| Table 1: | Shift Solenoid Valid Combination Table |
DTC Description
This diagnostic procedure covers the following DTCs:
| • | DTC P0756--2-3 Shift Solenoid B Performance or Stuck OFF |
| • | DTC P0757--2-3 Shift Solenoid B Performance or Stuck ON |
| • | DTC P0758--2-3 Shift Solenoid B Electrical |
Circuit Description
The 2-3 shift solenoid B controls the fluid flow acting on the 2-3 shift valve. The 2-3 shift solenoid B is a normally open-exhaust valve that is used with the 1-2 shift solenoid A valve, to allow four different shifting combinations. The solenoid attaches to the control valve body within the transmission. The 2-3 shift solenoid B receives ignition voltage through circuit 339. The powertrain control module (PCM) controls the solenoid by providing the ground path on circuit 1223.
When the PCM detects a shift pattern other than what is expects, or a fault in the electrical circuit, a 2-3 shift solenoid A DTC sets.
Conditions for Running DTCs
P0756
| • | No TPS, VSS, TCC solenoid, 1-2 shift solenoid, 2-3 shift solenoid, other 2-3 shift solenoid, or TFP manual valve position switch DTCs are set. |
| • | The engine speed is greater than 450 RPM for 5 seconds. |
| • | The engine is not in fuel cut-off. |
| • | The gear range is D4. |
| • | The TP angle is greater than 10 percent. |
| • | The transmission fluid temperature is 20-130°C. |
| • | The system voltage is 10.0-18.0 volts. |
P0757
| • | No TPS, VSS, TCC solenoid, 1-2 shift solenoid, 3-2 shift solenoid, other 2-3 shift solenoid, or TFP manual valve position switch DTCs are set. |
| • | The engine speed is greater than 450 RPM for 5 seconds. |
| • | The engine is not in fuel cut-off. |
| • | The gear range is D4. |
| • | The TP angle is greater than 10 percent. |
| • | The transmission fluid temperature is 20-130°C. |
| • | The system voltage is 10-18 volts. |
| • | The transmission output speed is 150 RPM or greater. |
P0758
| • | The system voltage is between 8.0-18.0 volts. |
| • | The engine speed is greater than 300 RPM for 5 seconds. |
| • | The engine is not in fuel cut-off. |
Conditions for Setting DTCs
P0756
DTC P0756 sets if both of the following conditions occur:
Condition 1
| • | The PCM commands first gear for 2 seconds. |
| • | The estimated gear ratio is 0-1.4. |
| • | The engine torque is 68-542 N·m. |
| • | The transmission output speed is 200 RPM or greater. |
| • | The TCC slip speed is -3,000 to +200 RPM. |
| • | All conditions are met for 1 second. |
Condition 2
| • | The PCM commands second gear for 1 second. |
| • | The estimated gear ratio is 0.9-1.2. |
| • | The engine torque is 68-542 N·m. |
| • | the speed ratio is 0.5 or greater. Speed ratio is engine speed divided by transmission output speed. |
| • | All conditions are met for 2 seconds. |
P0757
DTC P0757 sets if both of the following conditions occur:
Condition 1
| • | The PCM commands third gear for 1 second. |
| • | The estimated gear ratio is 1.6-1.8. |
| • | Speed ratio is 0.5 or greater. Speed ratio is engine speed divided by transmission output speed. |
| • | Engine torque 68-542 N·m. |
| • | All conditions are met for 2 seconds. |
Condition 2
| • | The PCM command fourth gear for 1 second. |
| • | The estimated gear ratio 1.8-3.3. |
| • | Speed ratio is 0.5 or greater. Speed ratio is engine speed divided by transmission output speed. |
| • | Engine torque is 0-542 N·m. |
| • | All conditions are met for 2 seconds. |
P0758
| • | The PCM commands the solenoid ON and the voltage input remains high (12 volts). |
| OR |
| • | The PCM commands the solenoid OFF and the voltage input remains low (0 volts). |
Conditions for Clearing the DTCs
The 2-3 shift solenoid B DTCs are Type A DTCs. Refer to Diagnostic Starting Point - Automatic Transmission for Action Taken when Type A DTCs set and Conditions for Clearing Type A DTCs.
