I have it all in and wired... I think but i.m getting no reading on the tach. I have a 5K linear potentometer, is that the correct one? Is there any way to bench test the tach to see if I have it hooked up right.
------------------ 86 SE Convertible 3800sc 4t65e HD.
[This message has been edited by Tweeder (edited 02-02-2014).]
This is how I have mine now. My board is a little different than yours. You can see where I had the one wire before. The one I left alone(the one that has the two pins side by side). As it looks like they are joined. Is that correct? The way I gave it now still doesn't work. Not sure if it's my wiring or the potentiometer.
------------------ 86 SE Convertible 3800sc 4t65e HD.
That's how I originally had it wired but I changed it to match yours. But like I said, our boards are a little different. I will order another potentiometer, the person who ordered it for me screwed up. Does it matter what kind or potentiometer? I see a clarostat, audio, linear, or just as long as it's a 1m ohm?
------------------ 86 SE Convertible 3800sc 4t65e HD.
[This message has been edited by Tweeder (edited 02-04-2014).]
I just went to my local electronics wharehouse and said I need a 1 Meg Ohm Pot. I think linear is for audio. But it shouldn't matter, Linear just means what the ramp of the increase in resistance does when you turn it up.
Is there a Frys electronics around you? They would have something.
Edit; Im pretty sure the only difference in mine and yours as far as our mod wiring goes is that the older tach like yours has a different map sensor input (Green wire) The Pot goes in the same place.
[This message has been edited by hercimer01 (edited 02-04-2014).]
I just went to my local electronics wharehouse and said I need a 1 Meg Ohm Pot. I think linear is for audio. But it shouldn't matter, Linear just means what the ramp of the increase in resistance does when you turn it up.
Is there a Frys electronics around you? They would have something.
We have no electronic stores near me, I'm at the end of a road way up north. I'll have to order it online. I'm thinking this?
Edit; Im pretty sure the only difference in mine and yours as far as our mod wiring goes is that the older tach like yours has a different map sensor input (Green wire) The Pot goes in the same place.
Earlier one like you have and the later one like I have at pretty much the same for what were doing. The first two pics show the earlier Tach Mod. The later one there are provisions for a spot R14 resistor that was never installed. This is where the trimmer pot goes on mine.
E1 and pin5 of the top chip are where the trimmer pot goes. Remember you are only using the middle leg of the trimmer pot (or wiper) and either one of the other legs.
The micro chip on the late one has been clocked differently but the foil runs still go to the same legs on the chip. And the cut would be the same.
SCCA FIERO
hercimer01
[This message has been edited by hercimer01 (edited 02-10-2014).]
Hers how the potentiometer is soldered to the board. I tried moving the wire out of the way to get a better pic but it broke off. It looks like it broke off below the board so I filed it down in hopes that when I re solder it will make contact.
------------------ 86 SE Convertible 3800sc 4t65e HD.
The yellow circle shows where it looks like it may have been shorted to ground on that foil run.
The purple circles show where the trimmer pot should be soldered. ( same as the leg on the chip, just easier to deal with.) I can't tell if you cut the foil run
The yellow circle shows where it looks like it may have been shorted to ground on that foil run.
The purple circles show where the trimmer pot should be soldered. ( same as the leg on the chip, just easier to deal with.) I can't tell if you cut the foil run
Now I'm confused, I have the older style from what I understand. Shouldn't I have it wired like you have it in the first pic? That's the way I had it initially. Or just do it the way you have it in the second pic?
------------------ 86 SE Convertible 3800sc 4t65e HD.
