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Topic: Alternator not charging house batteries  (Read 207 times) previous topic - next topic
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Alternator not charging house batteries
I’m flummoxed.  I think my E450 alternator is not charging my house batteries when I drive.  I looked in the battery compartment for the manual breaker but not sure what I’m looking for.  I have a 2006 MB.
Solar charging appears fine I think.
Any ideas how to find and check the breaker in the battery compartment.
I am traveling so intermittent cell service
Thanks much
2006 MB
Re: Alternator not charging house batteries
Reply #1 –
Hi Jack;  There is a breaker inside the battery box. At the back and top, it has two red wires on it.  It separates the wire from the engine alternator going to the house battery(ies) plus lead, in case of a short to ground (car accident, etc.)   It may look like this:  If it has a red lever sticking out from the side, you want to push the lever (it rotates) back upright.   RonB
RonB (Bostick) living in San Diego
Original owner of "Bluebelle" a '99 TKB
Re: Alternator not charging house batteries
Reply #2 –
Besides the circuit breaker, the battery isolator diode pack may be burned out, it's located under the hood, driver's side.
It can be tested with a voltmeter to determine if alternator power is passing through it, while the engine is running.
It looks similar to the one shown below.
Cole Hersee 48120 Battery Isolator | ElecDirect

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Alternator not charging house batteries
Reply #3 –
Thanks guys.  Didn’t realize what I was looking at.  Will do some troubleshooting at next stop.  Probably will end up turning everything off and back on.  It always fixes my iPhone.  Cheers
2006 MB
Re: Alternator not charging house batteries
Reply #4 –
With a digital voltmeter you can check any circuit breaker or fuse by measuring the voltage between the two terminals. If there is a voltage higher than 0.1 V, it is open or defective. If no voltage, then measure from one terminal to ground to verify the voltage even reaches the breaker.

Steve
2004 FL
2013 Honda Fit
 
Re: Alternator not charging house batteries
Reply #5 –
Quote from: Steve  - 
With a digital voltmeter you can check any circuit breaker or fuse by measuring the voltage between the two terminals. If there is a voltage higher than 0.1 V, it is open or defective. If no voltage, then measure from one terminal to ground to verify the voltage even reaches the breaker.

Steve


Will do and thanks
2006 MB