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BUB1988 · 03-02-2011, 05:10 PM

I have a 1988 Fleetwood Southwind and the house batteries are not charging when on the alternator. It appears that Shore power and Generator do charge the batteries. Voltage jumps to about 12.7 on shore power or generator.
I ran the batteries down below 12v and started the engine and there were no voltage jump. I have a battery isolator with two solonoids that do show battery voltage but when I turn on the key the small connector on either solonoid has no power. I have attached a picture of what the isolator and solonoids look like. Page two is where I think the problem is.

Any help is appreciated.

Gary - K7GLD · 03-02-2011, 05:25 PM

Quote:

Originally Posted by BUB1988

I have a 1988 Fleetwood Southwind and the house batteries are not charging when on the alternator. It appears that Shore power and Generator do charge the batteries. Voltage jumps to about 12.7 on shore power or generator.
I ran the batteries down below 12v and started the engine and there were no voltage jump. I have a battery isolator with two solonoids that do show battery voltage but when I turn on the key the small connector on either solonoid has no power. I have attached a picture of what the isolator and solonoids look like. Page two is where I think the problem is.

Any help is appreciated.

I'd suspect that wire from the short terminal block that you marked as "goes nowhere, lies next to battery" is the ground side for that battery charging function - if I'm right, it will need to be connected to the ground side of the battery for proper charging - but that's only a guess from looking at your pictures and your labeling - dont blame me if you try it and the RV goes up in fllames.

jmerritt · 03-04-2011, 12:50 PM

Your problem is with the wiring of the Isolator Relay. You should have three wires from the relay and they need to be wired as described in this info. Check to see where each of the three wires go and you probably will find your problem. That red wire is probably to the switch for joining chassis and house batteries for emergency starting in the event your chassis battery is low or dead.

Intellitec's Battery Isolator Relay Delay/E offers a low cost, reliable approach to charging multiple batteries.

Unlike diode isolators, this system provides an engine driven alternator with main battery before connecting the auxiliary battery. This allows the use of self-exciting alternators and lets the engine briefly warm up prior to placing the load of a heavily discharged auxiliary battery on the alternator.

The unit is fully encapsulated in a plastic enclosure for mounting in the engine compartment with two screws. It operates in combination with a conventional continuous duty cycle isolator relay that has been used by a number of vehicle manufacturers. There are three (3) wires to connect to the delay unit: one from an ignition switched 12 volt source, a ground and the isolator relay coil.

It operates by sensing the voltage on the main 12 volt system. When this voltage goes above 13.3 volts for approximately 12 seconds, as happens when the engine is running normally (normal alternator output voltage is approximately 14.4 volts), it will close the isolator relay providing charging current to the auxiliary battery. When the ignition switch is turned off, the relay will open immediately.

If the voltage should drop below 12.0 volts for more than two seconds while the engine is running, the relay will drop out. This might happen when the alternator is not able to supply sufficient current to all the loads and charge the auxiliary battery.

When the main battery voltage rises above 13.3 volts again, the relay will again close in about 2 seconds to retry charging the auxiliary battery. The resultant flicker of the
lights will alert the driver of the system overload.

BUB1988 · 03-05-2011, 03:37 PM

Thanks for the responses to the post.
First I did go ahead and connect the cable to the negative side of the battery and nothing BLEW up or caught fire. I don't have the RV here, against code to park in driveway, so I will have to check the relay when I go to the RV maybe tomorrow. Will update the post as soon as I check it out. Again Thanks for the info

BUB1988 · 03-22-2011, 04:41 PM

Thanks for the info on where to buy the isolator relay. Once I receive the part and put it on I will send in the verdict.

BUB1988 · 04-05-2011, 06:49 PM

I installed a Intellitec's Battery Isolator Relay Delay/E that I bought new on ebay for $16.50. That seemed to do the trick because the batteries are charging with the alternator. Thanks to all that spent time answering my post, especially Jmerritt for the info on the relay.

BUB1988 · 04-22-2011, 06:26 PM

I installed the new Intellitec's Battery Isolator Relay Delay/E and all seemd well until we went on a trip. Now whenever the Intellitec's Battery Isolator Relay Delay/E kicks in to charge the house batteries the gauge fuse blows. I can unhook the Intellitec's Battery Isolator Relay Delay/E and the fuse did not

blow. It seems like the fuse blows as the alternator gauge starts to go up around 14 or 15 volts?

melvonnar · 05-19-2011, 01:24 PM

I had a 1988 southwind with the same problem; after mounths and months of trying to fix the problem, I simply used a jumper wire from the positive of the starting battery to the positive of the house batteries. when I was camping without hookups I disconnected the jumper to keep from running the starting battery down. had the motorhome for 15 years.