2005 Automatic Transmission

[Ferricsteed]

Question on solenoid pack diagnostics. Am I able to supply battery voltage to energize each of the 8 solenoids without a problem? My plan is to supply battery voltage to pin #3 and then ground each of the 8 other pins from each solenoid. Thanks.

 

[08'MustangDude]

So what's the question then? You told us what you did, but then
didn't actually ask anything about the solenoids; only that you were
able to manually activate them. Then told us your plan... So what
is your "Question on solenoid pack diagnostics."?

 

[Ferricsteed]

So what's the question then? You told us what you did, but then
didn't actually ask anything about the solenoids; only that you were
able to manually activate them. Then told us your plan... So what
is your "Question on solenoid pack diagnostics."?

My question is "May I activate each solenoid using 12v battery voltage without burning up the solenoids? My apprehension is the three pressure control solenoids are "current limited" by the PCM to place them in either three positions or use multiple positions modulated by the PCM. They are not "off/on" solenoids like the other 5 are. (The TCC solenoid may be current limited too, not sure.) I just want to mimic the high dollar "transmission testers", do they simply applying full battery voltage with the full current available from a battery which can weld wrenches and screwdrivers or are do they limit the current so the solenoids don't burn up.

 

[08'MustangDude]

IF they are current limited, then use a 9V battery, see if you get any movement
from them. They have INTERNAL resistance, that doesn't mean they are
current limited. They have coils in them. The TCC solenoid coil acceptable resistance,
measured at the harness connected to the solenoid module, is 9 to 16 ohms. The other
solenoids, 16 to 45 ohms. A 9V battery may energize them. However, all you need
to do is use a multiplier and test the resistance on them. SO, say you test the
TCC solenoid, and got 13-14 ohms, well, that is in the 9-16 ohm resistance range.
SAme with the others, if you get readings within 16 to 45, then they're good. You
don't need to apply voltage to test them.

Here's the thing, after the work involved in removing the solenoid pack, and if you suspect that one
of them is bad; then it's not a bad idea to simply buy a newer, updated module for a couple hundred
bucks, and throw it back in. If you guessed wrong, and it was not a solenoid, then you have at least
updated, and bypassed possible near-future problems. You can get solenoid packs on eBay.

 

[Ferricsteed]

Thanks for advice, I followed it. I bought a new solenoid pack and installed it. I was able to both measure resistance and apply battery voltage momentarily to activate each solenoid. Each clicked. I pulled valve body out and pulled each plunger, cleaned and reinstalled. Long story short, the tranny worked for a week but then the problem recurred. The problem codes are 0748 pressure control solenoid A malfunction and 0963 high pressure in A circuit. Tranny then shifts harshly in all gear changes. The next day, I may not have a flashing "o/d off" with the tranny shifting fine. This is an intermittent problem. I suspect faulty wiring. Hopefully I find a bad ground. It is a pain trying to check continuity between the pcm and tranny electrical plug. Will keep you posted.