The 2-3 shift solenoid (SS) valve controls the fluid flow acting on the 2-3 shift valves. The 2-3 SS valve is a normally-open exhaust valve that is used with the 1-2 SS valve in order to allow four different shifting combinations.
When the PCM detects a 1-2-2-1 shift pattern, then DTC P0757 sets. DTC P0757 is a type A DTC.
The numbers below refer to the step numbers on the diagnostic table.
DTC P0757
Step
| Action
| Value(s)
| Yes
| No
|
1
| Did you perform the Diagnostic System Check - Engine Controls?
| --
| Go to
Step 2
| Go to
Diagnostic System Check - Engine Controls
in Engine Controls - 6.0L (LQ4)
|
2
|
- Install a scan tool.
- Turn ON the ignition, with the engine OFF.
Important: Before clearing the DTC, use the scan tool in order to record the Freeze Frame and Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the PCM.
- Record the DTC Freeze Frame and Failure Records.
- Clear the DTC.
- Drive the vehicle in D4 range under the following condition:
Accelerate the vehicle, ensuring that the PCM commands 1st, 2nd, 3rd and 4th gears.
Did you detect a 1-2-2-1 shift pattern?
| --
| Go to
Step 3
| Go to
Intermittent Conditions
in Engine Controls - 6.0L (LQ4)
|
3
| Inspect the shift solenoid/hydraulic circuit for the following conditions:
• | An internal malfunction |
• | Damaged seals on the shift solenoid valve |
Did you find and correct the condition?
| --
| Go to
Step 4
| --
|
4
| Perform the following procedure in order to verify the repair:
- Select DTC.
- Select Clear Info.
- Drive the vehicle in D4 range under the following condition, only if traffic and road conditions permit:
Hold the throttle at 15% and accelerate to 80 km/h (55 mph).
- Select Specific DTC.
- Enter DTC P0757.
Has the test run and passed?
| --
| Go to
Step 5
| Go to
Step 2
|
5
| With the scan tool, observe the stored information, capture info, and DTC Info.
Does the scan tool display any DTCs that you have not diagnosed?
| --
| Go to
Diagnostic Trouble Code (DTC) List
in Engine Controls - 6.0L (LQ4)
| System OK
|