Code P0740, TCC Circuit: Notes
WARNING: This page is about a different car, the 1995 Pontiac Trans Sport, 1995 Oldsmobile Silhouette, and 1995 Chevrolet Lumina APV. However, it is still accessible from the selected car via links, so may be relevant.
Control module monitors difference between engine speed and transaxle input shaft speed. With selector in D3 or D4 (indicated gear 3 or 4) and TCC locked, scan should display engine speed closely matching input speed. PWM solenoid is used to vary hydraulic pressure to converter clutch regulator valve which causes a smooth TCC engagement.
Code 740 will set when vehicle is in 3rd or 4th gear and, brake not applied, TCC is commanded by control module and engine speed-to-vehicle speed ratio does not indicate TCC has engaged. All these conditions must have been met for more than 10 seconds.
NOTE:
Test numbers refer to numbers on diagnostic chart.
- Checks if fault is caused by a bad solenoid or control circuit.
- Tests fuse, brake switch, battery power circuits to transaxle connector.
- Checks control module's ability to pulse PWM solenoid.