bad idle control module 380se?

[earl orchard]

Hi all
i am still dealing with a on again off again high idle with my 1985 w126 380se m116,the car will some times start and idle normal(500-650 rpm)
but other times it will stick at 1500 rpm in park 1000 in drive after you start it ,or after about 5 minutes of normal idle( 500-650 rpm )the idle will zoom up to 1500 in park 1000 in drive. i tested the idle control valve and found that during normal idle the thing is getting about 12 volts and during high idle its getting 0 volts,if i hook up a 9 volt to the ICV(if its in high idle) the car will idle were it should. i have found in the FSM a test procedure but its not real clear if to me if the ICV should be getting current the whole time the car is idling or not (i attached a pge from the FSM) it seems to me thats what the manual says, that the ICV should get about 4-5 volts with the car idling, so does this mean that my idle control module is bad? because its not sending 4-5 volts to my ICV? also hot cold does not seem to make any difference at all in regard to this idle problem
see #3 on attached PDF
thanks
kenny