FW: Testing an ISV

[Tom Christiansen]

Hi,

>does the ISV respond to different voltages, or what?

The ECU controls the ISV solenoid through pulse width modulation (PWM).
This means that the signal to the valve will change rapidly (at about 100Hz
in my '87 5kq) between two fixed values, 0V and 12V. The solenoid acts like
an inductor and will average the current, thus, allowing the ECU to
continuously control the setting on the ISV.

>I have an old train transformer from a model railroad that has a variable
>output from 0-16V.  If I hooked that up to the ISV and varied the voltage,
>should the disk move different amounts?

Nope. You can make it move from closed to open and that's it.

Tom