P0841 Volvo LR Pressure Switch Rationality Fault

Possible causes

– Transmission Solenoid/Pressure Switch harness is open or shorted
– Transmission Solenoid/Pressure Switch circuit poor electrical connection
– Faulty Transmission Solenoid/Pressure Switch
– 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.

P0841 Volvo Description

Low/Reverse (LR).

The Transmission Control Module (TCM) has detected a pressure switch open or closed at an incorrect time.