DTC Troubleshooting: P0842
DTC P0842: Transmission Fluid Pressure Sensor/Switch "A" Circuit Low
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
P0842 Transmission Fluid Pressure Sensor/Switch "A" Circuit Low
      

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)
Less than 0.21
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 (PDN line, others):

Determine possible failure area (PDN line, others)
?1.
Turn the vehicle to the OFF (LOCK) mode.

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

?3.
Turn the vehicle to the ON mode.

?4.
Check the parameter(s) below with the HDS.
Signal
Threshold
Current conditions
Values
Unit
Values
Unit
Driven Pulley Pressure Sensor(V)
Less than 0.21
V
    

Do the current condition(s) match the threshold?

     
YES
     
     
     
Go to step 3.
     
NO
     
     
     
Go to step 4.
3.
Shorted wire check (PDN line):

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

?2.
Jump the SCS line with the HDS.


?3.
Disconnect the following connector.
PCM connector C (51P)

?4.
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
Body ground


Is there continuity?

     
YES
     
     
     
Repair a short to ground in the PDN wire between the CVT driven pulley pressure sensor and the PCM.?
     
NO
     
     
     
The PDN wire is OK. Update the PCM if it does not have the latest software, or substitute a known-good PCM, then recheck. If DTC P0842 goes away and the PCM was updated, troubleshooting is complete. If DTC P0842 goes away and the PCM was substituted, replace the original PCM.?
4.
Open wire check (VCC2 line):

Open wire check (VCC2 line)
?1.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
 
CVT driven pulley pressure sensor 3P connector: disconnected
Test point 1
CVT driven pulley pressure sensor 3P connector No. 3
Test point 2
Body ground


Is there about 5 V?

     
YES
     
     
     
     
NO
     
     
     
Repair an open in the VCC2 wire between the CVT driven pulley pressure sensor and the PCM.?