HELP Brake switch wiring- 4L80E TCC

[Tony1968]

87a is usually not used. Wire nut or tape it off
It is a normally closed terminal

 

[GroceryGetter83]

87a is usually not used. Wire nut or tape it off
It is a normally closed terminal

thats what I did! 😅

 

[GroceryGetter83]

Well I think it’s done right. Will report back in the morning.

Light on the switch (3 post) only comes on when I press the brake pedal (and switch is on). I might have to Switch the input to +12v as the trigger but we will see!

Thank you for the help!

 

[64nailhead]

Sounds like you have it right it correct and you added a light to the switch circuit, correct? So the light illuminates when you have the brake pedal pushed and the dash switch on? If yes and yes, then you’re all set except the last thing that needs to be done in the ecm.

You need to assign the input and hook into that. Then need to move that input in the pin map. I have to admit I had a tough time with this coming from the Megasquirt world. Make sure you assign the input as ‘G’ indicating ground switched.

Then play from there. Let me know if you get snagged.

 

[GroceryGetter83]

Off:


Armed:


On:

 

[GroceryGetter83]

Two step doesn’t work how I have the input set/wired. It’s set as ground in the Holley but I need to try it as +12v.

If that doesn’t work, then I Need to reinvestigate the wiring.

 

[fleming442]

That should fix it. Most aftermarket illuminated switches need 12, not ground. So if your light works, your computer doesn't like it.

 

[Tony1968]

If you are talking about terminator then yes Holley uses the ground as a switch.

 

[Tony1968]

That should fix it. Most aftermarket illuminated switches need 12, not ground. So if your light works, your computer doesn't like it.

An illuminated switch will require a ground
I'm sure you know that and just miss typed it

 

[GroceryGetter83]

These are the switches:
2PCS Electrical Large 30A 12 Volt Heavy Duty Toggle Switch Lighted Racking Car Truck Red LED

https://www.amazon.com/dp/B07SGQ7RKP/?tag=gbody-20

I have a ground to the ground and the relay going thru the power/load on the switch.