DTC Advanced Diagnostics: P0842
DTC P0842:Transmission Fluid Pressure Sensor/Switch A Circuit Low

General Description

The CVT driven pulley pressure sensor uses a strain gauge. The output voltage changes depending on the driven pulley pressure. The powertrain control module (PCM) sends a 5 V reference voltage to the sensor through a pull-up resistor. When the driven pulley pressure is low, the sensor resistance decreases and the PCM detects a low signal voltage. Conversely, when the driven pulley pressure is high, the sensor resistance increases and the PCM detects a high signal voltage. If the CVT driven pulley pressure sensor signal voltage is a specified voltage for a set time, the PCM detects a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type
Execution
Continuous
Sequence
None
Duration
10 seconds or more
DTC Type
Two drive cycles, MIL off, Shift position indicator blinks

Enable Conditions
Condition
 
State of the engine
Running

Malfunction Threshold
The CVT driven pulley pressure sensor output voltage [Driven Pulley Pressure Sensor (V)] is less than 0.21 V for at least 10 seconds.

[ ]: HDS Parameter

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.
CVT driven pulley pressure sensor PDN line short to ground
CVT driven pulley pressure sensor failure
PCM internal circuit failure

Confirmation Procedure
Operating Condition
1.
Start the engine.
2.
Shift to P position/mode, and wait for at least 10 seconds.
3.
Turn the vehicle to the OFF (LOCK) mode.
4.
Repeat Driving Pattern steps 1 through 2.
With the HDS
None.

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, the shift position indicator blinks and a Confirmed DTC and the freeze data are stored. The MIL does not come on.

Conditions for clearing the DTC
The shift position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the 12 volt battery.