911 Carrera S Cabriolet (997) F6-3.8L (2007)
Converter Lockup Clutch
Under several driving conditions depending on engine speed, -load and gear the converter lockup clutch is engaged with a defined slipping rate to have a
decoupling of the engine vibrations from the powertrain (for comfort reasons). During slipping operating conditions the TCM calculates every 20 ms
with the parameters engine speed, turbine speed, engine torque (calculated) and converter characteristic the frictional power, which is generated in the
converter lockup clutch. If the frictional power exceeds a specified threshold a counter is activated in 20 ms intervals, if the frictional power falls below
the threshold, the counter counts backwards.
If the counter value reaches 7, a malfunctioning converter lockup clutch is detected and the corresponding fault code stored.
Solenoid Valve of the Converter Lockup Clutch
The solenoid valve of the converter lockup clutch is controlled within is minimum (5%) and maximum keying ratio (94%). A malfunction is detected and
the corresponding fault code is stored if after a time of 160 ms one of the following occurs:
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short circuit of shift valve against ground
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short circuit of shift valve against battery voltage
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short circuit of power stage
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broken cable of shift valve
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broken cable of power stage
Control Solenoid Valves
The control solenoid valves are monitored against the following:
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short circuit of the valves against battery voltage
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internal short circuit of the valves
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short circuit of valves against ground
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broken cable of powerstages
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short circuit of powerstages
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broken cable of valves
The monitoring of the malfunctions is partely performed by measuring the gradient of the nominal voltage control. If the gradient is to high or if one of
the above malfunctions occurs for more than 300 ms, malfunctioning is detected and the corresponding fault code is stored.
Transmission Control Module Inputs/Outputs: