Advanced Diagnostics
Advanced Diagnostics-DTC P0848: Transmission Fluid Pressure Switch B (3rd Clutch) Circuit HighGeneral 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 OFF while driving the vehicle with the rotation speed ratio of the input/output pulses is that of 3rd gear, 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) [3RD PRESSURE SWITCH] to the PCM is high when driving in 3rd gear.
Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- Transmission fluid pressure switch B (3rd clutch) OP 3 SW line short to power
- Transmission fluid pressure switch B (3rd clutch) OP 3 SW line open (includes connector loose connection or disconnection)
- Transmission fluid pressure switch B (3rd clutch) stuck off
- PCM internal circuit failure
Confirmation Procedure
With the HDS
None.
With the Driving Pattern
1. Start the engine.
2. Drive the vehicle in 3rd 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 during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, a Confirmed DTC and the freeze data are stored. The MIL does not come on.
Conditions for clearing the DTC
The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.