Our frequent dead starter battery problem seems like something we should have addressed right away, with the apparent worsening over the last month emphasizing the point.  Believe me, we have tried: two different mechanics took a look and reported that since the symptoms were so inconsistent it was near impossible to trouble shoot down to the bad component.  After our battery troubles going to Carmel Valley, however, I assumed that the problem had worsened to the point of consistency.  Thus our decision to forgo Yosemite and head straight back to the Coach Maintenance Company.  Imagine our surprise when, after thee hours of driving, we pulled over at Wal-Mart with the intention of recharging the certain-to-be-low batteries with our Honda generator while we bought groceries and ate lunch, only to find this:

What the?

That’s right, fully charged,100% ready starter batteries.  This is doubly surprising: not only were they not depleted after a drive that, based on our Carmel Valley experience, should have shown them well below half, but for the past month I have not seen the batteries above 67% even after a full night of trickle charging!  I was not sure if that 67% max charge was a result of using a smallish 12V charger on these big bus batteries or if it had something to do with the way they are wired in series, but I was becoming concerned that in addition to whatever problem I had with the alternator and associated charging system, I might also have to replace the less-than-one-year-old batteries themselves.

Big ole bus batteries

So this is one of those good news bad news situations: the batteries charged up while driving, allowing us a smooth run to the mechanic, but now we are right back to the inconsistent symptoms problem that prevented repair the last two times.  Adding to the stress, Ted has not been able to look at our bus since we arrived two days ago.  He has moved us ahead of another bus job to the “on deck” position, but he encountered significant problems with the job in front of us, which he originally expected to be complete yesterday.

Wiring panel beside the driver seat. Pretty simple, right?

There has been one shining spot of progress, though.  During his breaks we have talked extensively about the bus, with special emphasis on indicators and warning symptoms.  Some of you might recall my complaints about all the unlabeled warning lights and switches we inherited from the previous owner, most of which we have figured out through trial and error.  One indicator has been particularly difficult to sort out.  A little red light below the speedometer has, as long as we can remember, sporadically illuminated during drives.  During the course of the last few months it has become more frequently lit, to the point that it has been solid red the last week or so.

Unlabeled indicator lights: Two greens are turn signals, Blue is high beam head lights, Top left red is low air pressure, the other three reds are unknown…

Originally I suspected it had something to do with our long standing transmission problems.  Once those were fixed I thought it might be related to our unusually low oil pressure reading that Ted pointed out last week.  But after a conversation yesterday with Ted, I learned that one of the core indicator lights on the original driver panel was a generator (alternator) circuit failure light, and it hit me.  Though the light has been near solidly illuminated the last few weeks, the exception was our run from Monterey to Williams the day before yesterday: the light was off pretty much the entire trip, which was surprising and rare enough that I mentioned it to Rosemarie.  The same run where the battery system charged.  Doh!  Finally we have not only the answer to an indicator light mystery, but a clear way of knowing when to expect a dead battery after driving.  Progress!