Code P0755, Transmission Shift Solenoid "B"
The 4T60E is an electronically shifted transaxle. Within the transaxle are 4 solenoids for shift and TCC control. Solenoid "A" is energized for 1st and 4th gear operation. Solenoid "B" is energized for 1st gear as well as 2nd gear operations. The other 2 solenoids are for TCC operation. This diagnostic chart deals with shift control solenoids only.
When ignition is on, both solenoids "A" and "B" receive 12 volts. PCM will ground "A" and "B" circuits for 1st gear until a shift to 2nd gear is commanded. When vehicle speed and TP sensor reach calibrated values, PCM will turn off ground for solenoid "A" and 2nd gear is engaged. Further increase in vehicle speed will cause PCM to turn off ground for solenoid "B", engaging 3rd gear. In 3rd gear, both solenoids are de-energized. In 4th gear, only solenoid "A" is energized.
All PRNDL indications are ignored as far as transaxle shifting is concerned except for manual low gear. If PRNDL inputs indicate manual low has been selected, PCM will keep both solenoids "A" and "B" energized until approximately 5400 RPM, when PCM will force a shift by de-energizing solenoid "A". Manual 2nd and manual 3rd are controlled hydraulically within transaxle.
Code P0755 will set when the following conditions are present.
- Shift "B" is failed in off position, causing transaxle to be in 4th gear and: - Desired gear is 1st. - Throttle angle is greater than 3 percent. - VSS is greater than 5 MPH. - Codes P0122, P0123, P0501 or P0502 are not set. - Engine speed divided by vehicle speed does not indicate 1st gear. - Above conditions for 3.5 seconds.
Or
- Shift "B" is failed in on position, causing transaxle to be in 1st gear and: - Desired gear is 4th. - PRNDL is in 3rd 0r 4th. - Throttle angle is greater than 10 percent. - Codes P0122, P0123 or P0705 are not set. - Engine speed divided by vehicle speed does not indicate 4th gear (LV8 less than 80). - Above conditions for 2 seconds.
When Code P0755 is set, transaxle will be forced into 3rd gear and will not allow TCC. If Code P0755 is set due to a grounded "B" solenoid circuit, only 1st, 2nd and 3rd gear operation will be available. If circuit is open, only 3rd and 4th gear operation will be available. When the fault goes away, normal operation will be available for the balance of the key cycle. Code P0755 does not illuminate the Malfunction Indicator Light (MIL).