DTC 36

Transaxle Shift Circuit:

Code 36 Diagnostic Chart:

Circuit Description:
The 4T60 E transaxle 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 operation. The other two solenoids are for TCC operation only. We will deal with shift control only here.

When the ignition switch is turned "ON," both Solenoids "A" and "B" receive 12 volts from CKT 250. The PCM will ground CKT 1223 and CKT 1222 for 1st gear until a shift to second gear is commanded. When vehicle speed and TPS reach calibrated values the PCM will turn "OFF" the ground for Solenoid "A" and 2nd gear is engaged. Further increases in speed will result in the PCM turning "OFF" the 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 the PRNDL position indicates manual low has been selected the PCM will keep both Solenoids "A" and "B" energized until 5400 rpm, when the PCM will force a shift by de-energizing Solenoid "A". Manual 2nd and manual 3rd are controlled hydraulically within the transaxle.

Code 36 will set if:

^ Solenoid "B" is failed in the "OFF" position, which will cause the transmission to be in 4th gear, and:
- Desired gear is 1st - No Code 21, 22 or 24 present.
- TPS is greater than 40% - Vehicle acceleration rate does not indicate 1st gear.

^ Vehicle speed is between 3 and 20 mph
- Above conditions for 2 seconds.
- Engine speed is greater than 2000 rpm.

OR

^ Solenoid "B" is failed in the "ON" position which will cause the transmission to be in 1st gear and:
- Desired gear is 4th - LV8 is less than 80.
- PRNDL is in 3rd or 4th - Above conditions for over 2 seconds.
- TPS is greater than 10%.
- No Code 31, 21 or 22 present.
- Engine speed divided by vehicle speed does not indicate 4th gear.

Code 36 does not illuminate the "Service Engine Soon" light.

NOTE: When Code 36 is set, the transaxle will be forced into 3rd gear. If a Code 36 is set due to a grounded CKT 1223, you will have 1st and 2nd gear operation only.

If CKT 1223 is open, you will have 3rd and 4th gear operation only. When the fault goes away, you will have normal operation for the balance of the key cycle.