Advanced Diagnostics

Advanced Diagnostics - DTC P0847: Short in Transmission Fluid Pressure Switch B (3rd Clutch) Circuit, or Transmission Fluid Pressure Switch B (3rd Clutch) Stuck ON










General Description
Transmission fluid pressure switch B (3rd clutch) is installed in the hydraulic pressure circuit to the 3rd clutch. When hydraulic pressure is supplied to the 3rd clutch, the switch is turned ON. When hydraulic pressure is not supplied to the 3rd clutch, the switch is turned OFF. The signal from transmission fluid pressure switch B (3rd clutch) is input to the powertrain control module (PCM). The PCM detects the hydraulic pressure supply conditions at the gear change to 3rd gear (2nd --> 3rd, 4th --> 3rd) to reduce the shock that occurs at the gear change. If transmission fluid pressure switch B (3rd clutch) is ON while driving the vehicle with the rotation speed ratio of the input/output pulses is other than the 3rd ratio, the PCM detects a transmission fluid pressure switch B (3rd clutch) failure and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status






Enable Conditions






Malfunction Threshold
The input signal from transmission fluid pressure switch B (3rd clutch) to the PCM is low when driving in 1st gear, 2nd gear, 4th gear, or 5th gear.

Driving Pattern
1. Start the engine.
2. Drive the vehicle in 4th gear for at least 2 seconds.

- Drive the vehicle in this manner only if the traffic regulations and ambient conditions allow.

Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected, the MIL comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the PCM memory.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.