Solenoid and wiring pass, still throws code

[KKlausse]

I've got a '21 T770 that throws M1732 after warm up. The solenoid pulls 1.5amps and reads 8.6ohms and the wiring checks out clean with tight connections. Could this be a grounding issue at the controller or something internal to the spool valve?

 

[Bright-Ad1444]

That amp draw and ohm reading sound close, but some manuals list 9.8 ohms as ideal. It could be a grounding issue at the controller or even a weak coil starting to fail under heat. Have you tried swapping in a known good solenoid or checking voltage at the coil when the code pops? Could be that cold weather's playing a role too

 

[KKlausse]

The 9.8ohm spec is helpful information. My service information must list something different. The problem only shows up after the machine is warm. The next time the code appears, I will check the voltage at the coil itself.

 

[Mobile-Cycle-100]

That amp draw and ohm reading sound close, but some manuals list 9.8 ohms as ideal. It could be a grounding issue at the controller or even a weak coil starting to fail under heat. Have you tried swapping in a known good solenoid or checking voltage at the coil when the code pops? Could be that cold weather's playing a role too

Interesting! I haven't tried checking voltage at the coil yet, might do that next. Could cold temps really cause a weak coil to act up more?

 

[89Palpitations]

The 9.8ohm spec is helpful information. My service information must list something different. The problem only shows up after the machine is warm. The next time the code appears, I will check the voltage at the coil itself.

Just curiousm when the machine warms up, have you noticed any difference in performance before the code pops up? Also, does your service info list specs based on temperature? Maybe there's a thermal tolerance difference you can dig into

 

[KKlausse]

@Mobile-Cycle-100 @89Palpitations temperature extremes can affect coils but heat is the more common factor for failure. My issue was happening only when the machine was hot.
I finally had an opportunity to test the machine until it faulted again. As suggested, I checked voltage directly at the coil connector when the code appeared and it was dropping significantly. A new solenoid is now on order and I expect it will resolve the problem.