P0756

DTC P0756 Shift Solenoid B Performance (Stuck Off)





Circuit Description
The shift solenoid B is used to control fluid flow acting on the 2-3 shift valves. The solenoid is a normally open exhaust valve that is used with the shift solenoid (A) to allow four different shift combinations.
This DTC detects when there is only a 4-3-3-4 shift pattern depending on the state of the mechanical failure instead of a 1-2-3-4 shift pattern. This is a type "B" DTC.

Conditions For Setting The DTC
- No ETC DTCs.
- No OSS DTCs P0722 or P0723.
- No TCC solenoid DTC P0742, P1860, P1870.
- No shift solenoid DTCs P0753, P0758.
- Output speed is greater than 375 rpm.
- Gear range is D4.
- Transmission fluid temperature is between 20° and 130°C (68° and 266°F).
- No range code P0705, P0706.
- No torque code (to be confirmed).
- Engine run for more 0 seconds and influed cut-off (to be confirmed).
All of the above conditions have been met and the combination 1, 2 occur two consecutive times:

Condition 1:
- 1st gear is commanded for > 1 second.
- 40 < Engine Torque < 400 Nm
- Throttle position > 10%
- -2300 < TCC Slip < 200 rpm
- Transmission output speed > 400 rpm
- Speed ratio > 0.3
- 0.60 < Modeled Ratio < 1.49 for 1 second.

Condition 2:
- 2nd gear is commanded for 1 > second.
- 40 < Engine Torque < 400 Nm
- Throttle position > 10%
- -8000 < TCC Slip < 8000 rpm
- Speed ratio > 0.6
- 0.92 < Modeled Ratio < 1.5 for 0.687 second.

Action Taken When the DTC Sets
- Maximum line pressure.
- For lamp illuminate refer to DTC type definition (type B).
- Turn Force Motor OFF.

Conditions For Clearing The MIL/DTC
- The PCM will turn off the MIL and CHECK TRANS Lamp after three consecutive ignition cycles without a failure reported.
- The DTC can be cleared from the PCM history by using a scan tool.
- The DTC will be cleared from history when the vehicle has achieved 40 warmup cycles without a failure reported.
- The PCM will cancel the DTC default actions when the fault no longer exists and the ignition is cycled "off" long enough to power down the PCM.

Diagnostic Aids
- Verify that the transmission meets the specifications in the 4L30-E shift speed chart.
- Other internal transmission failures may allow more than one shift to occur.

Test Description
The numbers below refer to the step numbers on the diagnostic chart:
2. This test checks the function of the range switch (mode switch).
3. This test checks for selected gear ratio vs. a ratio not obtainable under normal driving conditions.

DTC P0756 Shift Solenoid B Performance (Stuck Off)





Step 1





Step 2 - 3





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