Component Diagnostic Charts (C-Charts) - Port Fuel Injection

Fig. 005 - Chart C-8A - Transmission/Transaxle Converter Clutch. (1 of 2):

Fig. 007 - WIRING DIAGRAM for Chart C-8A Transmission Converter Clutch. (1 of 2). VIN 3:

CHART C-8A

TRANSMISSION/TRANSAXLE CONVERTER CLUTCH (TCC)

3.8L "A & C" SERIES

FUEL INJECTION (PORT)

The purpose of the transmission/transaxle converter clutch feature is to eliminate the power loss of the torque converter stage when the vehicle is in a cruise condition. This allows the convenience of the automatic transmission/transaxle and the fuel economy of a manual transmission/transaxle. The heart of the system is a solenoid located inside the automatic transmission/transaxle which is controlled by the ECM.
When the solenoid coil is activated ("ON"), the transmission/transaxle converter clutch is applied which results in straight through mechanical coupling from the engine to transmission/transaxle. When the transmission/transaxle solenoid is deactivated, the transmission/transaxle converter clutch is released which allows the transmission/transaxle converter to operate in the conventional manner (fluidic coupling between engine and transmission).
The TCC will engage on a warm engine under given road load in 3rd and 4th gears.

1. Light off confirms transmission/transaxle third gear switch is open.
2. At 30 MPH the transmission/transaxle third gear switch should close. Test light will come on and confirm battery supply and closed brake switch.
3. Grounding the diagnostic test terminal with engine off should energize the TCC solenoid. This test checks the capability of the ECM to control the solenoid.
4. Solenoids are turned "ON" or "OFF" by the ECM internal electronic switches called "drivers". Each driver is part of a group of a group of four called "Quad-Drivers". Failure of one can damage any other driver within the set. Solenoid coil resistance must measure more than 20 ohms. Less resistance will cause early failure of the ECM "Driver". Using an ohmmeter, check the solenoid coil resistance of the following before installing a replacement ECM.
a. TCC Solenoid.

Fig. 006 - WIRING DIAGRAM for Chart C-8A Transmission Converter Clutch (1 of 2). VIN 3:

Fig. 013 - Chart C-8B - Transmission Converter Clutch (2 of 2). VIN 3:

CHART C-8B, TRANSMISSION CONVERTER CLUTCH (TCC)

1. Over 6 volts confirms ECM cruise signal voltage is OK and CKT 494 is not shorted to ground.
2. Over 6 volts indicates an open CKT 446, transmission connector, or a fourth gear switch stuck open.
3. With drive wheels at 50-55 mph, a voltage under 6 volts indicates CKT 446 is shorted to ground or faulty fourth gear switch if transmission is actually in fourth gear.
4. Checks to determine if problem with CKT 446 is an internal transmission problem.