Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

(Some people have issue connecting. LEMON is investigating. For now, use Firefox or change your DNS server)

Or, hide this message: temporarily or permanently

Air Temperature Sensor ( Ambient / Intake ): Description and Operation

Intake air temperature sensor





The temperature sensor is located in the pressure pipe ahead of the throttle body.

The control module measures the temperature in the intake manifold by applying 5 V to the sensor from pin 14 via an integral 2.2 Kilo Ohm resistor. The sensor is grounded via pin 17.

The voltage across pins 14 and 17 indicates the temperature of the intake air. Together with the engine load signal from LH, this voltage is used to calculate the boost pressure.