P0845 Buick Transmission Fluid Pressure Sensor B

P0846 Buick 2-4 or 2C Pressure Switch Rationality

Possible causes
– Faulty Pressure Switch Rationality
– Pressure Switch Rationality harness is open or shorted
– Pressure Switch Rationality circuit poor electrical connection
– Internal transmission damage
– Faulty Engine Control Module (ECM)
– Faulty Transmission Control Module (TCM)
Symptoms
– Engine Light ON (or Service Engine Soon Warning Light)
– Transmission will not shift gears.
P0846 Buick Description

The Transmission Control Module (TCM) has detected a fault in the pressure switch assembly

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