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description
The speed sensor detects the wheel speed and sends the appropriate signals to the skid control ecu.
The skid control ecu converts these wheel speed signals into a 4-pulse signal and outputs it to the ecm via the combination meter. The ecm determines the vehicle speed based on the frequency of these pulse signals.


Monitor description
The ecm assumes that the vehicle is being driven, when the indicated engine speed is more than 2,300 rpm and 30 seconds have elapsed since the park/neutral position (pnp) switch was turned off. If there is no speed signal from the combination meter, despite these conditions being met, the ecm interprets this as a malfunction in the speed signal circuit. The ecm then illuminates the mil and sets the dtc.
Monitor strategy

Typical enabling conditions
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Typical malfunction thresholds
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Wiring diagram

Inspection procedure
Hint:
Read freeze frame data using the intelligent tester. Freeze frame data records the engine condition when malfunctions are detected. When troubleshooting, freeze frame data can help determine if the vehicle was moving or stationary, if the engine was warmed up or not, if the air-fuel ratio was lean or rich, and other data from the time the malfunction occurred.
Hint:

Ok: vehicle speeds displayed on tester and speedometer display are equal.

Standard voltage 

Standard voltage 
Hint:
The output voltage should fluctuate up and down, similarly to the diagram, when the wheel is turned slowly.

Standard resistance (check for open)

Standard resistance (check for short)



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