Conditions for Setting the DTC

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C0055

Any of the following occurrences may cause the DTC to set.

The EBCM detects an open or shorted vehicle speed signal circuit for 500 milliseconds.
The EBCM detects the absence of the vehicle speed signal for 5 seconds. If more than one absent wheel speed sensor signal is detected, the condition must be present for 120 seconds to set DTCs.
The EBCM detects an erratic vehicle speed signal for 200 milliseconds.
P0609

The PCM detects low voltage on the vehicle speed signal circuit for 45 seconds.