DTC P0756 2-3 Shift Solenoid Valve Performance 2.4L
Circuit Description
The 2-3 Shift Solenoid Valve (2-3 SS Valve) is a normally-open exhaust
valve that, in conjunction with the 1-2 Shift Solenoid Valve (1-2 SS Valve),
allows 4 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 four conditions:
| • | A stuck ON 2-3 SS Valve |
| • | A stuck OFF 2-3 SS Valve |
| • | A stuck ON 2-3 shift valve |
| • | A stuck OFF 2-3 shift valve |
When the PCM detects an actual gear ratio that does not agree with the
commanded gear, then DTC P0756 sets. DTC P0756 is a type A DTC.
Conditions for Setting the DTC
| • | No TP DTCs P0121, P0122 or P0123. |
| • | No VSS DTCs P0502 or P0503. |
| • | No A/T ISS DTCs P0716 or P0717. |
| • | No 1-2 shift solenoid electrical DTC P0753. |
| • | No 2-3 shift solenoid electrical DTC P0758. |
| • | No engine torque DTC P1644. |
| • | No TFP Val. Position Sw. DTC P1810. |
| • | The TFP Val. Position Sw. indicates D4, D3, D2 or D1. |
| • | The transmission fluid temperature is greater than 20°C (68°F). |
| • | The MAP is greater than 10 kPa. |
| • | Engine torque is greater than 14 N·m (10 lb ft) |
| • | The vehicle speed is greater than 8 km/h (5 mph). |
| • | The TP is greater than 8%. |
| • | All of the above conditions are true, and any one of the following
fail cases occurs: |
Case 1
| • | The PCM commands 1st gear and the gear ratio is 1:0.61-1:0.72
(4th gear) for 2 seconds. |
| • | The PCM commands 2nd gear and the gear ratio is 1:0.91-1:1.07
(3rd gear) for 2 seconds. |
Case 2
| • | The PCM commands 3rd gear and the gear ratio is 1:1.54-1:1.71
(2nd gear) for 3 seconds. |
| • | The PCM commands 4th gear and the gear ratio is 1:2.87-1:3.13
(1st gear) for 4 seconds. |
Action Taken When the DTC Sets
| • | The PCM illuminates the Malfunction Indicator Lamp (MIL). |
| • | The PCM commands maximum line pressure. |
| • | The PCM commands an immediate landing to 2nd gear. |
| • | The PCM inhibits TCC engagement. |
| • | The PCM freezes shift adapts from being updated. |
| • | DTC P0756 is stored in the PCM history. |
Conditions for Clearing the MIL/DTC
| • | The PCM turns OFF the MIL after three consecutive trips
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. |
| • | The PCM cancels the DTC default actions when the fault no longer
exists and the ignition is OFF long enough in order to power down the PCM. |
Diagnostic Aids
If you clear DTC P0756, and then cannot reset DTC P0756, inspect
for the following conditions:
| • | Restricted oil circuits |
| | Refer to Shift Solenoid Valve State and Gear Ratio
. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step verifies that the gear ratio is correct for the commanded
gear.
-
This step tests for a mechanical or hydraulic condition causing the
2-3 SS valve to be stuck OFF, or the circuit to be released.
-
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.
DTC P0756 2-3 Shift Solenoid Valve -- Performance (2.4L)
Step
| Action
| Value(s)
| Yes
| No
|
1
| Was the Powertrain On-Board Diagnostic
(OBD) System Check performed?
| --
|
Go to Step
2
| Go to
Powertrain On Board Diagnostic (OBD) System Check
|
2
| Have you performed the transmission fluid checking procedure?
| --
|
Go to Step 3
| Go to
Transmission Fluid Check
|
3
|
- Install the Scan Tool
.
- 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. Using the Clear Info function will
erase the stored Freeze Frame and Failure Records from the PCM.
- Record the DTC Freeze Frame and Failure Records, then clear the DTCs.
- Use the scan tool snapshot mode in order to record current gear
and gear ratio.
- Drive the vehicle in D4, in order to obtain a 2-3 shift with a
TP greater than 8% and a vehicle speed greater than 8 km/h (5 mph)
for 5 seconds.
Are the gear ratios within the given gear range?
| 1st: 2.87-3.13
4th: 0.61-0.72
| Go to Diagnostic Aids
|
Go to Step 4
|
4
| Does the engine labor at start-off, or is 3rd gear indicated
when 1st gear is commanded?
| --
|
Go to Step
6
|
Go to Step 5
|
5
|
- Inspect the 2-3 shift circuit for the following conditions:
| • | 2-3 Shift Solenoid Valve (2-3 SS Valve) mechanically stuck OFF. |
| • | Damaged 2-3 SS Valve o-ring |
| • | 2-3 SS Valve stuck in the released position. |
- Repair the circuit.
Refer to Unit Repair.
Did you find and correct the condition?
| --
|
Go to Step 7
| --
|
6
|
- Inspect the 2-3 shift circuit for the following conditions:
| • | 2-3 SS Valve mechanically stuck ON. |
| • | 2-3 SS Valve stuck in the applied position. |
- Repair the circuit.
Refer to Unit Repair.
Did you find and correct the condition?
| --
|
Go to Step 7
| --
|
7
| In order
to verify your repair, perform the following procedure:
- Select DTC.
- Select Clear Info.
- Operate the vehicle under the following conditions:
| • | Drive the vehicle in D4. |
| • | Allow the transmission to shift through all the gears. |
| • | Monitor the current gear and gear ratios. The actual gear ratios
must match the commanded gears for 0.75 seconds, for all gears. |
- Select Specific DTC. Enter DTC P0756.
