DTC 42

DTC 42 No.1 Vehicle Speed Sensor Signal Circuit

Signal Flow:

Component Location:

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 odometer and trip meter, it is then transmitted to the engine control module. The ECM determines the vehicle speed based on the frequency of these pulse signals.





DETECTING CONDITION

HINT: In test mode, diagnostic trouble code 42 is output when vehicle speed is 5 km/h (3 mph) or below.

Reference Waveform:

- Waveform between terminals SP1 and El when vehicle speed is approx. 20km/h (12mph).

HINT: As the vehicle speed increases, the number of signals from SP1 increases.





WIRING DIAGRAM

Step 1:

Step 2:

Step 3:

INSPECTION PROCEDURE