P0844moderate severityPowertrain
Transmission Fluid Pressure Sensor/Switch A Circuit Intermittent
on 1998 Toyota Tacoma 2.7L I4 · RWD
What this code means
The PCM detected an intermittent fault in the transmission pressure sensor A circuit. The signal drops out or fluctuates unexpectedly.
Symptoms
- Intermittent harsh shifts
- Warning light comes and goes
- Occasional slipping
Common causes
- Loose or corroded connector
- Intermittent wiring fault
- Failing pressure sensor
- Vibration-related contact loss
Diagnostic steps
- Scan for stored and pending codes
- Wiggle-test wiring and connectors
- Monitor sensor data during driving
- Inspect for chafed or loose wiring
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Other Powertrain codes on this vehicle
P0001
Fuel Volume Regulator Control Circuit/Open
P0001
Fuel Volume Regulator Control Circuit/Open
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0002
Fuel Volume Regulator Control Circuit Range/Performance
P0003
Fuel Volume Regulator Control Circuit Low
P0003
Fuel Volume Regulator Control Circuit Low
P0004
Fuel Volume Regulator Control Circuit High
P0004
Fuel Volume Regulator Control Circuit High
P0005
Fuel Shutoff Valve A Control Circuit/Open
P0005
Fuel Shutoff Valve A Control Circuit/Open