Wiring up an A4LD OD without a computer.

[igiveup]

Hello

How does the tourque converter solenoid work. Does it power up to shut down the tourqe converter or power down? At the moment my 85 B2 is wired up brake switch to solenoid to ground. So when I press the brakes a lite on my dash lites up telling me there is power going to the solenoid. My shifter also has p,r,n,od,d,2,1 and I drive in d most of the time and if I am in od I will drop it to drive when under 80km/hr.

TIA
igiveup

 

[BrooklynBay]

The solenoid controls the fluid flow to engage the converter.

 

[MrShorty]

How does the tourque converter solenoid work. Does it power up to shut down the tourqe converter or power down? At the moment my 85 B2 is wired up brake switch to solenoid to ground. So when I press the brakes a lite on my dash lites up telling me there is power going to the solenoid.

Not quite sure what you are saying, but, if I understand correctly, I'd say neither.

For most of the "output" solenoids (3-4 shift, TCC, EVR, fuel injectors, CANP, etc.), they are wired in with a constant +12 V power supply, and the computer acts as a ground side switch. It's been a while since I've tinkered with mine, but I believe it is set up so that the computer closes the switch when it wants to engage the TCC. Note that TCC lockup is supposedly hydraulically inhibited in 2nd and 1st gear, so even with the switch closed, it won't lockup until the transmission is in 3rd or 4th gear.

Does that help?

 

[Maniak]

MR shorty is correct.. There is a common red (power) wire going down to both the TCC adn the 3/4 solenoid. The ECM grounds the other side of the solenoid to make it work.. It not really grounded, the ecm closes a switch when it "should" control the solenoid..

From what I've read/seen.. do not ground out the solenoids as the power that is sent through the solenoids comes from the ecm.. and if you ground them it may burn the ecm..

In theory, if you supplied your own power (I can't remember if its 12 or 5 but I "think" its 12) to the solenoid and then grounded out the other side yourself you could control the 3/4 and tcc lockup w/out the ecm.

~Mark

 

[igiveup]

Hello

I have an idea. I was thinking of using a relay.
http://www.bcae1.com/images/swfs/relay.swf
I was thinking of running power thru 87a on the relay then when I press the brakes it goes thru 87 on the relay.

When I start the B2 the tranny is ready for tcc. Touch the brakes and it shuts off the tcc lock up. Also I will get a GM vac switch for low vacuum.

Do you think it will work?

igiveup

 

[MrShorty]

I was trying to understand why you wanted to do this. Your signature says you have a durasparked '85, so I've finally gathered that you've removed all the computer controls from the engine, is that right? Now everything starts to make sense.

As I indicated, I'm reasonably sure the circuit is complete to lock up the TCC, and a break in the circuit should unlock it (assuming transmission in 3rd or 4th gear). So I expect you should be able to make it work. Two switches in series: one that is closed when the brakes aren't on, and one that is closed when engine vacuum is high. If I'm right and you are trying to make it work after removing the computer, then it shouldn't matter whether you put the switches on the power side or the ground side of the circuit.

 

[igiveup]

Hello

How do I test the TCC solenoid when its in the transmission with out having to take the pan off. Can you hear it click if its powered up the powered down?

igiveup

 

[BrooklynBay]

Test the continuity at the connector to start. It should be 25-40 ohms. Applying power is only a click test.