How do I test the Trans Solenoids

[Hylander]

OK:
I have checked at th Connector under the Hood, all is the same at
that point.
The Black wire, Pin #1 is supose to be the ground but is not acting grounded. I traced that black wire and the white/brown stipe wire to a white plug on the side of the Trans, at that plug the black wire is still not showing it is a ground. The 3 Solenoid wires are in a seperate Loom that goes behind the TC shift bracket and I can not see where it goes from there.
Should I pull the bracket to check the wires behind it, or open up the Trans Pan and test the Solenoids themselves ?
I just don't understand that all 3 Solenoids would show Zero Resistance and the Black ground wire shows nothing

 

[orange]

Don't rip it all apart yet.

Seems like something is NOT right in the testing.

The meter is set wrong or wrong wires or something. You should be reading to chassis ground on the 'ground wire', also it would be very strange to have all three solenoids dead shorted.

-Need some part that is known to be - say between 10-50 ohms to see if test metering is ok. (Another Jeep?) (FSM- other sensors.?) (Radio Shack?)

-Need to verify Correct Connector Pin Numbers are being tested.

Do some research about this.

Good Luck,
Orange

 

[B.RAIDER]

Check your grounds by going from the battery ground to the chassis somewhere. I forget, it should be less than 1 ohm....somebody else could verify this number.

 

[Hylander]

OK:
I must be using the OHM Meter wrong.
I just tested two more Cherokees and get the same Results,
No Resistance.
Thats 3 Cherokees and and 9 Solenoids, they can't all be bad, I even pulled 3 Solenoinds from a Trans and tested them with Zero Resisitance,
so I must be doing it wrong or my OHM Meter does not read that small of OHMs.

 

[B.RAIDER]

or my OHM Meter does not read that small of OHMs.

That was my problem when I was searching for my fix.
I have two DMM...even the $3.99 one from HF read the same as my good one.

 

[kastein]

What scale do you have the meter on? You should be using the lowest ohms scale - probably 200 ohms or 100 ohms depending on who made your meter. Also, make sure you zero it before using it else your numbers may be off - touch the probes together and then turn the adjust knob or screw till the meter points at zero.

EDIT: also, do you have the probes in the right holes in the meter? Most meters have four holes, COM, V/ohm, milliamps, and a high current setting. You should have your black probe in COM and your red probe in V/ohm.

 

[Hylander]

Alrighty;
Went to Sears and my Wife bought me a new Craftsman DMM
Retested everything and it seems that Tans Solenoid A is bad.
Solenoid B and C (Lockup) tested 12.2
and Solenoid A tested 18.2
This is with the engine and trans cold, I will also retest them after the engine & trans have warmed to operating temps.

 

[orange]

Good Wife! - Keeper!

Recheck as near as you can to the trans, to try to eliminate the wiring/connectors before pulling the pan.

check solenoid before pulling it to verify wiring is good prior to changing.

Recheck all 3 solenoids prior to buttoning up.

- Dex/Mercon 3 -

Set ATF level with Jeep FULLY warmed up - at least 20 minutes drive - and with Jeep as level as you can get it.

Good Luck, Happy Trails....
Orange

 

[Hylander]

After warm up:
Solenoid A was 2.980 to 3.000
Solenoid B,C where 14.9 to 15.1
I checked at the last wiring connector under the hood

 

[kastein]

Sounds like solenoid A is definitely toast then. 3 ohms is way low, that thing will pull nearly 5 amps at normal running engine voltage. And the fact that it's too high resistance when cold makes me even more suspicious. The driver chips used in the 97+ TCU (Sanken SI-5154s) are only rated for 2.5 amps absolute max, and will go into overcurrent protection mode (and *should* throw a CEL with a related transmission code, if the TCU firmware was well written) at 2.6 amps.

 

[lawsoncl]

Here's a link for sourcing new solenoids.
http://www.naxja.org/forum/showthread.php?t=996259&highlight=aw4+solenoid+source