SteveJ

And @Randalla's version works well, too.

The hazard switch can affect the turn signals, but it's less likely in this case since the hazards work. Just double check that the connectors are plugged in firmly on the hazard switch. As for wire colors, use them to find the wires on the dash harness/engine harness/body harness. Connectors should only be able to connect one way, so if a supplier did not follow the right convention, the wire should still go to the right spot. The BE section of the FSM has good (but not great) documentation of what wire goes to what pin on the connectors.

Hopefully you'll figure out what went wrong with the install. I won't be near B'ham until ZCON, and I would only have a scaled down toolkit with me. As for #1, whenever I encounter a new problem with my cars, I usually start with looking at the last thing I f'd with.

I'm not sure who drove the rubber bumper wonder. It might not have been a club member. One of our members sometimes shows up in an old Beetle, but that car was inherited. As for the multi-colored S130, that car is for mosquito control. Once he fires it up, the smoke kills those little buggers for at least 3 counties.

Suggestions Remove the relay kit and see if normal function is restored. Remove the headlight switch and check resistance across the terminals for the parking lights with the switch in off. Be more specific about the tail light relay kit. Do you mean the parking light relay kit that Motorsport Auto sells? https://www.thezstore.com/page/TZS/PROD/classic10l/12-4652 If it is the parking light relay kit, something isn't landed right. Drive 3 hours to my place for me to fix it. Standard rates apply.

I took the car out to the Georgia Z Club meeting tonight. With the warm, dry weather, there was a good showing.

14.5 is right on the money.

I suspected as much about the flasher and hazard switch. You saved yourself a lot of grief by reading my instructions carefully and re-checking. It can be a royal PITA messing with the hazard switch. You may want to consider ordering a lead set like this for your meter: https://www.amazon.com/gp/product/B0779V9H4F Another way to check the voltage with the engine running is to get one of these and plug it into your cigarette lighter: https://www.amazon.com/aceyoon-Voltmeter-Cigarette-Protection-Compatible/dp/B07QZS36F2. While it might not seem like a great tool, a similar product let me know the charging system on my 260Z was on its last legs.

That voltage is low. What is the voltage at the battery with the car running? Do you have someone who can work the gas so you can measure the voltage at 2500 RPM?

If your measurements are correct (Sorry, I have helped too many people, including engineers, who can't get proper measurements with a meter, so there is always a measure of doubt when I don't see it executed.), then you need to remove the hazard switch. I advise that before you do the process below, you pull and push on the hazard switch knob a few times and remeasure voltage at the turn signal flasher (with the key ON). To remove the switch Push and turn on the knob (counter clockwise) and pull the knob off. Be careful not to lose parts. (Been there, done that.) After you pull the knob off, you will need to unscrew the retaining ring. You may be able to use snap ring pliers to get at the holes in the ring. After you remove the retaining ring, you need reach behind the dash to disconnect the optical fiber. Then you have to look up new curse words to reach up further behind the dash and unplug the two connectors, probably with one hand (hence the need for the curse words). Pull the switch out from behind the dash. Go ahead and reassemble the switch after you remove it, so you don't lose parts. There are two connectors on the switch. One has 3 pins, and the other has 6 pins. I numbered them in this picture for easier reference. With the knob pushed in (Hazards off), pins 1 and 9 should have continuity. Also pins 7 and 8 should have continuity. If they don't, re-check that the shaft of the knob is fully pushed in. You may want to push and pull a few times to see if contacts are dirty. Z Car Source lists the 73 switches as available on a exchange basis for $85. Reinstalling the switch: Go back to your source for curse words. You will probably need to find some that will guarantee you a spot next to Satan after you pass. Reach up behind the dash with the switch in your hand and fish it through the hole in the dash. With the skill of a contortionist, reach up with your other hand and start threading the retaining ring. Fumble around blindly to find the 3 pin and 6 pin connectors on the dash harness. Utilizing all of the curse words you looked up in step 1, try to reconnect the connectors blindly with one hand. Having secured your alliance with the Prince of Darkness, attempt to reconnect the optical fiber so the switch will light up at night. (See the reference photo below of the lighter and hazard switch with the light source. Finish securing the retaining ring. Put the knob back in reverse order of removal. Test. Good luck.

When activated, the hazard switch will block the voltage sources for the turn signals and brake lights. However, if the turn signals come on at all, then that is not the problem. Check for 12VDC to ground at the turn signal flasher (driver side) when the key is on. If you have voltage on either side, you can rule out the hazard switch as being a problem.

