DTC Troubleshooting: P0872
DTC P0872: Transmission Fluid Pressure Switch C (4th Clutch) Circuit Low
NOTE:
Before you troubleshoot, record all freeze data and any on-board snapshot with the HDS, and review the General Troubleshooting Information.
This code is caused by an electrical circuit problem and cannot be caused by a mechanical problem in the transmission.
If DTC P0872 is stored in the PCM, the transmission does not shift to any gear other than 1st or 4th gear because of the fail-safe function.

DTC Description
Confirmed DTC
Pending DTC
Freeze Frame
P0872 Transmission Fluid Pressure Switch C (4th Clutch) Circuit Low
      

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
4th 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 transmission fluid pressure switch C (4th clutch) and the PCM.?
2.
Determine possible failure area (transmission fluid pressure switch C (4th clutch), others):

Determine possible failure area (transmission fluid pressure switch C (4th clutch), 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
4th Pressure Switch
OFF
      

Do the current condition(s) match the threshold?

     
YES
     
     
     
     
NO
     
     
     
Go to step 3.
3.
Shorted wire check (OP4SW line):

Shorted wire check (OP4SW 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
 
Transmission fluid pressure switch C (4th clutch) 1P connector: disconnected
 
PCM connector B (51P): disconnected
Test circuit
OP4SW
Test point 1
PCM connector B (51P) No. 26 (BLU)
Test point 2
Body ground


Is there continuity?

     
YES
     
     
     
Repair a short to body ground in the OP4SW wire between transmission fluid pressure switch C (4th clutch) and the PCM.?
     
NO
     
     
     
The OP4SW wire is OK. Replace the PCM.?