Cutlass V6-260 4.3L DSL (1984)
Fig. 051 - Chart For TCC Check With 125C.
1.
Checks for 12 volts at transmission TCC connector. Test light should not be "ON." If the light was "ON," there is either a short to 12 volts or a
faulty ECM.
2.
Checks for TCC engagement signal to transmission. Light should be "ON" above TCC engagement speed.
3.
Checks for TCC engagement signal at ECM. Results will indicate an open or faulty ECM. If light flashes, ECM is trying to engage TCC but is
shorted in the wire or solenoid. The ECM has a short protection circuit that will protect TCC engage signal by cutting TCC signal "OFF" when
short is detected.
4.
Checks for proper 3rd gear signal to engage TCC. Voltage at ECM terminal "U" will be below one volt until the 3rd gear switch opens. When the
transmission shifts into 3rd, the switch opens and voltage at "U" should be near battery voltage if the circuit and switch are normal.
Chart For TCC Check With THM 2004R: 1984 Vin V (4.3L)
