for those of you who dont know... ive converted my car from tpi to carb, i have an 89 trans am GTA 5.7L. since hacking my wireing harness, several things dont work. ive managed to wire up most of it, but i cant get my heater fan to work. does anyone know if mabey i hacked the power supply? i cut every wire going directly down into the passangerside fender.

and also, that little small white wire comeing off the alternator... i was told to wire that up to a "run" ignition source so that it can turn on and supply power to the battery. it worked ok for a while, but now it stopped. whenever i turn on the car its not chargeing. i tryed wiggleing every damn part of the wire and nothing works. i did a really good solder job on it too. is it possible i was suppost to hook it directly to the battery? it seems stupid to make an alternator "turn on" it should just run when the belt turns. will it drain the battery if i just leave it always "on"?

 

There should be two small wires on a plug at the top of the alt, you need them both for it to charge. The white ties to 12 volts ign on, the tan wire is the alt sense lead. it normally ties into the same 12 volt circuit as the heater blower motor. it senses voltage drop and adjusts alt output accordingly. i would suggest getting a Chilton manual for wire coding to repair the heater motor control. browse the sire here, I am pretty sure there are diagrams if you don't want to but a book.

 

why would the "tan" wire tie into the heating system? mines pink by the way

 

The sense wire goes to a point in the vehicle with the most voltage drop. Usually the blower motor or something with a heavy current draw. They do this in order to keep the voltage around 13 volts in the circuit with the most voltage drop. Remember you have resistance in the vehicle wiring and throw a heavy load like the blower motor the voltage may drop below 12 volts. They sense at this point and the alt adjusts itself accordingly. I loked at mine, can't tell what actual color it is. In reality you can tie that wire to any point you want, some guy's just loop it back to the lug on the rear that goes to the battery. By tieing it to a point in the vehicle as described you will have a more stable voltage to the accessories in the car, but it's up to you.

 

right now i have mine soldered to a wire going from the positive terminal to the starter. when it was like this, it worked for a little while and then it stopped. now my alternator doesnt even seem to work, the voltage meter is always below half and slowly declines as the car is running. my heater fan doesnt work at all, im guessing i have to do some major wireing under the passanger side. only problem is, i dont know wich wires are useless and wich arent. wireing diagrams dont seem to help me at all because i dont know wtf some of the terminology means. for example... solid state? i could spend countless days learning it but the fact is, after im done wireing up this car, i will probly never use that knowledge again. isnt there just one solitary wire that i need to connect to a power source to turn the fan on? right now i dont really care about the different power settings, or relays, all i want is the fan to work so i can defog my windows so i can drive to work in the morning. anyone who has done a tpi ->carb conversion must know what im talking about. my speedometer doesnt work either by the way i do appreciate your help though, you have given me a few ideas that im gona try as soon as those jackasses at the body shop decide to finish off my car so i can take it back home.

 

look at the heater control swiches on the module. brown wire is 12 feed from 25 amp fuse in fuse panel. a second brown wire should come off the same switch assy and go out to the engine compartment. that goes to the resistor on the blower box. there should be a relay near that area also, thats the high speed blower relay. You can put 12 volts on the green wire at the realy socket and the blower should run at high speed. The resistor is used for the slower speeds. if the plug is on the resistor follow the colors to where they are cut and splice wire(correct size) to the mating colors on the heater control switch. if its not hacked too bad that ought to get it working. if i had it here it would take a few minutes to get it working, its hard to do it over the net. Keep me posted, Dan

 

well, i have my car back now, and i still cant get that alternator to charge my battery if my life depended on it. my alternator cant be fryed, its brand new. but unfortunately i lost all the papers that came with it so i doubt i could take it back. its "possible" that my plug is garbage because my rad hose is resting right on it and may have bent the wires off inside the plug. but who knows..... im gona try some last minute things to it today (ie. hooking both wires up to the battery directly) this is a really annoying problem....

 

I think you are confused, I read your other post. You have Two wires on the alt plug(forget colors at this point). One should be heavier guage than the other. The heavy one gets tied to ign on 12 volts, the other is a sense. Just tie the sense to the lug at the back of the alt that has the heavy wire going to the battery. Forget the blower motor thing, the sense does not go to it , it ties into the fuse panel at the same point that FEEDS it 12 volts. Don't even worry about it, just tie it anywhere even to the other wire if you want. In fact you may not even need it depending what regulator you have in the alt. On the CS series alt you can use as few as 2 wires.

