Sensor test values
When the engine is cold, the resistance and output voltage from the Intake Air Temperature sensor should be the same as the resistance and output voltage of the Intake Air Temperature sensor (IAT) ie 35W and 3V respectively, depending on ambient temperature.
The Hall generator consists of a permanent magnet and a semiconductor chip separated by a vane driven in this case by the transmission gearing. As the vane rotates it passes the gap between the magnet and the chip, and the difference in magnetic flux causes the chip to switch on and off. A voltage is supplied to the chip and the return voltage consists of an on-off signal which will be timed to the rotation of the transmission. In this case the voltage of the signal does not vary, only the frequency.
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