2007 SSV not charging, but good alternator and battery

[Toonces]

It seems like a decent scan tool would show the commanded generator duty cycle, and maybe the value of the "turn on" signal.

I'd guess you're right, but all I have for GM is a generic DTC reader. I typically con the American car shop next door to mine into scanning the only newer GM I've had to date, but this Tahoe is currently getting a lower ball joint replacement at my house (don't ask), so I was hoping to find an independent source to bench test it so I could be more definitive in returning to the alternator rebuilder.

A scan tool is in the plans but I do a lot of research on this stuff and it'd be nice to resolve this specific issue sooner than later.

Thanks for the response & the link!

 

[Fless]

If the alternators test okay, what's Plan B? The second link I sent has some testing info regarding the voltage measurements for alternator control. Keep that one in your back pocket in case you need it later on.

 

[Toonces]

If the alternators test okay, what's Plan B? The second link I sent has some testing info regarding the voltage measurements for alternator control. Keep that one in your back pocket in case you need it later on.

I'd eventually intended to get a proper scan tool for the truck anyway, so that might speed up the process. Do you have any suggestions as to what threads or sites I should look at to get a good sense of the pros and cons of the various options? Looks like one is needed to properly follow the diagnostic procedure outline in your second link.

 

[Toonces]

@j91z28d1 wins the diagnostician of the week award, along with my huge thanks. Of the six tests performed by O'Reilly's bench tester, this alternator failed all but the current leakage test. So I'll be returning to the rebuilder to um, share my disappointment with them. I'll let you guys know what happens.​

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In the meantime, still need to find the best bang-for-the buck scan tool for that truck.

 

[Fless]

I have an Autel that will do just about anything any other decent fairly inexpensive bidirectional scanner will do, plus it will program (initialize) Autel TPMS sensors, as well as re-set any brand TPMS sensor positions through the DLC port. MaxiPro MP808S-TS. Comes with one year of free updates; the updates after that are for newer years, so I haven't bothered to pay for that. Autel has quite a few different models, but if you look at them be sure you check the Android version. I was seeing some low version numbers on a few models when I bought mine a couple of years ago.

There are many people who rate them, especially on YouTube. Eric O at South Main Auto; Ivan at Pine Hollow Auto Diagnostics does has some comparison videos and you can purchase some in his Amazon store. But there are many others that will review and rate them.