AW4 solenoid doesn't "click"

[SurplusFan98]

Hi all,


Just a little context: I'm restoring a 98 2wd XJ with 300k miles that caught fire and burned (because I'm a masochist I guess), and I don't yet know what all is wrong with it.



Currently I'm replacing an AW4 transmission pan, so I pulled one from the yard. While I was at it, I noticed that the solenoids in the doner tranny looked really good, so while I was at it I pulled those too. Now that I have the pan off of my tranny, I can see that my solenoids look.... old and kinda burnt, I guess. So, I went about trying to test the solenoids I pulled. All 3 are showing about 12.8 ohms, which appears to be correct based on what I've read. I then hooked them to the battery to confirm they "click" indicating that they're operating. On the 2 identical solenoids, the ones toward the front, I get a defined click, so I feel confident that these will work...


On the third solenoid from the yard, the one most rearward in the transmission and what I've gathered is actually referred to as the "#2" solenoid, I get no click. This concerned me, so I pulled my #2 and tested it. With it, I get like 38 ohms, and also no click. Pretty sure that means mine is toast, but the fact that I got no click in either case made me question myself. Am I supposed to get a click or not? I would think so, as it seems like opening and closing is the thing's one job. But, I've been wrong before, so I'm asking. I don't want to have to drop this pan again...


If it helps, with the #2 solenoid removed, I get 2 codes: P0700 and P0743


If you guys tell me I need another #2, ok, sell me one for cheap, because O'Reilly wants like $200.



Thanks all!

 

[lawsoncl]

Hi all,


Just a little context: I'm restoring a 98 2wd XJ with 300k miles that caught fire and burned (because I'm a masochist I guess), and I don't yet know what all is wrong with it.



Currently I'm replacing an AW4 transmission pan, so I pulled one from the yard. While I was at it, I noticed that the solenoids in the doner tranny looked really good, so while I was at it I pulled those too. Now that I have the pan off of my tranny, I can see that my solenoids look.... old and kinda burnt, I guess. So, I went about trying to test the solenoids I pulled. All 3 are showing about 12.8 ohms, which appears to be correct based on what I've read. I then hooked them to the battery to confirm they "click" indicating that they're operating. On the 2 identical solenoids, the ones toward the front, I get a defined click, so I feel confident that these will work...


On the third solenoid from the yard, the one most rearward in the transmission and what I've gathered is actually referred to as the "#2" solenoid, I get no click. This concerned me, so I pulled my #2 and tested it. With it, I get like 38 ohms, and also no click. Pretty sure that means mine is toast, but the fact that I got no click in either case made me question myself. Am I supposed to get a click or not? I would think so, as it seems like opening and closing is the thing's one job. But, I've been wrong before, so I'm asking. I don't want to have to drop this pan again...


If it helps, with the #2 solenoid removed, I get 2 codes: P0700 and P0743


If you guys tell me I need another #2, ok, sell me one for cheap, because O'Reilly wants like $200.



Thanks all!

The 38-ohms is definitely bad. The oddball is actually #3 for the torque converter lockup which matches the P0743 code. I don't recall whether it has a very audible click, but I vaguely recall that it operated opposite the other two, opening versus closing on power or vice versa, which might make it sound different. If it's measuring good at 11-15 ohms, you can test with an air hose to see if it's opening/closing.

Screw Oreillys. The AW4 was used in various versions in lots of other vehicles, especially Toyotas and parts are cheap online. The set of 3 solenoids is $55 on Amazon. https://www.amazon.com/aw4-solenoid-kit/s?k=aw4+solenoid+kit

I've never heard of a problem with the cheap replacements failing. The solenoids may look slightly different as they changed a little over the years, but they are still interchangeable. The only issue I've seen is they might require some minor trimming of the mounting tab or plastic around the electrical connector to sit correctly.

 

[SurplusFan98]

If it's measuring good at 11-15 ohms, you can test with an air hose to see if it's opening/closing.

Oh, that's an idea. So shoot air through it powered versus unpowered and see if the result is different. I can do that and report back...

 

[splitz]

Hi all,

If you guys tell me I need another #2, ok, sell me one for cheap, because O'Reilly wants like $200.



Thanks all!

I've got a brand new set I can sell you for $100.

https://shop.advanceautoparts.com/p/atp-at-contr-solenoids-re-5/11237295-P

 

[SurplusFan98]

So I did as you suggested and it appears that the solenoids work, both the yard one and the old one. When not powered air moves through. When powered it doesn't. I guess the mechanism is small enough that its just not audible. Of course I'll end up using the one that is testing in the correct range.


One other question: I saw where a guy on Youtube was recommending to flush/backflush solenoids out with something like carb and choke cleaner anytime that you had to drop the pan. Is that something you guys would recommend?

 

[lawsoncl]

So I did as you suggested and it appears that the solenoids work, both the yard one and the old one. When not powered air moves through. When powered it doesn't. I guess the mechanism is small enough that its just not audible. Of course I'll end up using the one that is testing in the correct range.


One other question: I saw where a guy on Youtube was recommending to flush/backflush solenoids out with something like carb and choke cleaner anytime that you had to drop the pan. Is that something you guys would recommend?

I'd be hesitant to use carb cleaner if there are plastic or rubber components inside. Maybe just some mineral spirits or naptha/seafoam.