I was searching for information regarding the TCC wiring for a 440T4 and noticed this thread had interesting information regarding this. Fieroguru mentioned on this thread https://www.fiero.nl/forum/F.../HTML/106842.html#p5 that we can wire the TCC circuit to the early style without problems. The interesting thing is that I have an older model trans (85) with the wiring described and it is not working for me.

I connected the Tan/Black wire to terminal D and the Purple wire to terminal A and as soon as I turn the key to the on position it blows the Gauge (10 amp) fuse. Any ideas why this is happening? Am I wiring this wrong?

Any assistance will be greatly appreciated.

[This message has been edited by vEnOm (edited 12-20-2010).]

You need to verify how your particular 85 transmission was wired (there are 3 different types and only one is similar to the 125C setup (lower right in picture).

Yes, it has the wiring as described in the image. The switches are the correct ones as well. The TCC is old but I tested it when I rebuilt the tranny, the torque converter is new though.

What puzzles me is the fact that blows the fuse right after I put the ignition switch to the on position. Am I placing the wires in the correct position? What about terminal B? Should there be anything connected to it?

Thanks for you input.

[This message has been edited by vEnOm (edited 12-20-2010).]

It sounds like you are hooking it up correctly (purple +12v to terminal A and Tan/Black ground to terminal D), but you have a dead short somewhere.

There should not be anything wired to terminal B or C. If you put +12V to these terminals, there is a very good chance of blowing a fuse as it is connected.

With the TCC connector disconnected, probe terminal A (both on the tranny and in the wiring harness) with a multimeter checking for continuity with a known good ground. Neither should go to ground. If either does, that is the portion that has the short.

Do the same for terminal D. Again neither should go to ground (the ecm supplies the ground to lock up the TCC), if either does then something isn't correct in this portion either (but wouldn't cause you to blow fuses).

[This message has been edited by fieroguru (edited 12-20-2010).]

quote Originally posted by vEnOm: Yes, it has the wiring as described in the image. The switches are the correct ones as well. The TCC is old but I tested it when I rebuilt the tranny, the torque converter is new though. What puzzles me is the fact that blows the fuse right after I put the ignition switch to the on position. Am I placing the wires in the correct position? What about terminal B? Should there be anything connected to it? Thanks for you input.

If you hook up TCC solenoid backward... Then Diode either has blown or acting as a short to solenoid winding. Blown diode shouldn't blow a fuse. Diode causes odd problems if blown. Diode blocks voltage surge for solenoid winding when main power shut off.

You should not blown the diode with key on... 3nd gear switch is open.

also ohm out pin A and trans case. If you have a short to case then you should see it easy.

------------------
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Fieroguru, Ogre, you are correct.

I did an ohm test on pin A from the trans plug to the trans case and it has 0 resistance. I did the same thing on pin D and it stayed the same, 1. So if I'm guessing this right, I either have the wires connected backwards in the trans or I have a short to ground on pin A. Correct?!

If the wires are connected backwards, can I interchange the wires in the plug as well?

[This message has been edited by vEnOm (edited 12-21-2010).]

If you merely swapped the wires inside the transmission, you should not have a dead short.

It is either a bad wire shorting to the transmission case, or wired improperly... like the wire from terminal A going to the 4th gear switch instead of the 3rd gear switch. The 4th gear switch is a N.C. switch that is grounded to the case. The 3rd gear switch is N.O. and isolated from the case - it provides continuity between the two ternimals when pressure closes it (at speed and the transmission is in 3rd gear or higher).

Time to pull the side cover and see what is up.

Fieroguru,

I have a question that you probably help me answer. Once I get the wiring fixed will the TCC engage in both 3rd and 4th? What if I remove the 4th gear switch and place the 3rd gear switch in it's place? That should give me TCC only in 4th, correct?

quote Originally posted by vEnOm: Fieroguru, I have a question that you probably help me answer. Once I get the wiring fixed will the TCC engage in both 3rd and 4th? What if I remove the 4th gear switch and place the 3rd gear switch in it's place? That should give me TCC only in 4th, correct?

Yes, if wired like stock, the TCC will be engaged in 3rd and 4th gear.
You can move the switch to the 4th gear port (make sure to plug the 3rd gear port) and have the TCC only lock up in 4th... this is how I would wire it if you were not using the ecm to control the TCC (like if you were using a 54psi switch from the govenor port - it would engage the TCC around 42mph)

[This message has been edited by fieroguru (edited 12-22-2010).]