P0849
Transmission Fluid Pressure Sensor/Switch B Circuit Intermittent
The transmission fluid pressure sensor/switch B reports a circuit intermittent fault. Hydraulic pressure feedback for shift control is unreliable on this channel.
- Check engine light: Yes
- Emissions related: No
- Repair difficulty: medium
Symptoms
- Check engine or transmission warning light on
- Harsh, delayed, or missing shifts
- Possible limp mode (locked in one gear)
- Slipping or shuddering during gear changes
Common causes
Ordered by how often each turns out to be the cause.
- Connector not seatedCommon
- Harness chafing intermittentlyPossible
- Connector with intermittent contact under vibrationLess likely
Parts involved
- Tfp Sensor B
- Wiring Harness
- TCM
P0849 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.