P0756

DTC P0756





Circuit Description
The 2-3 shift solenoid (SS) valve is a normally-open exhaust valve that, in conjunction with the 1-2 SS valve, allows four different shifting combinations. The 2-3 SS valve is attached to the control valve body within the transmission.
The powertrain control module (PCM) monitors the actual gear ratio, and compares the actual gear ratio with the commanded gear ratio. DTC P0756 sets under two conditions:
^ A stuck ON 2-3 SS valve
^ A stuck ON 2-3 shift valve
When the PCM detects a 4-3-3-4 shift pattern, then DTC P0756 sets. DTC P0756 is a type A DTC.

DTC Descriptor
This diagnostic procedure supports this DTC:
DTC P0756 2-3 Shift Solenoid (SS) Valve Performance - No First or Second Gear

Conditions for Running the DTC
^ No MAP DTCs P0107 or P0108.
^ No TP DTCs P0122 or P0123.
^ No VSS DTCs P0502 or P0503.
^ No ISS DTCs P0716 or P0717.
^ No TCC stuck ON DTC P0742.
^ No shift solenoid electrical DTCs P0753 or P0758.
^ No TCC electrical DTC P2761.
^ The transmission fluid temperature is 20 - 130°C (68 - 233°F).
^ The TP angle is greater than 8 percent.
^ The input speed is 150 - 6,000 RPM.
^ The engine torque is greater than 27 Nm (20 ft. lbs.).
^ The TCC slip speed is greater than 200 RPM when 1st gear is commanded.
^ The time since the last gear change is 0.30 seconds.

Conditions for Setting the DTC
^ The PCM commands 1st gear with the output speed greater than 160 RPM and the gear ratio is 0.61:1-0.71:1, 4th gear, for 2.5 seconds.
^ The PCM commands 2nd gear with the output speed greater than 150 RPM and the gear ratio is 0.91:1-1.07:1, 3rd gear, for 1 second.

Action Taken When the DTC Sets
^ The PCM illuminates the malfunction indicator lamp (MIL).
^ The PCM commands an immediate landing to 2nd gear.
^ The PCM commands maximum line pressure.
^ The PCM freezes transmission adaptive functions.
^ The PCM records the operating conditions when the Conditions for Setting the DTC are met. The PCM stores this information as Freeze Frame and Failure Records.
^ The PCM stores DTC P0756 in PCM history.

Conditions for Clearing the MIL/DTC
^ The PCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
^ A scan tool can clear the MIL/DTC.
^ The PCM clears the DTC from PCM history if the vehicle completes 40 warm-up cycles without an emission-related diagnostic fault occurring.
^ The PCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the PCM.

Diagnostic Aids
^ If you clear DTC P0756, and then cannot set DTC P0756 again, inspect for:
^ Fluid contamination
^ Plugged fluid circuits
^ Restricted fluid circuits

Test Description





These numbers refer to the step numbers on the diagnostic table.
3. This step verifies a 4-3-3-4 shift pattern.
4. This step tests for a mechanical or hydraulic condition causing the 2-3 SS valve to be stuck ON, or the circuit to be applied.