Positive and Negative on the printed circuit board

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i used a 9 volt battery with wire leads ( like out of an old radio) to check + and - there is more then one ground @ the plug find the + and - on the led first if they are not non polarity then install the led in the socket and touch the leads to the plug socket see if the it lights i have a 71 and i think i remember the - is on the lower part of the socket you can fallow the curcuit to the sockets

 
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Thanks NailPounder and EBStang. That's perfect. I had did a little trial and error on the left hand side and had figure the outside line on the board was positive. But I had sent off my clock from the righthand side to Rocketman to add a tach and I am waiting for it to come back. I did notice that my fuel light did not work either way and the stock bulb seem to be real hot - when I took it out. I am thinking that it could be because the right side of the printed circuit was just flopping while I plugged the plug in last night in the dark garage. This will allow me to screw all of the bulbs in before I put it back in the dash.

 
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some pictures for a '73:
I can comment directly on this as I have also installed a Rocketman tach with idiot light along with Elite series LED's The result was very satisfactory and I retained the blue domes after a good cleaning.

PLEASE NOTE: there is/was a mistake that I pointed out to Hi-Po. The ALTERNATOR socket is marked in the wrong position, should be the bottom right socket. not top right as shown in the Elite instructions and this MUST retain an incandescent bulb or damage to the alt circuit can result. This why there are only 4 red bulbs in this kit. The Extreme series LED's bought previously had 5 red bulbs and did NOT show instructions regarding the ALT bulb. Hi-Po Parts are going to redo these instruction for all series of bulb systems. Hence "is/was"

Also not mentioned is the fact that you will need a Hi-PO GROUNDED ELCTRONIC FLASHER or the LED's in the turn signals won't work. I bought a regular electronic flasher and found out the hard way. I still have incandescent bulbs in the turn signals, which work fine, just not as bright.

If you have a full gauge cluster, the Alt light issue won't apply, but the flasher unit will. Why they don't tell you in the instructions is another "item" they missed. Hopefully it has been corrected by now.

Hope that helps.

 
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Thanks EddyW - the standard cluster with clock is an exact match. I will not replace the turn signals or the bright light (running red horse) - which I think is the tape piece attached to front of the cluster. But I did had problems removing the blue pieces (they were very hard and did a little damage as I tried to take them out (the little clips that hold them in broke off. I want to change take them out on the clock/tach side of the cluster when it arrives but - I am thinking about using my Dremel to help. I got an Email from Rocketman today saying the my gauges are on the way back. I got my Hipo Elite green LED lights in today.

 
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Stanglover, thanks - someone posted, earlier, not to put an LED in the lower right position and the chart is showing the upper right position. But I only took out 4 bulbs and there are 7 positions, therefore the other two along with the alternator position will not have a bulb - is that correct?

I am thinking the other positions were for the idiot lights - which I do not have (I have the center console gauges)

 

midlife

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The incandescent bulb for the alternator indicator light is required, as the resistance of the bulb (higher than an LED) is needed for the circuit to work correctly.

 
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Midlife - checking my old circuit board closely I can see that "with the clock" the two places on top and the one place on the lower right did not have anything in them. The other four positions had bulbs.

Are you saying that when I add the tach instead of the clock - I will need to add a bulb in that lower right position?

 

midlife

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Midlife - checking my old circuit board closely I can see that "with the clock" the two places on top and the one place on the lower right did not have anything in them. The other four positions had bulbs.

Are you saying that when I add the tach instead of the clock - I will need to add a bulb in that lower right position?
You're talking about the clock cluster housing, right? The two bulbs on top are the oil pressure and temperature sending unit indicator lamps. The lower right socket is for the alternator indicator lamp. If you have the center three gauge cluster and no tach dash, those sockets may be unused...I've not seen that dash cluster configuration, but I know it exists.

 
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Stanglover, thanks - someone posted, earlier, not to put an LED in the lower right position and the chart is showing the upper right position. But I only took out 4 bulbs and there are 7 positions, therefore the other two along with the alternator position will not have a bulb - is that correct?

I am thinking the other positions were for the idiot lights - which I do not have (I have the center console gauges)
So, you have gauges and a clock, no tach? Are the gauges factory? I assume they are as the clock has no idiot lights. Back then, there were some strange combinations that really make no sense to us today.

Also, I assume you have the circuit board that would also be used for idiot light, (top one pictured for Elite series LED's in Eddyw's post) if so, you would be correct and only use bulbs where needed. There would be no alternator bulb as you have the gauge. If there was no bulb in that bottom position, do not put one in (obviously). The red high-beam light is OK with an LED (red)

You are correct in saying there was a post before on this. I had posted and midlife also correctly commented on the Alt socket issue. Hope Hi-PO Parts have corrected that by now!!

As I mentioned, I wanted to keep the original hue for my instrument lights. I was not happy with the Extreme set I bought earlier, still not bright enough for my liking. The Elite LED's work great and now I can actually see my dash at night.

I'm sure you will enjoy your choice of green lights, but please let us know the outcome.

Geoff.

Edit note; TIP. When you go to wire in your new Rocketman tach, use bullet type connectors in the wires about 8" or so from the tach and add these connectors before running wires and installing the tach. (trust me it's way harder if you don't!!) That way, you can easily remove the instrument pod as and when required. MAKE SURE you have a good clean ground on the black wire. Solder the connectors as well. I used a Butane micro-torch and color keyed heat shrink over the terminals for easy reference.

 
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Thanks. I am kinda new at this. I will try to post some picture of where I am now.
Sounds good. You shouldn't have any problems. Just take your time. When you come to re-insert the plug in the circuit board socket, which can be a bi***, check that all the copper strips are clean and in place and secure. They can come loose and get out of place. I had this issue, caused some head scratching till I figured it out. A dab of crazy glue fixed the problem. Clean any excess off after it's dried.

Good luck with it.

 
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Mister 4x4

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So, you have gauges and a clock, no tach? Are the gauges factory? I assume they are as the clock has no idiot lights. Back then, there were some strange combinations that really make no sense to us today.
Yes - that is a factory option, found on the Mach 1s with the center 3-gauge cluster, but didn't have full center consoles with clocks. That's why Rocketman sells two different tachs for our cars - 1 for the "idiot light gauge," and the other for the "clock." The only warning light is the 'BRAKE' light.

Here's mine (when I first bought it):

attachment.php


 
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So, you have gauges and a clock, no tach? Are the gauges factory? I assume they are as the clock has no idiot lights. Back then, there were some strange combinations that really make no sense to us today.
Yes - that is a factory option, found on the Mach 1s with the center 3-gauge cluster, but didn't have full center consoles with clocks. That's why Rocketman sells two different tachs for our cars - 1 for the "idiot light gauge," and the other for the "clock." The only warning light is the 'BRAKE' light.

Here's mine (when I first bought it):

attachment.php
Interesting. Like I said though, Ford did some pretty weird stuff back then. No rhyme or reason to their thinking. Keeps us guessing though doesn't it!!

 
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