Help with headlights

[Arne]

Christian, is it drivable in the daylight? Feel like driving down to Springfield later this week or this weekend? I bet we could track this down in fairly short order...

[zanthus]

yeah it is but I'd have to put all the body panels back on. I'll see if I can do that this week and let you know. But I don't have turn signals so thats could be a problem. Not if I took highway 99 down though.

[SteveJ]

No I dont and I can't figure out why. I've got power going into the fuse box and from the switch that turns the parking lights and head lights on but none to the switch that switches the highs and lows. I also have the Hazard switch disconnected because that needs a rebuild. Will that hurt anything?

Let's break this down.

1. You have high beams.

2. You don't have low beams.

3. If you tested the dimmer switch and didn't have continuity between pin 16 and pin E (hopefully you moved your dimmer switch back and forth to ensure you were putting it in the low beam position), your dimmer switch isn't working.

Disassemble the dimmer switch and clean it, or see if you can send it to Dave (Zs-ondabrain) for his cleaning and repair service.

[zanthus]

Now by dimmer switch I'm assuming that you mean the switch that turns the high beams on over on the turn signal side? I don't have continuity there. I have it coming from the other side where you actually turn the lights on at. And I have already cleaned the switch (many times) put it together correctly and poof still no low beams. I can run highs to my hearts content but somehow I don't think my fellow Oreginites would appreciate it.

[SteveJ]

Now by dimmer switch I'm assuming that you mean the switch that turns the high beams on over on the turn signal side? I don't have continuity there. I have it coming from the other side where you actually turn the lights on at. And I have already cleaned the switch (many times) put it together correctly and poof still no low beams. I can run highs to my hearts content but somehow I don't think my fellow Oreginites would appreciate it.

Your assumption about the dimmer switch is correct. Since you have attempted cleaning/repair, your choices appear to be

1. See if Dave can clean/repair it. (If you are confident in your skills, maybe it is beyond his abilities as well.)

2. Buy another switch. (New switches: MSA Black Dragon)

After looking at the prices, choice number 1 seems like a REAL bargain, unless you can find a good used switch from ZBarn or other place.

[Zenioric]

for those still following this post...i found the problem!. the large spade ground wire under the combo switch harness connectors (top of steering collumn under ignition lock cylinder) wasn't properly connected. the male spade was slid in between the outter female receiver, and the clear insulation 'boot' of the spade connection, thereby giving intermittent contact.

I´ve been working to solve that same problem for days.

Now, when I opened (for the first time) that "room" I found

that there the problem was! Now all the lights are ok. Thank you!

[zanthus]

I'm just confused how buying a new switch will solve my problem of not having continuity. I'm thinking that Ive got the power wire grounding out. Also on the fuse box it has a fuse for left and right lights not high and low. But the lights them selves are wiried stock for high and low not left and right. Where does it make this switch anyone know? I'm thinking that is where my problem is.

[SteveJ]

I'm just confused how buying a new switch will solve my problem of not having continuity. I'm thinking that Ive got the power wire grounding out. Also on the fuse box it has a fuse for left and right lights not high and low. But the lights them selves are wiried stock for high and low not left and right. Where does it make this switch anyone know? I'm thinking that is where my problem is.

It's simple. I asked if you had continuity at two points on the dimmer switch. You said you didn't. If the switch isn't making electrical contact at those points and you've attempted to repair it without success, it would be time for a new switch.

As for how the circuit is laid out, here is a simplified diagram. The fuses have been omitted, but they are on the red wire and red wire with yellow stripe.

Okay, so the image doesn't appear in a decent size. Try this link.

[Zs-ondabrain]

Not having read the whole thread, here's what I would do.

Make sure there is power from the fusebox to the combo switch.

Then check for power from the switch to the fusebox L+R headlight fuses.

The right headlight is solid red and the left headlght is red/yellow all the way to each headlight.

Check the T/S switches Hi/Lo switch for ground. Each headlights Hi beam wire is red/white and the lo beam wire on each light is red/black.

If there is no ground signal at the headlight plugs, on either hi or lo, trace them back to the hi lo switch on the steering column.

The headlight system is usually a stand alone system, powered from the fuse box, distributed by the fusebox. The ground system comes from a decent ground, to the hi/lo switch, and out to the headlights. Unfortunately for the 280Z's, I think the grounds make a few stops on the way. I could be wrong though.

Best bet is to get FSM and start tracing, the initial wiring colors are correct and their paths are correct. Start checking the plugs for power and ground with the switch on, flip it to hi beam and do it again.

I just can't understand why your Z is giving you so much trouble on such a simple system.

Tell me what you've done and what you came up with so far. We'll get this figured out.

Dave.

[Zs-ondabrain]

Great diagram but it's wrong. The red/white is the hi beam and the red/black is the low beam. Just an FYI.

Great example though.

Dave.

[Zs-ondabrain]

OK So I just read the whole damn thing and here's what I got.

As pointed out. You have Hi beam but no Low beam. This tells me that the combo switch works fine. As long as the headlight switch is on, there is power to the headlights for both HI and LO beam.

The HI/LO switch is the determining factor here. If you've torn it apart many times with the same results, the contacts could be bad and the solder could need to be reflowed. If it is at all possible, use your OHMs meter to check between the switch and the pin 16. you may have a short or break in the lowbeam wire.

If posible and it calls for it, replace it with a 14 gauge or 12 gauge (even better) wire.

Dave.

[SteveJ]

Great diagram but it's wrong. The red/white is the hi beam and the red/black is the low beam. Just an FYI.

Great example though.

Dave.

Heck, there was more wrong with it than just the wire colors being switched. Apparently the wire color switch happened about 7 years ago when I was documenting splicing relays into the headlight circuit. I pulled a wiring diagram off the net this morning since I didn't have one handy. I had an error in the layout of the circuit as well.

This should correct my previous errors.