Which end? If it's the end away from the panel, it's likely the water ****. See if you can take a picture. https://www.totalzparts.com/product/datsun-260z-280z-heater-water-****-control-valve-1974-081975-nos-oem/ https://zcarsource.com/rebuilt-vacuum-heater-****-for-heater-control-valve-for-the-1974-78-starting-in-august-of-1973-datsun-260z-and-280z/ (AC version)

It could be the watercock at the heater core. I sprayed mine down with silicone lubricant while I worked the slider back and forth. It moves smoothly now.

When tracing wiring go by the colors in the wiring harness. That is what the wiring diagram is based upon. The fact that the switch switched the colors doesn't really matter much as long as you keep the wiring harness colors straight. I don't have the spare time/energy to drive up to Chattanooga, but if you want to drive a couple of hours down to me, I will give you hands on training in using a meter to diagnose using my 73. The connectors are different, but the wire colors of the affected circuit is the same as your 72. Once you get the technique down, it should be easier to find the short.

What is the voltage at the battery when the car is idling? Like I said, the old mechanical flashers can be picky about voltage. I forgot to address the horns. When I was waking up my 73 after its long slumber, I tried the horn. Nothing. I took a dremel with a wire brush and scrubbed the contacts on the engine harness and the horns. (I also hooked up the horn that was disconnected.) Both horns worked with clean contacts. Other possibilities Horn relay The horn button isn't pushing the horn contact on the turn signal switch against the steering column. Fuse

If you have an old mechanical flasher relay, what @siteunseensaid is spot on. Over 20 years ago my 73 had the slow to no flash at idle. I swapped out the alternator and did the internally regulated alternator conversion. I never saw the problem again. Another way to resolve this is to change to electronic flashers. I bought this one for my Z cars after changing to LEDs: https://www.amazon.com/gp/product/B0811GTVH2. You have to add a ground wire to make it work, but you can adjust the flash rate, and it gives an audible click.

Are you sure it was 0 ohms from green/blue to ground? That would indicate a short between that connector and the fuse box. In other words, I would expect a fuse to blow as soon as you plug it into the fuse box. Go to the left side of the parking light fuse in the fuse box and check resistance from there to ground. Also make sure the back side of the fuse box is not making contact with the body of the car.

For the parking lights, the switch connects the green/blue and green/white wires together. In the fuse box, the white/red wire connects to the "high" side of the fuse. The green/blue wire connects to the "low" side. When everything is connected, you will have battery voltage on the headlight switch at the green/blue wire. When the switch is turned to position 1 or position 2, the green/blue is connected to the green/white. to send voltage to all of the bulbs. I suspect that you could see dim light in your parking lights when you bypassed the switch because there was enough current to flow through the bulbs as well as the short. If you jumpered the wire at the combo switch, you bypassed all fuses as the power for the headlights goes through the switch and out to the fuse box (That is the opposite of how the parking light circuit is wired.). If you saw 0 ohms from a wire to ground in the tests I described a few days ago, that indicates a dead short. Disconnecting the connectors in the passenger footwell was an effort to try to narrow down where the short could be. If the resistance went up after disconnecting part of the harness, you can reasonably expect that the disconnected harness is shorted somewhere.

No, you're not on the right track. When you jumpered over the red/white to the green, you bypassed any fuse protection outside of the fusible link. If you're not putting any current through the fuse, it won't blow. I hope you didn't have an electrical fire. Your description of the results are confusing. Are both wires on your switch green/white? The resistance between the switch and fuse should be almost 0. With 0.7 ohms, it says dirty connection. Having the other side of the switch be 0 ohms to ground indicates a dead short. Disconnect the 6 pin connector at the steering column. On the dash harness side of the connector, measure resistance to ground on the green/white and green/blue wires.

Post #3

Happy birthday, again, to @Mike

The benefit of the 16s is that you have a better tire selection.

What's your goal? Most people pick wheels first, such as Konig Rewinds at 16x7, 4x114.3, zero offset.

Pull the 20A fuse. Turn the headlight switch to off. Measure resistance (not continuity) from the left terminal of the fuse to each wire on the parking light side of the headlight switch. One wire should have about 0 ohms (probably the green/blue), and the other should have a lot more (probably the green/white). Measure resistance to ground on the wire that had the higher resistance in the first measurement. It should be low now. Unplug the two connectors indicated below and repeat the resistance measurement. If the resistance is still low, the short is in the dash harness. If the resistance is high, plug in the larger 6 pin connector and re-measure. If the resistance is low, start checking the front markers and the front side markers. Unplug the connector again. Plug in the small 6 pin connector and re-measure. If the resistance is low, start checking the rear markers and rear side markers. Let us know what you find.