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Input Signals

WARNING: This page is about a different car, the 2003 Lexus RX 300 and 2002 Lexus RX 300. However, it is still accessible from the selected car via links, so may be relevant.
  1. Engine Coolant Temperature Signal Circuit -  The engine coolant temperature sensor detects the engine coolant temperature and has a built-in thermistor with a resistance, which varies according to the engine coolant temperature. The engine coolant temperature which is input into terminal No. E8-14 (THW) of the engine control module as a control signal.
  2. Intake Air Temperature Signal Circuit -  The intake air temperature sensor is installed in the mass air flow meter and detects the intake air temperature which is input as a control signal to terminal No. E8-22 (THA) of the engine control module.
  3. Vehicle Speed Signal Circuit -  The vehicle speed signal is input from the ABS speed sensor to ABS & BA & TRAC & VSC ECU, and are sent to the engine control module through communication control.
  4. RPM Signal Circuit -  Camshaft position is detected by the VVT sensors and it's signal is input to terminals No. E9-10 (VV1+) and E9-22 (VV2+) of the engine control module as a control signal. Also, engine RPM is detected by the crankshaft position sensor and is input as a control signal to terminal No. E8-16 (NE+).
  5. Throttle Position Signal Circuit -  The throttle position sensor detects the throttle valve opening angle as a control signal, which is input into terminal No. E8-23 (VTA1) of the engine control module.
  6. Battery Signal Circuit -  Voltage is constantly applied to terminal No. E5-1 (BATT) of the engine control module. With the ignition switch turned on, the voltage for engine control module start-up power supply is applied to terminal No. E5-16 (+B) of the engine control module via the EFI relay. The current flowing through the IGN fuse flows to terminal No. E5-2 (IGSW) of the engine control module.
  7. Intake Air Volume Signal Circuit -  Intake air volume is detected by the mass air flow meter and the signal is input to terminal No. E8-10 (VG) of the engine control module as a control signal.
  8. Stop Light Switch Signal Circuit -  The stop light switch is used to detect whether the vehicle is braking or not and the signal is input into terminal No. E5-15 (STP) of the engine control module as a control signal.
  9. Starter Signal Circuit -  To confirm whether the engine is cranking, voltage is applied to the started motor. If cranking is detected, the signal is input into terminal No. E5-7 (STA) of the engine control module as a control signal.
  10. Engine Knock Signal Circuit -  Engine knocking is detected by knock sensors and the signal is input into terminals No. E9-28 (KNKL) and E9-27 (KNKR) as a control signal.
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