P0847

P0847-SECONDARY OIL PRESSURE SENSOR CIRCUIT LOW





For a complete wiring diagram Refer to Diagrams/Electrical. Electrical Diagrams


Theory of Operation


The Transmission Control Module (TCM) monitors the input voltage from the secondary pulley pressure sensor. When the voltage is below a predetermined limit a DTC will set.


- When Monitored:

Ignition on, system voltage between 9.0 and 16.0 volts.


Transmission temperature greater than -20� C (-4� F)


No active DTCs from the following:

- Primary Oil Pressure Sensor High
- Sensor ground
- Set Condition:

When the monitored voltage drops below 0.09 volts for the period of 5 seconds.







Always perform the CVT Pre-Diagnostic Troubleshooting procedure before proceeding. CVT - Pre-Diagnostic Troubleshooting Procedure



Diagnostic Test


1. CHECK THE SECONDARY PRESSURE SENSOR VOLTAGE

With the scan tool, read the Secondary Pulley Pressure Sensor voltage.

Is the voltage below 0.09 volts?

Yes

- Go To 2

No

- Go To 7



2. CHECK THE (T72) 5 VOLT SUPPLY CIRCUIT





Turn the ignition off to the lock position.

Disconnect the Transmission Solenoid/Pressure Switch Assembly harness connector.

Ignition on, engine not running.

Measure the voltage of the (T72) 5 volt Supply circuit in the Transmission Solenoid/Pressure Switch Assembly harness connector.

Is the voltage 5.0 volts (±0.2 volts)?

Yes

- Go To 3

No

- Go To 6



3. CHECK THE (T50) SECONDARY PRESSURE SENSOR SIGNAL CIRCUIT





Turn the ignition off to the lock position.

Disconnect the Transmission Solenoid/Pressure Switch Assembly harness connector.

Ignition on, engine not running.

Connect a jumper wire between the (T50) Secondary Pressure Sensor Signal circuit and the (T72) 5 volt Supply circuit in the Transmission Solenoid/Pressure Switch Assembly harness connector.

With the scan tool, read the Secondary Pulley Pressure Sensor voltage.

Is the voltage 5.0 volts (±0.2 volts)?

Yes

- Replace CV Transmission or replace the Secondary Pressure Sensor (Valve Body).
- Perform CVT VERIFICATION TEST. Verification Tests

No

- Go To 4



4. CHECK THE (T50) SECONDARY PRESSURE SENSOR SIGNAL CIRCUIT FOR AN OPEN





Turn the ignition off to the lock position.

Disconnect the TCM C2 harness connector.

Measure the resistance of the (T50) Secondary Pressure Sensor Signal circuit between the TCM C2 harness connector and the Transmission Solenoid/Pressure Switch Assembly harness connector.

Is the resistance above 5.0 ohms?

Yes

- Repair the (T50) Secondary Pressure Sensor Signal circuit for an open or high resistance.
- Perform CVT VERIFICATION TEST. Verification Tests

No

- Go To 5



5. CHECK THE (T50) SECONDARY PRESSURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO GROUND





Measure the resistance between ground and the (T50) Secondary Pressure Sensor Signal circuit.

Is the resistance below 5.0 ohms?

Yes

- Repair the (T50) Secondary Pressure Sensor Signal circuit for a short to ground.
- Perform CVT VERIFICATION TEST. Verification Tests

No

- Using the schematics as a guide, check the Transmission Control Module (TCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. Check for any Service Bulletins for possible causes that may apply. If no problems are found, replace the TCM.
- Perform CVT VERIFICATION TEST. Verification Tests



6. CHECK THE (T72) 5 VOLT SUPPLY CIRCUIT FOR AN OPEN





While back probing, measure the voltage of the (T72) 5 Volt Supply circuit in Transmission Solenoid/Pressure Switch Assembly harness connector.

Is the voltage 5.0 volts (±0.2 volts)?

Yes

- Repair the (T72) 5 volt Supply circuit for an open or high resistance.
- Perform CVT VERIFICATION TEST. Verification Tests

No

- Using the schematics as a guide, check the Transmission Control Module (TCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. Check for any Service Bulletins for possible causes that may apply. If no problems are found, replace the TCM.
- Perform CVT VERIFICATION TEST. Verification Tests



7. INTERMITTENT WIRING AND CONNECTORS

The conditions necessary to set this DTC are not present at this time.

Using the schematics as a guide, inspect the wiring and connectors specific to this circuit.

Wiggle the wires while checking for shorted and open circuits.

Were there any problems found?

Yes

- Repair as necessary.
- Perform CVT VERIFICATION TEST. Verification Tests

No

- Test Complete.