it on a series 1 car. The car I am working on now. I switched it back, they didn't work, then they did, then they didn't. Anyway they work right now. so we'll see. I have most of the electrical sorted out, but I have another problem the wipers... I have owned 240's for almost 20 yrs. This car I am working on now was my daily driver at least 11 yrs ago. It sat for almost 10 of those. Family, kids, work whatever. So I am going throught it and trying to get it back on the road (we have a new derilict car ordinance here; like it's any of the goverments business). So anyway there is corrosion, the usual melted circuit in the fuse box (running lights). So I have soldered all the terminals in the fuse box like they recommend on the Blue ridgeZclub site (early style w/ the long leads) It seems the running light circuit uses a haevier gauge wire in my later z fuse boxes. Any way the wipers. I found the diagram in the photo gallery that shows the schematic for the wiper circuit ( this site has great resources). I have a hard time figuring out how it works. I have the wiper motor in the car and two other wiper motor units. I have tried all three on the car. You can here the relay click but no motor movement. I have almost 12 volts coming to the motor on the blue w/ red. This closes the contact in the relay that is bolted to the wiper motor inside of the plastic case. When the concats close I don't have voltage on any of the other leads (blue w/ yellow or blue) I have also tried feeding voltage directly to the wires on the wiper motor (black w/ yellow, green, and red) I assume the motor uses the common ground on the case (black wire). I took the motor apart ( I do not recommend this) There are three brushes inside w/ springs. They come apart and you really can't reassemble it. The aramature will turn in the case but only with pliers, but you can't pull it out of the case. It appears bradded in. So rebuilding it or cleaning it up doesn't seem feasible. I worked on it all weekend. In the end I still don't understand exactly how the switch works, or the wiper circuit or how to test the switch to rule it out. I hate electrical problems... Thanks, Charles Man I'm glad I made that brief... Quote Link to comment Share on other sites More sharing options...
fastzcars Posted September 8, 2006 Share Posted September 8, 2006 Wipers> O.k. lets see if I can tell you how it works. The motor has 3 speeds. high medium and low. The black wire is your ground to the case of the motor. the blue(high speed) Blue/red(medium speed) and , blue/yellow( lowspeed) are your postive 12 volts from the relay and combo switch. So to test the motor out you should place your negitive line to ground and the positive to any "One" of the blue lines. Do not connect the battery for testing to two blue lines at the same time, you could blow the motor. As far as the armiture turning. (m I'm going off memory now) I think the motor has a gear reduction box on it and it would be hard to turn the output shaft by hand. Another thing to check would be your ground line to the motor case. Even though the connection on my motor Looked solid ,the connector was on the sheithing of the wire and NOT the on the actual wire itself, thus a bad ground. Look for that. I hope that helps. Quote Link to comment Share on other sites More sharing options...
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