Has the test run and passed?
| --
| System OK
|
Begin the diagnosis
again. Go to Step 1
|
DTC P0756 2-3 Shift Solenoid Valve Performance 3.1L
Circuit Description
The 2-3 Shift Solenoid Valve (2-3 SS Valve) is a normally-open exhaust
valve that, in conjunction with the 1-2 Shift Solenoid Valve (1-2 SS Valve),
allows 4 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 four conditions:
| • | A stuck ON 2-3 SS Valve |
| • | A stuck OFF 2-3 SS Valve |
| • | A stuck ON 2-3 shift valve |
| • | A stuck OFF 2-3 shift valve |
When the PCM detects an actual gear ratio that does not agree with the
commanded gear, then DTC P0756 sets. DTC P0756 is a type A DTC.
Conditions for Setting the DTC
| • | No TP DTCs P0121, P0122 or P0123. |
| • | No VSS DTCs P0502 or P0503. |
| • | No A/T ISS DTCs P0716 or P0717. |
| • | No 1-2 shift solenoid electrical DTC P0753. |
| • | No 2-3 shift solenoid electrical DTC P0758. |
| • | No engine torque DTC P1644. |
| • | No TFP Val. Position Sw. DTC P1810. |
| • | The TFP Val. Position Sw. indicates D4, D3, D2 or D1. |
| • | The transmission fluid temperature is greater than 20°C (68°F). |
| • | The vehicle speed is greater than 8 km/h (5 mph). |
| • | The TP is greater than 8%. |
| • | All of the above conditions are true, and any one of the following
fail cases occurs: |
Case 1
| • | The PCM commands 1st gear and the gear ratio is 1:0.61-1:0.72
(4th gear) for 2 seconds. |
| • | The PCM commands 2nd gear and the gear ratio is 1:0.91-1:1.07
(3rd gear) for 2 seconds. |
Case 2
| • | The PCM commands 3rd gear and the gear ratio is 1:1.54-1:1.71
(2nd gear) for 3 seconds. |
| • | The PCM commands 4th gear and the gear ratio is 1:2.87-1:3.13
(1st gear) for 4 seconds. |
Action Taken When the DTC Sets
| • | The PCM illuminates the Malfunction Indicator Lamp (MIL). |
| • | The PCM commands maximum line pressure. |
| • | The PCM commands an immediate landing to 2nd gear. |
| • | The PCM inhibits TCC engagement. |
| • | The PCM freezes shift adapts from being updated. |
| • | DTC P0756 is stored in the PCM history. |
Conditions for Clearing the MIL/DTC
| • | The PCM turns OFF the MIL after three consecutive trips
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. |
| • | The PCM cancels the DTC default actions when the fault no longer
exists and the ignition is OFF long enough in order to power down the PCM. |
Diagnostic Aids
If you clear DTC P0756, and then cannot reset DTC P0756, inspect
for the following conditions:
| • | Restricted oil circuits |
| | Refer to Shift Solenoid Valve State and Gear Ratio
. |
Test Description
The numbers below refer to the step numbers on the diagnostic table.
-
This step verifies that the gear ratio is correct for the commanded
gear.
-
This step tests for a mechanical or hydraulic condition causing the
2-3 SS valve to be stuck OFF, or the circuit to be released.
-
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.
DTC P0756 2-3 Shift Solenoid Valve -- Performance (3.1L)
Step
| Action
| Value(s)
| Yes
| No
|
1
| Was the Powertrain On-Board Diagnostic
(OBD) System Check performed?
| --
|
Go to Step
2
| Go to
Powertrain On Board Diagnostic (OBD) System Check
|
2
| Have you performed the transmission fluid checking procedure?
| --
|
Go to Step 3
| Go to
Transmission Fluid Check
|
3
|
- Install the Scan Tool
.
- 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. Using the Clear Info function will
erase the stored Freeze Frame and Failure Records from the PCM.
- Record the DTC Freeze Frame and Failure Records, then clear the DTCs.
- Use the scan tool snapshot mode in order to record current gear
and gear ratio.
- Drive the vehicle in D4, in order to obtain a 2-3 shift with a
TP greater than 8% and a vehicle speed greater than 8 km/h (5 mph)
for 5 seconds.
Are the gear ratios within the given gear range?
| 1st: 2.87-3.13
4th: 0.61-0.72
| Go to Diagnostic Aids
|
Go to Step 4
|
4
| Does the engine labor at start-off, or is 3rd gear indicated
when 1st gear is commanded?
| --
|
Go to Step
6
|
Go to Step 5
|
5
|
- Inspect the 2-3 shift circuit for the following conditions:
| • | 2-3 Shift Solenoid Valve (2-3 SS Valve) mechanically stuck OFF. |
| • | Damaged 2-3 SS Valve o-ring |
| • | 2-3 SS Valve stuck in the released position. |
- Repair the circuit.
Refer to Unit Repair.
Did you find and correct the condition?
| --
|
Go to Step 7
| --
|
6
|
- Inspect the 2-3 shift circuit for the following conditions:
| • | 2-3 SS Valve mechanically stuck ON. |
| • | 2-3 SS Valve stuck in the applied position. |
- Repair the circuit.
Refer to Unit Repair.
Did you find and correct the condition?
| --
|
Go to Step 7
| --
|
7
| In order
to verify your repair, perform the following procedure:
- Select DTC.
- Select Clear Info.
- Operate the vehicle under the following conditions:
| • | Drive the vehicle in D4. |
| • | Allow the transmission to shift through all the gears. |
| • | Monitor the current gear and gear ratios. The actual gear ratios
must match the commanded gears for 0.75 seconds, for all gears. |
- Select Specific DTC. Enter DTC P0756.
Has the test run and passed?
| --
| System OK
|
Begin the diagnosis
again. Go to Step 1
|
