No lights

[AidanDawn2000]

!!Disclaimer!! I am pretty much hopeless at all things electrical so there might be some stupid questions coming up

So I drove home last night, lights worked great. Next day, nothing! No headlights, running lights, tail lights, license plat light or dash light; not evan the little red one on the speedo
I have tried two different stock switches of unknown quality with no improvement. Non of the fuses are blown.
I have access to a multimeter but am not sure how to use it diagnostically.

Voltage regulator? Headlight Relay?

Does This look like a good replacement?

Thanks!

[pebbles]

Sorry for not knowing what year your car is , but 68 is different than 69-70. I think the relay only relays hi low beam. My guess is you have a power to the fuse panel or power from the fuse panel problem.

[AidanDawn2000]

Sorry. She's a '68 SRL.

[greydog]

You are going to need a wiring schematic. There is one in the Wiki.
You'll see power goes from the battery to the starter.
From the starter power runs thru a white wire to the A post on the fuse box.
Check to see if you have power at that terminal.
Set the multimeter to dc volts, select a range to encompass 12v. Connect the black (negative) lead to ground. When you you touch the red lead to the A terminal you should read a out 12v.
If no power at fuse box work back toward battery u til you find power or get to the battery.
Report back.
Dan

[msampsel]

What does the battery voltage read? You can get this with the process outlined above.

Check for 12 volts on both sides of the 30 amp fuse by touching the red pointer+ (multimeter) to the fuse housing and the black- to the ground or the battery.
It you do not have +12 volts or so on both sides of the 30 amp fuse (see diagram) you can
remove the fuse and check it for continuity. Set your multimeter on 20K or so ohms.
Touch the leads to each side of the fuse, should read zero ohms.

You can use a similar method to verify your switches are good. Use the diagram and test for continuity.
Should be him resistance (Ohms) when off and zerpo Ohms in the on position.

As mentioned it is unlikely the relay or the voltage regulator are the problem.
Unless the battery is dead, then it might be the vreg or the alternator.

http://www.311s.org/PDFs/wiring_02.pdf

[greydog]

As mentioned above, it's not your vreg or headlight relay.
if the car runs but has no lights, not even 4 way flasher) there are a very limited number of places that can cause the issue.
It's a matter of finding where you have power and where it stops flowing.
Check the battery first, then the fuse block.
Let us know what you find.
Dan

[AidanDawn2000]

Thanks guys! I will go poke around with the multimeter and try to find were it all goes bad.
I should mention that the car runs great and still has turn signals and break lights

[greydog]

Ok. The better (more specific) info you can give the better our chances..
So, do the 4 way flashers work?
By brake lights, do you mean theparking lights in the rear work (tail lights, brake lights (when pedal is applied) turn signals in the rear?
Do the front parking lights work? How about front turn signals?
No lights in the dash, no head lights (high or low beam) but everything else works?
Dan

[fj20spl311]

Are you sure none of the fuses are blown.
The power feed for the headlights is also the ignition, so that must be good.
Do you have power to the red wire at the light switch.
A test light is better than a multi meter for running down open circuits.

[Alvin]

Here you go Aidan,
from http://www.datsunroadster.com/SUB_SECTI ... lights.htm
REAR LAMP NOTE:
The 1963-67.5 cars used a 2-wire turn lamp and a 3-wire brake and tail lamp. The 1968-70 cars used four 3-wire lamps. The 1968 had four lamps lit when the taillights were on; but the turn and stop were on different lamps. On the 1969 and 1970 cars all four lights were used as tail, turn and stop lamps.

Just for fun (or more confusion)

[AidanDawn2000]

Thanks Alvin!
My car uses the four big lamps for tail lights (when headlights are on) and the middle two for brake/signal lights. Which is kinda odd because the result is that at night with the tail lights are on the brake/signals don't really work. I've never seen the little top ones light up.

[Alvin]

Thanks Alvin!
My car uses the four big lamps for tail lights (when headlights are on) and the middle two for brake/signal lights. Which is kinda odd because the result is that at night with the tail lights are on the brake/signals don't really work. I've never seen the little top ones light up.

The little "top" ones are reflectors. When we refer to top/bottom it is the two larger lights, not reflectors.

[AidanDawn2000]

I knew that (not)

[fj20spl311]

If your brake and turn signal are not bright, I would bet you have the running wire and brake/turn wires swapped or a bad ground.

Try swapping the wires on one to see if its dimmer. You can also take the light holder out and make sure the small wire is lit when the running lights are on. Running filament is on the left, stop / turn on the right.

[pebbles]

Thanks Alvin!
My car uses the four big lamps for tail lights (when headlights are on) and the middle two for brake/signal lights. Which is kinda odd because the result is that at night with the tail lights are on the brake/signals don't really work. I've never seen the little top ones light up.

My 68 has brake lights on the "middle" two, and turn sig on the bottom two. I dont think 68s share the turn/brake filament. IIRC Sports Imports has validated this in another thread.
As Phil stated, you have some testing to do.