rvnit4now Report post Posted April 12, 2019 Haven't been to rv in about 9 months. House batteries were dead. Replaced house batteries (4) and when i energize the aux battery cutoff switch the lights on the monitor panel come on and then immediately go out. I suspect the battery cut off relay is bad. Any thoughts Share this post Link to post Share on other sites
wildebill308 Report post Posted April 12, 2019 What is your voltage on the cable coming off the house batteries? Bill Share this post Link to post Share on other sites
rvnit4now Report post Posted April 14, 2019 12.5Vdc Share this post Link to post Share on other sites
manholt Report post Posted April 14, 2019 Coach make, model, year, would be helpful? Also the 4 house batteries you replaced, 6v or 12v? Share this post Link to post Share on other sites
wildebill308 Report post Posted April 14, 2019 On 4/12/2019 at 8:24 AM, rvnit4now said: I suspect the battery cut off relay is bad. Any thoughts Well the next test is checking the battery side of the relay, do you have 12.5 there? Then the output side with the relay on/energised, do you have 12.5? Bill Share this post Link to post Share on other sites
jleamont Report post Posted April 14, 2019 rvin4now, with the salesman switch ON, make sure you have the same voltage on both large lugs. Since you know you have 12.5 at the house batteries, you should see the same on both lugs. Share this post Link to post Share on other sites
rvnit4now Report post Posted April 16, 2019 2006 Fleetwood Excursion 39l, Caterpillar 359hp Allisson transmission Share this post Link to post Share on other sites
Donco234 Report post Posted April 16, 2019 My motorhome will "mimic" this problem with the battery cut off - cut off. There are a couple of small "keep alive circuits" for radio memories etc. that bypass the cut off. These circuits can bleed a little power onto the normal circuits which is enough to illuminate low current devices momentarily. Also some solar battery maintenance panels (the small ones) can cause this. It sounds like to me that your main disconnect is not making connection. My coach has both a "salesman type switch" disconnect AND a manual disconnect switch near the batteries. I would start there Share this post Link to post Share on other sites
