P0756

Diagnostic Chart:

Diagnostic Chart (cont'd):

Diagnostic Chart:

Shift Solenoid:

CIRCUIT DESCRIPTION

The 2-3 Shift Solenoid Valve (2-3 SS Valve) controls the fluid flow acting on the 2-3 shift valves. The solenoid is a normally-open exhaust valve. The combination of the 2-3 SS Valve and the 1-2 Shift Solenoid Valve allows four different shift combinations.

When the PCM detects a 1-2-2-1 only shift pattern or a 4-3-3-4 only shift pattern depending on the mechanical failure, then DTC P0756 sets. DTC P0756 is a type B DTC.


CONDITIONS FOR SETTING THE DTC

- No Throttle Position (TP) DTCs P0122 or P0123

- No Vehicle Speed Sensor (VSS) DTC P0502

- No Transmission Fluid Temperature (TFT) Sensor DTCs P0712 or P0713

- No TFP Valve Position Switch DTC P1810

- The vehicle speed is greater than 32 km/h (20 mph).

- The gear range is D4, D3, D2 or D1.

- The engine speed is greater than 400 RPM for 8 seconds and not in fuel cutoff.

- The transmission fluid temperature is greater than 20° (68°F).

1. All of the above conditions are met and either one of the following fail-conditions occurs:

Condition 1

- The TP angle is greater than 45%.

- First gear is commanded.

- The speed ratio is less than 115 (speed ratio is engine speed + output speed).

- All conditions are met for 1 second.

Condition 2

- The TP angle is greater than 18%.

- Fourth gear is commanded.

- The speed ratio is greater than 100 (speed ratio is engine speed + output speed).

- Third gear speed ratio is greater than the last 2nd gear speed ratio minus 0.2.

- Third gear TCC slip speed is greater than or equal to the last 2nd gear TCC slip speed plus 200 RPM for 1.3 seconds.

- Discontinue the test if the time since shift commanded is 6 seconds.

- All conditions are met for 2 seconds.

ACTION TAKEN WHEN THE DTC SETS

The PCM illuminates the Malfunction Indicator Lamp (MIL).


CONDITIONS FOR CLEARING THE MIL/DTC

A scan tool can clear the DTC from the PCM history. The PCM clears the DTC from the PCM history if the vehicle completes 40 warm-up cycles without a failure reported.


DIAGNOSTIC AIDS

- Verify that the transmission meets the specifications in the Shift Speed.

- Other internal transmission failures may cause more than one shift to occur.

TEST DESCRIPTION

The numbers below refer to the step numbers on the diagnostic chart.

2. Step 2 verifies that the TFP Valve Position Switch is functioning normally.

3. Step 3 tests for a selected gear ratio vs a ratio not obtainable under normal driving conditions.