Has anyone ever tested their turbo AFM?

[thetremendoustim]

So I tested my turbo AFM according to the FSM and I got the following results:

test #1 yielded my AFM resistance is somewhere around 210-230ohms but a good 40-50ohms away from the recommended 280-400ohms.

 

test #2 sliding the air flap while measuring the resistance yielded a very shaky needle* as i slowly pushed in the flap and slowly let off. Did it do this for anyone else?

 

*The exact "shaky needle" measurements are as follows:

when the contact touches the carbon strip the resistance immediately jumps to 100ohms

when the contact goes to the first "carbon strip exit" (doesn't it look like a fwy exit?) the resistance rises to 200ohms and falls down to 400 as it progresses to the next exit.

when the contact goes to the second "carbon strip exit" the resistance rises to 200ohms and falls down to 400 as it progresses to the next exit, and so on and so forth until the flap hits halfway and then mildly imitates the stated function pattern with slightly higher and higher resistance measurements.

[jeffp]

I tested my AFM, and what I did was to remove the cover and manually connect the ohm meter to the wafer and wiper. You should have a smooth transistion from one part of the wafer to the other. The theory being that as the door opens the resistnce will scale linear throughout the total travel of the resistor sections.

I also disconnected the air temp sensor (the two black wires with the spade lug connectors) and measured the resistance. Then I got a blow dryer and heated the sensor to make sure it started changing resistance. I let it cool and watched the resistance change again. That was a good sensor.

You should not have any jittery readings as you open the flap, and if you hit the next block on the wafer it again should be a smooth transition across that part of the resistor. That is about all there is to it.