Cut & paste:
Originally Posted by LexusFTW
Your best bet is so just splice directly into the ignition harness. Neither the Supra TT or N/A harnesses work on the SC300 so unless you can find a soarer harness, just splice your existing harness. It's not that difficult.

Harness <------>Turbotimer

Black/Orange <-> Green
Pink/Blue <----> Blue
White <--------> Red
GND <----------> Black and Grey(handbrake)

The harness you splice into should have a black plug and is under the drivers side dash on the right side of the steering column.

--------------------------------------------------------------------------
Did you read the link?? It is the wiring diagram...........

What are you guys talking about car theft???

There's no figging key in the car. (steering wheel will lock) And if you wire
the parking brake trip like your supposed to it kills the engine the moment
the parking brake is released.

 

thats wrong, like i mentioned there are two ignition wires. so that wont work its as follows.

Constant 12V+ White
Ignition Black/Yellow
Ignition 2 Black/Orange
Accessory Pink/Blue

the hand break you need to run a wire to the hand break switch just one wire which is grounded when the e-brake is up.

this is how i have mine wired and it works with one ignition wire hooked up the car does not stay on.

 

good to have that info. appreciate it alot. im still gonna just save the money for an egt gauge or something. my lifestyle lets me sit in the car for a good minute or however long desired to let her cool down. it is a cool looking gadget none the less. Thanks to all who input.

 

bring this back on more time for correction! to my knowledge there is a different wiring set up for the OBDI and the OBDII, SCxxx

the ODBI uses:
Black/Orange <-> Green
Pink/Blue <----> Blue
White <--------> Red
GND <----------> Black and Grey(handbrake)

The harness you splice into should have a black plug and is under the drivers side dash on the right side of the steering column.

that why "Cleanshots" had to mod the directions!
because the OBDII:
would need the white plug and the Blue wire from the turbo timer to end up going to a thick white wire

correct me if I'm wrong