DTC P0756 2-3 (B) Shift Solenoid Performance. Buick Skylark 1996

For 1990-2009 cars only

Makes 🢒 Buick 🢒 1996 🢒 Skylark 🢒 DTC 🢒 DTC P0756 2-3 (B) Shift Solenoid Performance

DTC P0756 2-3 (B) Shift Solenoid Performance 2.4L VIN T

Table 1:	Shift Solenoid State and Gear Ratio
Table 2:	DTC P0756 2-3 Shift Solenoid Performance

Automatic Transmission Components
Automatic Transmission Controls Schematics
OBD II Symbol Description Notice

Circuit Description

The Powertrain Control Module (PCM) monitors the commanded gear and speed ratio in order to identify a 2-3 Shift Solenoid Valve (2-3 SS Valve) problem.

When the PCM detects a gear other than 1st gear when 1st gear is commanded, then DTC P0756 sets. When the PCM detects 1st gear when 4th gear is commanded, then DTC P0756 sets. DTC P0756 is a type B DTC.

Conditions for Setting the DTC

•	No TP DTCs P0122 or P0123

•	No VSS DTC P0502 or P0503

•	No TCC solenoid DTCs P0740 or P0742.

•	No 1-2 solenoid electrical DTC P0753.

•	No 2-3 solenoid electrical DTC P0758.

•	No TCC PWM solenoid electrical DTC P1860.

•	The transmission range is D4.

•	The ECT is 40-120°C (104-248°F).

•	The vehicle speed is more than 11 km/h (7 mph).

•	The engine speed is more than 500 RPM for 5 seconds.

•	The engine is not in fuel shut off.

•	The MAP is 20-100 kPa (3-14 psi).

All of the above must be true and two of the following fail cases must occur three times:

Failure Criteria

Case 1

•	1st gear is commanded for more than 2 seconds.

•	The TCC slip speed is -4064 to 200 RPM.

•	The Output speed is 700-1300 RPM.

•	The speed ratio is 0.76-3.00.

•	The throttle position is more than 18%.

•	All of the above occurs for more than 1.5 seconds.

Case 2

•	2nd gear is commanded for more than 2 seconds.

•	The TCC slip speed is -1000 to 200 RPM.

•	The output speed is 1000-2100 RPM.

•	The speed ratio is 1.1-2.0.

•	The throttle position is more than 18%.

•	All of the above occurs for more than 2 seconds.

Case 3

•	3rd gear is commanded for 2.5-7.5 seconds.

•	The TCC slip speed is 500 RPM more than the slip speed in 2nd gear.

•	The speed ratio is not more than 0.5 less than the speed ratio in 2nd gear.

•	The throttle position is 18-45% and constant by 5%.

•	All of the above occurs for more than 2.5 seconds.

Case 4

•	4th gear is commanded for more than 1.5 seconds.

•	The TCC slip speed is 1600-4096 RPM.

•	The output speed is 1650-8192 RPM.

•	The speed ratio is 2-4.

•	The throttle position is more than 14%.

•	All of the above occurs for more than 2 seconds.

Action Taken When the DTC Sets

The PCM illuminates the Malfunction Indicator Lamp (MIL) after two consecutive trips with a failure reported.

Conditions for Clearing the DTC

•	The PCM turns OFF the MIL after three consecutive ignition cycles without a failure reported.

•	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

•	Check for PRNDL DTC P0705. DTC P0705 affects transmission operation. This may set DTC P0756 falsely.

•	Inspect the transmission fluid for sediment.

•	Inspect the transmission filter for debris.

Shift Solenoid State and Gear Ratio

Gear	1-2 Shift Solenoid	2-3 Shift Solenoid	Gear Ratio
1st	ON	ON	2.921:1
2nd	OFF	ON	1.568:1
3rd	OFF	OFF	1.000:1
4th	ON	OFF	0.705:1
Reverse	ON	ON	2.385:1

Test Description

The number below refers to the step number on the diagnostic chart.

Once the DTC is verified, replace the 2-3 shift solenoid.

DTC P0756 2-3 Shift Solenoid Performance

Step

Action

Value(s)

Yes

Was the Powertrain On-Board Diagnostic (OBD) System Check performed?

Go to Step 2

Go to Powertrain On Board Diagnostic (OBD) System Check

Have you performed the fluid checking procedure?

Go to Step 3

Go to Transmission Fluid Check

Install the scan tool (tech 1) ®.
With the engine OFF, turn the ignition switch to the RUN position.

Important: Before clearing the DTCs, use the scan tool in order to record the Freeze Frame and Failure Records for reference. The Clear Info function will erase the data.

Record the DTC Freeze Frame and Failure Records.
After verifying that the DTC has set, replace the 2-3 Solenoid.

Refer to 2-3 Solenoid Valve Replacement, in On-Vehicle Service.

Is the replacement complete?

Go to Step 4

In order to verify your repair, perform the following procedure:

Select DTC.
Select Clear Info.
Operate the vehicle under the following conditions:

•	The engine coolant temperature is 40-120°C (104-248°F).

•	The engine speed is more than 500 RPM for 5 seconds.

•	The engine is not in fuel shut off.

•	The gear range is D4.

•	MAP is 20-100 kPa (3-14 psi).

•	The vehicle speed is more than 11 km/h (7 mph).

•	All of the following pass criteria must be true:

•

Case 1

-	First gear is commanded.

-	The throttle position is more than 18%.

-	The speed ratio is 3.5-5.0.

-	The TCC slip speed is 400-2700 RPM.

-	The output speed is 700-1300 RPM.

-	All of the above occur for more than 1.5 seconds.

•

Case 2

-	Fourth gear is commanded.

-	The throttle position is more than 12%.

-	The speed ratio is 0.76-1.25.

-	The TCC slip speed is -20 to 700 RPM.

-	The output speed is 1500-2800 RPM.

-	All of the above occur for more than 3 seconds.

Select Specific DTC. Enter DTC P0756.

Has the test run and passed?

System OK

Begin the diagnosis again. Go to System Diagnosis Charts:

First and Second Gear Only - 2-3 Solenoid Stuck On

Third and Fourth Gear Operation

DTC P0756 2-3 (B) Shift Solenoid Performance 3.1L VIN M

Table 1:	Shift Solenoid State and Gear Ratio
Table 2:	DTC P0756 2-3 Shift Solenoid Performance