Diagnostic Chart (Functional Check)

4T60E Transaxle Shift Solenoid Diagnostic Chart:

Torque Converter Clutch Circuit:

Shift Solenoid Operating Sequence:

CIRCUIT DESCRIPTION
The 4T60E transaxle uses shift solenoid A and shift solenoid B to control shifting. Use the supplied shift solenoid operating sequence chart for solenoid operating sequence. The Powertrain Control Module (PCM) monitors the Throttle Position (TP) sensor, vehicle speed and engine speed (RPM) to determine the correct shift points.

If the trans range switch Park Reverse Neutral Drive Low (PRNDL) inputs indicate manual low position, the PCM will keep both shift solenoids energized until 5400 RPM at which point the PCM will force a shift by de-energizing the shift solenoid A. Manual 2nd and manual 3rd are controlled hydraulically within the transaxle.

CHART TEST DESCRIPTION
Number(s) below refer to circled number(s) on the diagnostic chart.
1. With key "ON"/engine "OFF," the PCM should be commanding 1St gear (both shift solenoid control circuits grounded).
2. Ensures that the PCM can control the ground to shift solenoid A properly.
3. Ensures that the PCM can control the ground to shift solenoid B.
4. Do not measure resistance until the ignition has been "OFF" for at least 10 seconds to ensure that the PCM has powered down completely.


DIAGNOSTIC AIDS
If the PCM, control circuitry, and shift solenoids are functioning properly and the transaxle still does not shift correctly, the problem may be hydraulic or mechanical.

4th gear may be disabled and transaxle shift timing altered if the vehicle is operating in "Hot Mode." "Hot Mode" will be in effect when transaxle temperature exceeds 130°C (266°F).