DTC P0643: Notes

DTC P0643 (MZI-3.5) DETECTION CONDITION AND POSSIBLE CAUSES

DTC P0643	Sensor reference voltage circuit high
DETECTION CONDITION	Indicates the reference voltage circuit is higher than reference voltage maximum.
POSSIBLE CAUSE	Short to ground between fuel tank pressure sensor terminal C and PCM terminal 1 U Fuel tank pressure sensor malfunction Connector or terminal malfunction
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