Additional Information
| • | Verify that the transmission shift pattern complies with the shift pattern charts. Refer to Functional Test. Other internal transmission failures may cause more than one shift to occur. |
| • | Refer to Transmission General Information for details of the 2-3 shift solenoid B operation. |
| • | For an intermittent fault condition, refer to Intermittent Conditions. |
| • | Since a fault condition in a wiring connector may trigger DTCs, always test the connectors related to this diagnostic procedure for shorted terminals or poor wiring connection before replacing any component. Refer to Testing for Intermittent Conditions and Poor Connections for information on electrical fault diagnosis. |
Gear | 1-2 Shift Solenoid A | 2-3 Shift Solenoid B | Gear Ratio |
|---|---|---|---|
1 | ON | ON | 3.059:1 |
2 | OFF | ON | 1.625:1 |
3 | OFF | OFF | 1.000:1 |
4 | ON | OFF | 0.696:1 |
Test Description
The following numbers below refer to the step numbers on the diagnostic chart.
5 A mechanical fault causes DTC P0756 or P0757 to set.
10 This diagnostic table only tests the 2-3 shift solenoid B circuits outside the transmission. Check for damaged wiring or poor connections inside the transmission assembly before replacing the 2-3 shift solenoid B. Measure the resistance of the 2-3 shift solenoid B. Refer to Transmission General Specifications.
Step | Action | Yes | No | ||||
|---|---|---|---|---|---|---|---|
1 | Was the Main Diagnostic Table performed? | Go to Step 2 | |||||
2 |
Does DTC P0756, P0757, or P0758 fail this ignition cycle? | Go to Step 3 | Refer to Diagnostic Aids for the 2-3 Shift Solenoid B DTCs | ||||
3 | Is DTC P0756 and/or P0757, but not P0758 set? | Go to Step 6 | -- | ||||
4 | Is DTC P0758 set? | Go to Step 5 | -- | ||||
5 | Inspect the shift solenoid/hydraulic circuit for the following conditions:
Refer to Functional Test. Was any fault found and rectified? | Go to Step 12 | Refer to Diagnostic Aids for the 2-3 Shift Solenoid B DTCs. | ||||
6 |
Does the test lamp illuminate? | Go to Step 7 | Go to Step 9 | ||||
7 |
Does the test lamp illuminate ON and OFF when the 2-3 shift solenoid B is commanded ON and OFF? | Go to Step 12 | Go to Step 11 | ||||
8 | Test the 2-3 shift solenoid B control circuit for open circuit, short to ground, high resistance, or short to voltage fault condition. Refer to Testing for Intermittent Conditions and Poor Connections for information on electrical fault diagnosis. Was any fault found and rectified? | Go to Step 12 | Go to Step 11 | ||||
9 | Repair the open circuit, short to ground, high resistance, or short to voltage fault condition in the 2-3 shift solenoid B ignition voltage circuit. Refer to Wiring Repairs for information on electrical wiring repair procedures. Was the repair completed? | Go to Step 12 | -- | ||||
10 |
Important: Check for damaged wiring (short to ground, short to voltage, high resistance, or open circuit) or poor connections inside the transmission assembly before replacing the 2-3 shift solenoid B. Replace the 2-3 shift solenoid B. Refer to 2-3 Shift Solenoid Valve Replacement. Was the repair completed? | Go to Step 12 | -- | ||||
11 | Replace the PCM. Refer to Powertrain Control Module Replacement. Was the repair completed? | Go to Step 12 | -- | ||||
12 |
Do any 2-3 shift solenoid B DTCs fail this ignition cycle? | Go to Step 2 | Go to Step 13 | ||||
13 | Using Tech 2, select the DTC Display function Are there any DTCs displayed? | Go to the appropriate DTC Table | System OK | ||||
When all diagnosis and repairs are completed, check the powertrain management system for correct operation. | |||||||
