1bigcam

iTrader: (9)

anyone have a wireing chart for a brake switch and relay set up. i have a wire off my stand alone harness for tcc i think its called that i was told the best way to do that is to use a relay thanks mike

Pocket

iTrader: (22)

http://www.lt1swap.com/pictures/16_a...amp_switch.gif

It required 12v IGN and open with the brake depressed. No relay is required

1bigcam

iTrader: (9)

problem is my stock miata brake switch works like a nitrous botton when its pushed it supplys power to lights, i was told some how i could wire in a relay so it can also take power away from the tcc wire but still remain a normal brake switch ???

frito1

iTrader: (12)

I'm about ready to get a brake switch w/cruise for a mid 70's chevy truck. It will have two switches in it. One is NO and one is NC. One for the brake and one for the cruise. Use the NC (cruise side) for the TCC signal.

G-Body

iTrader: (4)

Standard bosch style relay.

terminal
85 - ground
86 - to brake wiring on car.
30 - to IGN + 12v
87a - to tcc wire/PCM

1bigcam

iTrader: (9)

86 to what side of the break switch? thanks very much thats what i was looking for

G-Body

iTrader: (4)

To the side that connects to the brake lights

1bigcam

iTrader: (9)

that wont make my brake lights stay on will it?

G-Body

iTrader: (4)

Nope, should not affect the brake lights at all.

aknovaman

iTrader: (7)

Check your Miata dot net PM I sent.

TomM

iTrader: (56)

If your Mazda uses the 3/8" barrell type plunger switch, you can use a brakelight switch from an 82 Monte Carlo with cruise control, has one set normally open, and one set normally closed contacts, which reverse themsleves when you step on the brakes.....

T,

aknovaman

iTrader: (7)

http://www.700r4.com/tech/tcc/relay_.../diagram.shtml

Use either diagram but instead of hooking it up to the trans, the wire goes to the PCM blue connector pin 33 (purple wire).

Pocket

iTrader: (22)

Auto PCMs require both the brake switch to PCM wire and the PCM to trans TCC wire. There is no choice. Leaving one off will prevent TCC control and burn up the trans in short order

camaroboricua

iTrader: (23)

Bringing this back up from the dead. I have the same issue, how did you get it to work?

Also, where is the PCM to TCC wire located?

camaroboricua

iTrader: (23)

I used just the relay and its still not unlocking. I see two wires in the diagram above for PCM to TCC. which one do I tap into and what does it need? (12v? or what)

sdetweil

If you are using the standard 4L60e tranny harness, then u only need one wire to tell the PCM when u are stepping on the brake.. blue connector, pin 33.

a normal 5 pin relay has 2 outputs.. 85/86 switch the relay on. 30 gets switched to 87 or 87a.

87a is connected to 30 normally (Normally Connected, aka NC)
87 is connected to 30 ONLY when 85/86 are energized.. (Normally Open, aka NO)

the key thing is 87a becomes UNCONNECTED when 85/86 are energized..
so 87a and 87 toggle.

SO, you connect 87a to pin 33 of the PCM. so power is supplied ALL THE TIME, EXCEPT when the brake is applied (85/86 are energized), then it is disconnected.

the rest is up to the PCM..

now, in my case, I will NOT have a PCM controlled tranny (700r4), so I have to wire it (87a on the relay) to the wire on the tranny directly (like the bowtie overdrives drawing)

Sam

the_merv

iTrader: (88)

I only have Blue 33 pinned on my S10 and I have no issues.

12v Ignition to the Switch on one wire, the other to Blue 33. The PCM needs that 12v Signal from the Brake Pedal to lock the Convertor. Step on the Brake, signal off.

Like mentioned with the Relay, 85 is ground, 86 is off of the 12v Brake Wire going to the lights, 30 is 12v Ignition in, 87a is to the Blue 33 on the PCM. Step on the Brakes, 12v goes to the lights, energizes the Relay, stops the 12v to the PCM and Convertor.

Pocket

iTrader: (22)

You left out the TAN/BLK wire from R42 and your converter still locks up? I find that hard to believe since it directly controls the lock up solenoid

http://www.lt1swap.com/pictures/16_a...amp_switch.gif

the_merv

iTrader: (88)

Well ofcourse that is in there..that's factory in the Auto Harness. I guess I misread your post.

However, if neither is pinned then the Convertor wont lock.

camaroboricua

iTrader: (23)

Thanks for the explanations, It helps to better understand what needs to happen. I wired the relay as stated on the previous post. Which seems to be the exact way you mention it. So unless I accidentally did it wrong, it didnt work for me. I hear it click but the TC still stays locked. I ran out of time so I havent messed with it since and I didnt use the multimeter to verify that it worked. Now that I understand it better I can go and test it to see if it is working properly or where I messed up.
My harness is from a 2000 A4 and the only modifications to it were the ones needed to make the swap work. I did not disturb the trans wiring.