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 powertrain control module (PCM) detects a 1-2-2-1 shift pattern, then
DTC P0757 sets. DTC P0757 is a type A DTC.
The number below refers to the step number 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 - 4.8L, 5.3L and 6.0L
|
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 - 4.8L, 5.3L and 6.0L
|
3
|
- Inspect the 2-3 shift solenoid/hydraulic circuit for the
following conditions:
• | 2-3 shift solenoid mechanically stuck OFF. |
• | 2-3 shift valve stuck in the released position. |
• | Damaged seals on the shift solenoid valves. |
- Clean and inspect the related valves, bores and the valve body for debris
or contamination restricting valve movement.
Refer to
Control Valve Body Disassemble
in the 4L60-E section of the Transmission
Unit Repair Manual.
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 - 4.8L, 5.3L and 6.0L
| System OK
|