DTC Troubleshooting: P084C
DTC P084C: Line Pressure Pressure Switch Stuck ON
NOTE:
Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review the General Troubleshooting Information.
If DTC P084C is stored in the PCM, engine torque is limited because of the fail-safe function.

DTC Description
Confirmed DTC
Pending DTC
Freeze Frame
P084C Line Pressure Pressure Switch Stuck ON
      

1.
Problem verification:

Problem verification
?1.
Press the engine start/stop button to select the ON mode.

?2.
Clear the DTC with the HDS.


?3.
Check the parameter(s) below with the HDS.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
Line Pressure Pressure Switch
ON
      

Do the current condition(s) match the threshold?

     
YES
     
     
     
The failure is duplicated. Go to step 2.
     
NO
     
     
     
Intermittent failure, the system is OK at this time. Check for poor connections and loose terminals between the line pressure switch and the PCM.?
2.
Determine possible failure area (line pressure switch, others):

Determine possible failure area (line pressure switch, others)
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Disconnect the following connector.

?3.
Press the engine start/stop button to select the ON mode.

?4.
Check the parameter(s) below with the HDS.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
Line Pressure Pressure Switch
OFF
      

Do the current condition(s) match the threshold?

     
YES
     
     
     
     
NO
     
     
     
Go to step 3.
3.
Shorted wire check (OPPLSW line):

Shorted wire check (OPPLSW line)
?1.
Press the engine start/stop button to select the OFF mode.

?2.
Jump the SCS line with the HDS.


?3.
Disconnect the following connector.

?4.
Check for continuity between test points 1 and 2.
Test condition
OFF mode
 
Line pressure switch 1P connector: disconnected
 
PCM connector B (51P): disconnected
Test circuit
OPPLSW
Test point 1
PCM connector B (51P) No. 37 (BRN)
Test point 2
Body ground


Is there continuity?

     
YES
     
     
     
Repair a short to body ground in the OPPLSW wire between the line pressure switch and the PCM.?
     
NO
     
     
     
The OPPLSW wire is OK. Replace the PCM.?