DTC Troubleshooting: P0843
DTC P0843: Transmission Fluid Pressure Sensor/Switch "A" Circuit High
NOTE:
Before you troubleshoot, 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.

DTC Description
Confirmed DTC
Pending DTC
Freeze Frame
P0843 Transmission Fluid Pressure Sensor/Switch "A" Circuit High
      

1.
Problem verification:

Problem verification
?1.
Turn the vehicle to 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
Driven Pulley Pressure Sensor(V)
More than 4.84
V
    

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 CVT driven pulley pressure sensor and the PCM. If the freeze data/on-board snapshot of this DTC is recorded, try to reproduce the failure under the same conditions with the freeze data/on-board snapshot.?
2.
Determine possible failure area (CVT driven pulley pressure sensor, others):

Determine possible failure area (CVT driven pulley pressure sensor, others)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Disconnect the following connector.
CVT driven pulley pressure sensor 3P connector

?3.
Connect terminals A and B with a jumper wire.
Terminal A
CVT driven pulley pressure sensor 3P connector No. 1
Terminal B
CVT driven pulley pressure sensor 3P connector No. 2


?4.
Turn the vehicle to the ON mode.

?5.
Check the parameter(s) below with the HDS.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
Driven Pulley Pressure Sensor(V)
More than 4.84
V
    

Do the current condition(s) match the threshold?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
3.
Open wire check (PDN line):

Open wire check (PDN line)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Remove the jumper wire.

?3.
Jump the SCS line with the HDS.


?4.
Disconnect the following connector.
PCM connector C (51P)

?5.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
CVT driven pulley pressure sensor 3P connector: disconnected
 
PCM connector C (51P): disconnected
Test point 1
CVT driven pulley pressure sensor 3P connector No. 2
Test point 2
PCM connector C (51P) No. 49


Is there continuity?

     
YES
     
     
     
The PDN wire is OK. Go to step 4.
     
NO
     
     
     
Repair an open in the PDN wire between the CVT driven pulley pressure sensor and the PCM.?
4.
Open wire check (SG2 line):

Open wire check (SG2 line)
?1.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
CVT driven pulley pressure sensor 3P connector: disconnected
 
PCM connector C (51P): disconnected
Test point 1
CVT driven pulley pressure sensor 3P connector No. 1
Test point 2
PCM connector C (51P) No. 31


Is there continuity?

     
YES
     
     
     
The SG2 wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If DTC P0843 goes away and the PCM was updated, troubleshooting is complete. If DTC P0843 goes away and the PCM was substituted, replace the original PCM.?
     
NO
     
     
     
Repair an open in the SG2 wire between the CVT driven pulley pressure sensor and the PCM.?