P0845: Transmission Fluid Pressure Sensor/Switch “B” Circuit OBD-II Trouble Code

The transmission fluid pressure sensor delays the amount of hydraulic pressure in the transmission to the ECU, so it can know when and how to shift. If there is a problem with this sensor, a P0845 DTC will be saved.

Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.

What Transmission Do I Have?

How Serious is the Code?

A P0845 diagnostic trouble code is serious, because the underlying transmission problems can impact the drivability of your vehicle. These include harsh shifts, failed gear engagement and torque converter problems.

Symptoms

Symptoms of a P0845 include:

  • Erratic or hard shifts
  • Failure to shift
  • Decreased fuel economy
  • Torque converter clutch failure
  • Transmission overheating

Causes

  • Not enough transmission fluid
  • Dirty transmission fluid / filter
  • Transmission fluid leak
  • Damaged wiring/connector
  • Bad transmission fluid pressure sensor
  • Malfunctioning transmission pump
  • Failing torque convertor
  • Bad pressure control solenoid
  • Bad pressure regulator
  • Problems with fluid pressure
  • Valve body issue
  • TCM failure

How to Diagnose the Code?

When diagnosing a P0845 OBDII trouble code, it’s important to note the level and condition of transmission fluid. Any dirt or debris in the transmission fluid can affect both the hydraulic pressure and the performance of this sensor. Damaged wiring and connectors can also cause a problem, as can transmission fluid leaks. If nothing has been found up to this point, then further mechanical diagnoses may be needed.

Need a replacement transmission? Get an estimate for replacement transmissions and local installation. Look up your transmission model by vehicle make and model.

What Transmission Do I Have?

What Repairs Will Fix P0845?

  • Change transmission fluid and filter
  • Repair leaks
  • Repair or replace damaged wiring and connectors
  • Replace transmission fluid pressure sensor
  • Repair or replace torque converter
  • Repair or replace valve body
  • Replace transmission pump
  • Replace pressure control solenoid
  • Replace pressure regulator
  • Reprogram or replace TCM

Related Codes

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