Okay, there's a tool this is a General Motors special tool but you can do a similar thing
with just about anybody's solenoid where the solenoids themselves are removable now there
are some solenoid packs where the entire every single solenoid is in one package and you've got
to change the entire thing you're going to have a hard time test in that but this has as you can see
a bunch of air nipples connected to it and then on the back side it has passages where we can connect
a solenoid to it okay so I've got one solenoid connected there this solenoid has an electrical
connection it's just two wires and then alligator clips to connect it to a battery the power supply
which I forgot to get out so let me get my jumper box out of here when you guys use a jumper box on
a stainless steel top bench with cable need to have some insulation somewhere maybe grab
some fender covers or something so that we don't short something else but I'm going to connect
okay so let me tip this to where you can see it
I'm just connecting power to the jumper box and listen to the click
that's the on-off clicking that I'm talking about now this is a normally
open solenoid so it should blow air through it always this is going to be pretty noisy
that's a bad solenoid it's leaking - so should it eliminate all yes all hair pressure so let me
stick one end let me stick another one in I've got four different solenoids here okay uh plug
the air in again that's what it should do and when it shuts off that's when that valve and the
valve body would a pressure build up and move it there's another one let's see if this one clicks
hey it clicks well these are different size holes for different solenoids you
want to make sure that they click before you hit the air tool right this one clicks
oh good and one last one see if it clicks no clicking so we've got one that clicked but didn't
seal we have two that clicked and sealed the air pressure and then one that doesn't click at all
and if we have the air hooked to it just always be going through it now these are all normally open
solenoids there are some that are normally closed I've got an Allison Transmission valve body right
here so here are those two pulse width modulated solenoids that told you about the color salt on
a and B that actually do the shifting then we have three separate shift valves to position
the shift knob so it's ready to shift we have a torque converter clutch solenoid and then we
have another solenoid to turn line pressure down in the islands when we get a quieter operation
all of these solenoids that look the same that was different all of these are on-off solenoids
it's these great big ones are the pulse width modulated ones so they're going to have different
resistances let me just grab a multimeter real quick you're going to have to do the same thing
we're just going to go to ohms and then you're just going to do a resistance test of
each solenoid so there's 10.9 ohms 22 ohms and these great big ones remember it said they're
pretty low resistance 5.7 ohms. So as long as there is this is different between the
first this one notice it's a different looking solenoid this is actually pulse width
modulated also for the torque converter clutch slowly instead of just torque converter clutch solenoid
just on or off it's a miniature pulse-width modulated solenoid