P0991
Transmission Fluid Pressure Sensor/Switch E Circuit Intermittent
Generic code
Transmission System
High severity
Hard repair
Free on OBD DashX
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What P0991 means
- The fault code P0991 indicates an intermittent issue in the circuit of the transmission fluid pressure sensor/switch 'E'. This sensor/switch is responsible for monitoring the fluid pressure within the transmission. An intermittent circuit issue suggests that there are sporadic disruptions in the electrical signal or connection.
Possible symptoms
- Intermittent illumination of the Malfunction Indicator Lamp (MIL) or Check Engine Light.
- Occasional abnormal transmission shifting behavior.
- Intermittent harsh or delayed shifting between gears.
- Erratic or unpredictable gear changes at times.
- Momentary reduction in performance or power from the transmission.
- Other associated transmission
- related fault codes may be present intermittently.
- No consistent or noticeable drivability issues are typically associated with this fault code.
Possible causes
- Intermittent wiring or electrical connection issues in the circuit
- Loose or corroded connectors or terminals
- Faulty transmission fluid pressure sensor/switch 'E'
- Vibrations or physical damage affecting the circuit
- Intermittent fault in the transmission control module (TCM)
Related parts
- Hydraulic Pressure Sensor: Hydraulic oil is needed for the gear lubrication system. This sensor measures oil pressure. This car's sensor has a problem which may cause difficulty in shifting gears
Possible solutions
- Inspect the wiring and electrical connections in the circuit for any signs of damage, looseness, or corrosion. Ensure all connectors and terminals are securely connected.
- Repair or replace any damaged or faulty wiring, connectors, or terminals as necessary.
- Test and replace the transmission fluid pressure sensor/switch 'E' if it is determined to be faulty.
- Address any vibrations or physical damage that may be affecting the circuit.
- Perform diagnostic tests on the transmission control module (TCM) to identify any intermittent faults and repair or replace as necessary.
Free on OBD DashX
P0991 on OBD DashX
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