P0840
Transmission Fluid Pressure Sensor/Switch A Circuit
Generic code
Transmission System
High severity
Hard repair
Free on OBD DashX
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What P0840 means
- The fault code P0840 indicates that there could be an issue with the circuit that controls the transmission fluid pressure sensor or switch A. This may cause the transmission to shift poorly or not shift at all.
Possible symptoms
- Transmission shifting poorly or not at all
- Illuminated check engine light
- Harsh shifting or slipping transmission
- Reduced fuel economy.
Possible causes
- Faulty or failed transmission fluid pressure sensor or switch A
- Damaged wiring or connections in the circuit
- Loose or corroded electrical connections
- Failed transmission control module (TCM)
Related parts
- Transmission Fluid Pressure Sensor: Gear fluid line delivers gear fluid/oil between the various gear parts that need lubrication. The Gear fluid line pressure Sensor monitors the fluid pressure in the line. Problems lead to difficulty in shifting gears
Possible solutions
- Replace the transmission fluid pressure sensor or switch A
- Check and repair any damaged wiring or connections
- Tighten or clean any loose or corroded electrical connections
- Replace the transmission control module (TCM) if necessary
Free on OBD DashX
P0840 on OBD DashX
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