Cutlass Ciera Cruiser V6-3300 3.3L MFI VIN N (1993)
TCC Circuit
CIRCUIT DESCRIPTION:
The purpose of the Torque Converter Clutch (TCC) feature is to eliminate the power loss of the transmission converter stage when the vehicle is in
a cruise condition. This allows the convenience of the automatic transmission and the fuel economy of a manual transaxle.
Fused battery ignition is supplied to the TCC solenoid through the brake switch, and transmission third gear apply switch. The ECM will engage
TCC by grounding CKT 422 to energize the solenoid.
The TCC will engage when:
^
Engine warmed up.
^
Vehicle speed above a calibrated value (about 33 mph, 51 km/h).
^
Transmission 3rd gear switch open.
^
Throttle position sensor output not changing, indicating a steady road speed.
^
Transmission TCC in-line switch closed.
^
Brake switch closed.
TEST DESCRIPTION: Numbers below refer to circled numbers on the diagnostic chart.
1.
This test checks integrity of total circuit minus the TCC solenoid.
2.
This test checks for a faulty brake switch or open circuit 422.
DIAGNOSTIC AIDS:
If vehicle is road tested because of a TCC related problem, be sure the switch states do not change while in 4th gear because the TCC will
disengage. If switches change state, carefully check wire routing and connections. If the ECM, TCC solenoid, and control circuitry are functioning
correctly and the TCC still does not apply properly, the problem may be hydraulic or mechanical.
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