TRDSupraSE

My temp guage doesn't read normally after the TT swap, now is there some kind of resistor to wire in that I'm not aware of?

Thanks...

zegnaguy

iTrader: (1)

What location and color of wire did you hook it up to?

ManicSC

330ohm behind the gauge, not at the sensor

SC300TT!

I didn't have any temp problems with my swap.
There are two temp probes in the engine: One for the gauge and one for the
EFI computer. The coolant temp has the smaller single wire connector.
Is it possible that they got mixed up?

zegnaguy

iTrader: (1)

I should have explained better. I'm looking for the wire that hooks up to the dash temp gauge. Do know what color and location I can tap my standalone too?

philauldridge

It IS common to have discrepancies with coolant temperature with the Supra swap. My guess is that your temp gage goes right to the top of the scale soon after warmup?

I have found through experimentation that a 330 ohm resistor, wired inline in the temp sender wire, brings the temp voltage to the proper level so that normal operation shows mid-scale. You can either wire in the resistor under the hood near the temp sensor at the front of the engine, or find the same wire where it goes into the ECU under passenger floorboard. This would be the Blue/Yellow wire which is connected between the old Supra connector II1pin 19 (I'm assuming you are using the Supra ECU?) and the Lexus connector IK1 pin 9.

Other swappers have reported to me using slightly different resistance values. Just go to Radio Shack and buy a handful of resistors with values between, say 75 ohm and 500 ohm, and then just experiment until you get a reasonable gage reading.