07GTS
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- VEGTS BUILT BLOWN E85
they should pull down to zero, could be 5v to 0 or even 12v to 0, they are looking for a pulse so it needs to be at zero or extremely close, they work two ways the sensor is zero then pulses out 5 or 12v, or there is already on the signal wire 5 or 12v and the sensor pulls it down to zero,I don't think it's 5v disconnected. I believe the sensors has a resistor that pulls the 12 volt down to 5....
I'm going to run with Haltech's advice that it takes 12 volt in. It's going to be a massive job if it's wrong, because my 12 volt is in the engine bay and my 5 volt supply is from the ECU and they need to be shielded wires.
easy way to test is plug sensor in or just wire it up off the vehicle and then put metal to the front of it with multimeter on the signal wire (dc volts) and earth and it should pull to zero with the metal in front and then remove metal and it will go back to the reference voltage 5 or 12v