AT2–72 A340E (2JZ—GTE) AUTOMATIC TRANSMISSION – TROUBLESHOOTING DTC 42 No.1 Vehicle Speed Sensor Signal Circuit CIRCUIT DESCRIPTION The No. 1 vehicle speed sensor outputs a 4–pulse signal for every revolution of the rotor shaft, which is rotated by the transmission output shaft via the driven gear. After this signal is converted into a more precise rectangular waveform by the waveform shaping circuit inside the combination meter, it is then transmitted to the engine control module. The ECM determines the vehicle speed based on the fre- quency of these pulse signals. Transmission Output Shaft A/T 4-pulse 4-pulse ECM Rotor Shaft No.1 Vehicle Speed Sensor Telltale Light RH Driven Gear No.1 Vehicle Speed Sensor FI6643 Q04361 DTC No. Diagnostic Trouble Code Detection Condition Trouble Area 42 All conditions below are detected for 4 secs. or more. (2 trips detection logic)* (a) No No.1 vehicle speed sensor signal in 16 pulses of No.2 vehicle speed sensor signal. (b) Vehicle speed: 9 km/h (5.6 mph) or more (c) Park/neutral position switch: OFF (Other than P or N position) No. 1 vehicle Speed sensor Telltale light RH Harness or connector between No. 1 vehicle speed sensor and ECM ECM * See page AT2–58 HINT: In test mode, diagnostic trouble code 42 is output when vehicle speed is 5 km/h (3 mph) or below. <Reference> Waveform between terminals SP1 and E2 when vehicle speed is approx. 20 km/h (12 mph). HINT: As the vehicle's speed increases, the signal output from SP1 increases. 2 V/div 20 msec./division V01495