Hello,

We just upgraded our alternator to a ZX alternator and upgraded our headlights to H4s. Unfortunatly now our turn signals and horns do not function.

I replaced the flasher unit and still have nothing. The 4-way emergency flasher works as do our headlights, running lights etc.

About 2 years ago we bought a brand new turnsignal switch and it worked fine before this point. I also took off the column covers and uplugged, cleaned and re-connected the switch to be sure it was ok...it looked and preformed as new...but still no signal lights!

The horn clicks and makes a faint noise but thats it.

When we upgraded to a ZX alternator we had the voltage regulator removed and in its place a diode was installed.

Has anyone had similar issues with this conversion and does the headlight relay upgrade from Motorsport work to resolve this?

Very frustraiting since I thought the new alternator and headlights would make things better...they seem to have complicated them


Thanks,

Colin

_________________
Currently Own - RED 70' 240Z, GREEN 72' 240Z

First Owned - New 72' GREEN 240Z
2nd Owned - Used BLUE 74' 260Z

Colin,
I'm not much on auto electrics but your recent upgrades may be the cause of your problems. Recall that all the lighting current runs thru the fusebox and the switch and places a very heavy load on the wiring and contacts. I suspect you have fried the switch components with the additional power of the new alternator and the increased load of H4's.

While shopping for parts for my project, I came across this item at MSA that seems to both explain and remedy the problem. It specifically addresses your H4 upgrade. This is a planned upgrade for my car.

http://www.thezstore.com/page/TZS/PROD/SRC19/12-4651


Regards,
Jim

_________________
Jim Arnett
Richardson, Texas
HLS30-15320 12/1970 (original owner)
ZCON 2015 Gold Cup - Street Modified class

Hi guyz~

I just completed this same swap-out at Vinny's, with almost no problems. We followed the procedure recommended in Bryan Little's DATSUN Z GARAGE website and it came out great. We used a diode tho, not a fuZeable link. I now have 90amps of searchlight brightness available, and the external regulator has been removed from my enginebay.

I would suspect a fuse first, then a disconnected wire second. When we were changing my system one of the fuses blew as soon as we connected power, which led to a moment of confusion until we checked the fuse box. Be especially watchful of that 20amp "common" fuse, which can take several other systems with it when it fails.

You and I are doing essentially the same things to essentially the same cars. We should stay in closer touch.

Frank

Hi Frank,

Actually Vinny did the install. You are correct it was a diode not a fusable link

The horn fuse was blown so I replaced it with a spare. But still nothing from the turn signals. Horn still sounds very faint...just clicking. All the other fuses were fine.

I looked over the connections in the front of the car and cleaned them and reconnected them. Also Vinny put in a new flasher for the turn signals and it does nothing.

Did you do any upgrades to your harness for your H4s?

If the turn signal switch is fried can I tell by looking at it? All the wires and solder looked up to snuff.

Thanks,

Colin

_________________
Currently Own - RED 70' 240Z, GREEN 72' 240Z

First Owned - New 72' GREEN 240Z
2nd Owned - Used BLUE 74' 260Z

I happen to have some unusual experience with the 240Z horns!

Mine were so corroded when I got my car back, they looked like two barnacled clams! I sandblasted both of them (even the diaphragms) and they worked great again. I flat-blacked both of them and they continue to work very well. If I recall yours, they're new or refurbished?

If yours are clicking, power is getting to them. I would dismount one (they're a pain to reach while the front end is intact) and turn the adjuster screw on the back in each direction, testing as I went. Also, while one horn is off the car (or at least disconnected), I would try the other one. They're hooked in series, so if one is 'restricted' (i.e. "turned down"), the other might suffer also.

If you dismount both, you can run a test wire directly from your battery positive terminal to the power screw on the horn. Touch the horn to a clean ground briefly to see when the power is set right. (BEWARE of heart attacks when you finally have it right the first time! )

If they work in your hand but not on the car, I would suspect a faulty ground (such as too much paint where the horns are mounted, insulating them from a good ground), or faulty wiring / connector. Make sure all plastic connectors are pressed together firmly, so good contact can be made.

If none of that works (I'll be surpriZed if it doesn't), try swapping-in a known-good horn from another Z as a circuit tester.

Frank

I thought it meant that perhaps not enough power was getting to them.

If they do work again might that help with my signals? ....fingers crossed.

I did some research on Motorsports website and they actually make a plug with a diode in it that plugs right into the old voltage regulator plug off the harness...bummer we had ours cut for the diode...

Anyway...they also make a "plug and play" headlight relay for H4s that helps prevent fuse and switch burn out....we might be purchasing that one as well as one for the parking lights.

_________________
Currently Own - RED 70' 240Z, GREEN 72' 240Z

First Owned - New 72' GREEN 240Z
2nd Owned - Used BLUE 74' 260Z

I have ordered that wiring harness, but it hasn't arrived yet (back ordered). I am running the old harness until then, but sparingly. I've heard stories of total melt-downs with really bad old harnesses, after upgrading the alternator. Vinny was careful to pull the old harness and blast every connection clean, so at least it's in "like new" condition for now. But I'll still feel better when the new, heavier harness comes in.

I also ordered one of those nifty replacement fuse boxes MSA offers for the old 240. They use double bladed bayonet fuses instead of the glass tube fuses, and the terminals are brass rather than aluminum. All connections are heavier and one whole bank shares the current load, instead of trying to push all the current thu one little connector on the original fusebox.

Hi Frank,

Is there a way to test the turn signal switch to see if its getting power? Can I just touch it with one of those electrical light-up testers?

Have you replaced your turn signal switch?


Thanks,

Colin

_________________
Currently Own - RED 70' 240Z, GREEN 72' 240Z

First Owned - New 72' GREEN 240Z
2nd Owned - Used BLUE 74' 260Z

Yes, any circuit except the secondary ignition (high voltage) sparkplug circuit can be safely tested with a test light. None of it is more than 12v.

Make sure the key is ON, and the indicator lever is activated for that side. Test the 4-way flashers at the same time. If you show NO current at the end of the circuit, work your way backward thru the wiring harness to the next plastic connector. Pull that open and test there. Keep that up until you eventually find power. You know you're good to that point, and your problem is PROBABLY immediately ahead of that point.

ALSO ~ if you have a burned out bulb on either side, that side usually won't work.

No, never had to change mine out, but my right-turn signals require a
"stronger" pull on the lever than the left side does, for some reason.

Sometimes things just break by sitting. Sounds like the horn is getting a signal, but probably all corroded inside. Turn signal contacts are probably corroded as well. I had to clean those in the past, and things then worked.

I'm coming in on the tail end of this thread....

I can't see how changing the alternator could have affected the turn signals or horn. The ZX alternator puts out 14.58v just like the 240Z one, it just that it regulates the power more efficiently (internally) instead of using the old regulator on the firewall...the car doesn't know the difference. If other accessories are working then 12v is hitting the fusebox properly.

But the problem with the 240 is that not only is everything routing through the fusebox, but the headlights and lamps all route through the switch on the steering column stalk too. As a result it's common to have to resolder joints on the headlight switch stalk and clean out the built-in contacts. The MSA relay makes a huge difference as it routes the full alternator power to the headlights. Mine went from yellow to white light.

If I were you I would take off the plastic clam shells that cover the headlight switch and inspects the wires, and unplug and replug the plastic plug from the rear of the headlight switch. I suspect its a grounding problem.

_________________
Bryan Little
Datsunzgarage.com

1970 240Z - enhanced F54 L28 w/P90, Weber DCOEs, 4:11 R200, Nissan T5 5-speed