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The torque converter impeller clutch modulating valve is a three-way proportional pressure-control valve. It is also a PWM solenoid controlled by the powertrain ECM. It functions the same as the lockup modulated valve in respect to proportion of pressure to current supply except in reverse proportion. The lower the ECM current, the higher the pressure signal to the impeller clutch. Refer back to Figure 11-46, component number 9. When the ECM sends a current signal to the solenoid valve, oil pressure is reduced at the impeller clutch piston. This causes the friction discs and plates to slip between the torque converter housing and the impeller. When the impeller slips, less oil is forced to the turbine. With less oil force on the turbine, there is less torque output from the torque converter, reducing rim-pull and wheel slip.