 

holy crap. so all this time i had it wired totaly backwards. i swear someone told me a while back that the little wire goes to an ignition on source, just like the relays have the little wires to turn them on, and the big wires to connect power. oh man, im gona go try that out in a few minutes and see if it kicks in this time

 

unfortunately the heater fan is a no-go. i spent hours testing every single "loose" wire under hood and under dash, and nothin seems to do the trick. i had some relays before that were mounted on the drivers side wall. but i thought they were useless without an ecm? one is an maf relay, the other is a burn off relay or something right? there is a really tiny relay that apparently controls my fog lights that i thought may have been it but nope.... i think all my relays are pretty much spoken for, none seem to be non-funtional. is it possible that the heater fan relays are under the dash?

 

hmm... ok i totaly didnt expect what just happend. yeah my alternator works now, BUT it wasnt the big wire that needs to be connected to a power source, its the small one. for some odd reason i cant connect the small one to any other power source other than the positive battery terminal or the wire comeing out of the alternator itself (wich leads to the battery). if i connect it to ANY other power source it wont come on. strangely, the wire i have going from the positive terminal to the starter wont turn on the alternator. wtf is with that?? also, the alternator works GREAT, that is untill i hook up the fat wire to something, then all the lights start going dim, then bright, then dim.... you get the idea. it actualy makes it worse. currently i have the small wire going straight down to the wire coming out of the alternator and now my car seems to produce a perfect 13 volts (is that normal?). will this drain my battery if the alternater is always "on"? also... why is the volt meter wire comeing OUT from the dash and into the engine bay? it seems to need a ignition activated source to turn on, wouldnt the closest place be near the ignition? im guessing if i just hook this wire directly to the battery it will always display the voltage causeing a slow drain right? or is this drain so slow that it wont matter?

 

Your blower has only one relay (for high speed) and should be located in close range to the speed resistior thingy...

 

i tryed everything with that relay, and those wires. as far as i can tell, that relay is dead, and those wires power the a/c stuff some how with the relay dont they? but ill check it out again tomorow (as if ive got anything better to do....) thanks for the input deadbird (pics make explanations alot easyer on the brain)

 

The heavy gauge wire on that relay (sometimes red, some purple.. mixed..) is direct power from the battery to the blower motor. When the switch is place on 'high', it powers the relay and powers the blower motor off the starter direct.

If I remember this right, the 'A/C htr' (something like that..) fuse/circuit in the fuse panel is powered from the ignition switch, (have you checked the fuse by chance ?). Turning the switch to any speed should at least show +12v power on at least one of the wires at the resistor thingy. I can't remember speed to wire color except I think yellow is 'low' and the orange should have +12v at the relay when the switch is in the 'hi' position (key on, fan switch in 'lo' position, +12v outside at the resistor on the yellow wire.. and so on). I'm starting to question if I'm even making sense now lol
If you're not getting +12v on the input side of the resistor, then power is either not getting to the switch or the fan speed switch is broken.

 

please proceed to the next message

 

trust me, i check my fuses every day after doing wireing work, the only one i have managed to fry is the "crank" fuse wich doesnt seem to have affected anything at all. basicaly what your saying is i have to turn the heater to high and THEN apply power to that relay?

 

Lol.. getting late ?

When you turn the fan switch to hi , it should send +12v from the switch to the orange wire on the relay (the other small gauge wire, black, is a ground). One of the heavier gauge wires on that relay is constant +12v and is wired (should be) direct to the main lug on the starter. When the relay closes, the juice from the starter passes thru (the relay) and powers the blower fan direct +12v.
If you have a voltmeter, at least 1 of the wires on that blower relay should have +12v on it at all times and, with the key on, fan speed switch on 'hi', there should be +12v on the thin orange wire as well.
Even if there's no power on the heavy gauge wireat that relay, the fan should still work on the lower speed settings, it just won't work on high.
If there's no power on the orange wire, the fan speed switch might broken and the voltage isn't passing thru it or, the whole circuit is bad somewhere.
If you check for voltage at the fuse (pull it out), with the key on, there should be +12v on at least one side of where the fuse plugs in. If there is power, then it betters the odds the switch is broken.

 

technicaly what your saying should work, but it doesnt for some reason. there is juice flowing through the relay and down into the pannel, through to under the dash, but there is no effect no matter what setting the fan is on. i noticed that some of the wires are ground wires (sparks flew out of them when i applyed positive power) so mabey i have to ground these?

 

oh, and as for the whole circuit, i think its safe to say that its toast. ive hacked and soldered so many wires now that no wireing diagram in the world could help me now. mabey i can borrow my friends digital camera again and take some pics of the wires under the hood and under the dash for ya. that might make the situation a little easyer to understand.