dukeman7595 Report post Posted October 21, 2011 Hello, I have three new batteries -- one 12-volt and two 6-volt (new) that went dead overnight. I left the circuitbreaker on as I was doing some work after dark, and the next morning they were stone cold dead. I turned off the breaker -- which is located over the door -- and charged the batteries . They appear to be ok. Is this normal, or do I have a short somewhere? NOTE: This is the first time I did not turn the breaker off when finished with the motorhome. The motorhome is a 1992 Southwind gas w/ 85,000 miles, and no I do not have much experience. This is my first coach, purchased two months ago. Any advice would be very helpful. Sincerely, JOE Share this post Link to post Share on other sites
wolfe10 Report post Posted October 21, 2011 Joe, Are the 12 VDC and two 6 VDC batteries the chassis and house batteries respectively? Odd to combine 12 and 6 VDC in the same bank. You either have bad batteries or a pretty heavy draw. Did you check voltage at the batteries? What was it? Brett Share this post Link to post Share on other sites
dukeman7595 Report post Posted October 21, 2011 Hello Brett, Yes, they are in series 12 to 6v, to 6v, Batteries show 13.6 when charged. After recharging they are showing 13.6 at solar panel and holding. These batteries are only 2 months old. Sincerely, JOE Share this post Link to post Share on other sites
wolfe10 Report post Posted October 21, 2011 Joe, Two possibilities: Bad batteries-- even if relatively new. If wet cell batteries, buy a battery hydrometer (under $10) from any auto parts house. Check battery SG (Specific Gravity) with the batteries fully charged. Other possibility is a big load, even when you think everything is off. Use/borrow/rent an ammeter and check the positive battery cable for draw when you think everything is turned off. And, not sure of your answer to my "how are the batteries arranged". Is the 12 VDC the chassis battery and the two 6 VDC wired IN SERIES the house battery bank? Brett Share this post Link to post Share on other sites
hermanmullins Report post Posted October 21, 2011 Joe, Welcome to RVing. The way to check for a draw on your batteries is to disconnect you positive cable from the post. Connect a volt meter between the + post and the + cable. If the meter registers voltage you have a draw. It is a long task but if you see voltage on the meter remove fuses one at a time if you still see voltage replace the fuse and pull the next one. If you remove a fuse and the voltage drops to zero that will be the one that has something drawing down your batteries. As Brett said you can use a hydrometer to check each cell. I have a load tester I got from Northern Tool, about $15.00. I check mine with it. I make sure the batteries a fully charged and check each one by them selves. One of the first fuses to pull would be the radio, it has a small draw for the memory. Good luck. Share this post Link to post Share on other sites
Guest Wayne77590 Report post Posted October 21, 2011 Hello Brett, Yes, they are in series 12 to 6v, to 6v, Batteries show 13.6 when charged. After recharging they are showing 13.6 at solar panel and holding. These batteries are only 2 months old. Sincerely, JOE Joe, That seems weird. The 12 to 6 to 6 in series would give you 24v total. They way you stated it comes to mind this way. 12v negative terminal to ground, 12v positive terminal to 6v negative terminal, 6v positive terminal to other 6v negative terminal. Final 6v positive terminal to hot feed to MH. (-12to ground; +12 to -6 to +6) would be series.) Should be (-12 to ground +12 to chassis system) (-6 to ground +6 to -6 to +6 to house hot) I am thinking that you have the 12v as a chassis battery that starts the engine and a few other odd jobs. The two 6v would be in series producing a 12v output for all the house lights and other odd jobs. You should have an isolation between the 12v and two 6v batteries except for the charging circuit. Most present day voltmeters have a 10 amp capability for measuring amperage. As stated, take the negative lead off on set of batteries and with the meter in AMP mode, and the disconnect switch to the MH in the off position, measure to see if you have any amperage flowing through the circuit. You may see a trace. If you see 1 amp or greater something is just not right. Now turn the disconnect switch on and run the same test. The meter is shunted so you should not damage it if it exceeds 10 amps, but if you have anything above say half an amp, then you have to investigate. Found out what your charging capacity is and see if you can establish a current draw considerably less than that. even with the disconnect switch in the off position you may have residual current draw to some of the electronics to keep the little "button" batteries charged. (Speedometer settings, clocks, am/fm radio memories, etc.) JMHO Share this post Link to post Share on other sites
dukeman7595 Report post Posted October 22, 2011 Gentleman, Thank you for the advice. Sincerely, JOE Share this post Link to post Share on other sites
