DTC P0642:00 [MZI-3.7]: Notes

WARNING: This page is about a different car, the 2009 Mazda 6. However, it is still accessible from the selected car via links, so may be relevant.

DETECTION CONDITION & POSSIBLE CAUSE

DTC P0642:00	Sensor reference voltage circuit low
DETECTION CONDITION	Indicates the reference voltage circuit is lower than reference voltage minimum.
POSSIBLE CAUSE	Short to ground between fuel tank pressure sensor terminal C and PCM terminal 1D Connector or terminal malfunction Fuel tank pressure sensor malfunction
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