Blitz Exhaust Temp gauge wiring

[1200det]

Ive had this old Blitz Exhaust Temp gauge laying around for years , I only have the gauge and the wiring as pictured.

Any idea what Temp Sender i need ?
Wiring ?

Plug 1 = Red , White

Plug 2 = Black , Yellow , Red





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[Toobs]

You'll most likely find you need a K type thermocouple (very common)

I'd say the 2P plug is for the thermocouple (doesn't matter which way it's wired if it's a K type as they are basically a temp variable resistor)

The 3P plug would be your power.
Normally:
Yellow = Constant Power (i.e. direct to battery)
Red = Switched Power (i.e. ignition)
Black = Ground
In this case I'd suggest that yellow is probably illumination as there is no real reason for a temp gauge to need constant power.

Just go to your cars battery and put the black wire to -ve and then touch the other two to the +ve terminal one at a time to see which is which.

If your worried about blowing the gauge I'd suggest putting a potentiometer in line with the earth wire and starting at max resistance adjust the resistance down slowly until you see the backlight glow faintly.
Alternatively chuck an ohm meter (multimeter set to resistance) across the yellow and black and then the red and black... reason is a light bulb will have a fairly low resistance (~1ohm for 10W) but the circuitry for the actual gauge will be quite high in resistance.
The lower resistance is your light.

If the gauge is working and does require a K type thermocouple it should flick all the way to max temp if you touch the two probe wires together (i.e. almost zero resistance)
With the probe wires not connected to anything it will show the minimum temp.
In doing this I would just really quickly brush the probe wires past each other and you should see the needle jump... I wouldn't hold the wires together for too long as the gauge probably isn't designed to see a short on the probe wires.

[oldcorollas]

eh? no no, thermocouples create voltage, and there is a + and - howver... to test, just grab with fingers.. if temp goes down.. it's wired backwards

http://www.picotech.com/applications/thermocouple.html

[1200det]

Cheers gentlemen , Now i guess i better start Ebaying for a Sensor.


.

[Toobs]

eh? no no, thermocouples create voltage, and there is a + and - howver... to test, just grab with fingers.. if temp goes down.. it's wired backwards

http://www.picotech.com/applications/thermocouple.html

You are correct... my bad, I was thinking of LDR's.