Correct Voltage?

[MarkP]

Appears your isolator is simply being used as a terminal to distribute the wiring. It is not being used. Correct me if I am wrong but both batteries are wired to the same stud, to include the alternator, therefore the batteries are in parallel.

Find a wiring diagram for the isolator you do have and rewire is correctly. It is also possible that the isolator may be bad and needs to be replaced. That could be why it is wired the way it is.

 

[MarkP]

Actually, looking at that picture again, I have to ask, "WTF?"
It looks like all the cables are connected to just one stud. . . .

Looks like Tom nailed it a few minutes earlier. Your previous owner left you a few surprises to work on.

First order of business, get a wiring diagram for that isolator or get a new isolator.

 

[RBBailey]

I'm agreeing with you guys on this, even before posting I just couldn't figure out what the wiring in this truck was supposed to do. Like I said, it looks like a bunch of good equipment thrown together in the wrong way. I think I will have to start over with the wiring layout.

Yes, I did get a good deal on the truck. I won't list it all here, but even without the DVD and 10 speakers, I calculate the parts alone to be more than $20k of accessories. I posted in general under "A New Ride" about a week ago with a list of the stuff I've found on it so far.

Can one of you point me in the direction of a "Plain English" wiring diagram for what I have here, so that I can correct the bad set-up?

 

[ptschram]

Just tie the two positives together and ground the negatives.

You'll be fine.

 

[RBBailey]

The way it is all set up now, it may be easier to actually wire the isolator correctly.

I think it is a Stinger S12023, but I can't find a diagram on it.

The thing I do know is that it is wired incorrectly -- that should be obvious from just looking at the photos. I just need to try to confirm how it is supposed to be wired. I think each battery is supposed to be on one post each, then the alternator is supposed to got to that one small post. This isolator is supposed to be able to charge three batteries, then keep them isolated when the ignition is off. The way it is wired now does not in any way reflect what these things are supposed to do -- and that's me talking, I don't know anything!

 

[RBBailey]

Ok, I *think* I may have figured it out. I may still need to buy new batteries, but I hooked it all up the way I think it is supposed to be -- according to logic -- and I started up the truck: I'm getting 13.4 volts on the aux battery, and there sitting at idle even with aux lights on and all, I'm not getting a battery light on in the dash of the car, so I believe that the alt is now charging both batteries while running. I also confirmed that the voltage on the aux battery goes up and down independent of the main battery.

So... I will know more after letting it sit for awhile.

 

[antichrist]

I think it is a Stinger S12023, but I can't find a diagram on it.

From the part number (and the ratings they come in) I'm betting it's a rebadged Surepower 12023A. Which is for two batteries and not a Schottky diode isolator.
That would explain the low charging voltage also.

The "center" large terminal is for the Alt feed in. The two outer terminals are for the two battery feeds out. The smaller "center" terminal is used to excite the Alt.

For wiring, here are some links.
http://www.surepower.com/pdf/180012n.pdf
http://www.surepower.com/pdf/ebr_int.pdf
http://www.surepower.com/pdf/ebr_iso.pdf

 

[RBBailey]

The "center" large terminal is for the Alt feed in. The two outer terminals are for the two battery feeds out. The smaller "center" terminal is used to excite the Alt.

Thanks, that is how I set it up, and it is working correctly. However, I believe I still need new batteries -- a shame, since I won't be getting Odyssey -- too expensive, and I bet these were ruined simply because of the bad hook up.

I got the main to show 12.8-13.0 while running, and the aux was showing 13.4. I still needed to charge the main in order to start the car. The main does look like it may be a bit older, so I'm wondering if I might get by with buying just a main battery replacement at this time?

 

[antichrist]

Thanks, that is how I set it up, and it is working correctly. However, I believe I still need new batteries -- a shame, since I won't be getting Odyssey -- too expensive, and I bet these were ruined simply because of the bad hook up.

I got the main to show 12.8-13.0 while running, and the aux was showing 13.4. I still needed to charge the main in order to start the car. The main does look like it may be a bit older, so I'm wondering if I might get by with buying just a main battery replacement at this time?

If I were in your shoes I'd take the isolator out of the circuit, disconnect the aux battery and just hook up the main battery per a standard wiring circuit and see how it does. Connect the voltmeter to the main battery pos post. Then replace the main battery with the aux and see how it does. Your batteries might actually be ok and were just flaky because of the weird wiring. You might save enough $ to get a schottky diode isolator. Your main charging voltage is too low.

 

[RBBailey]

At this point...

I got the wiring set up in the only logical way that makes sense with that isolator, so then I looked at the battery voltage and decided to switch the main with the aux because they were both taking a charge while running, but the main was weaker than the aux, so I figured maybe I could get it to run better that way......

Not good enough, but... more than that, the little yellow wire that comes out of the firewall started smoking. I also got an error alarm from my converter that is plugged into the cig lighter. I got a little bit of smoke in the cabin, and I could see where it was coming out in the engine bay.

Anyway, I pulled the plastic off the wire and noticed that between the firewall and and the isolator that wire has two or three splices in it! It comes out of the firewall as two blue and black wires, it is then spliced into one yellow wire that was attached to the isolator. In my tests I confirmed that when I start the car without that wire connected, the voltage stays low, but when I connect it the alternator starts charging.

So, even if I do go to single battery, I still need that wire; and based on the smoke, I bet there is another stupid splice someplace under the dash.

HELP! Does anyone know where that yellow wire (blue and black) go when they get past the firewall?

 

[RBBailey]

Is the excitor wire even part of a single battery set up? Or is that something you wire into it when you put an isolator on?

My theory is that it is not. I'm guessing that the alternator needs that when you put an isolator into the system. I just wired it to a single battery and bypassed the isolator and I'm now getting 13.9-14.2 volts while running on a single battery. I did not use the excitor wire at all. I'm guessing that it has been used in several different dual battery set ups over the years -- this car was a stereo system show car that toured the country -- and that a bunch of teenage gang wannabees did the wiring and kept splicing and kept splicing that wire till it now has so much resistance on it now that when I finally wired the system to use the wire -- poof! -- it goes up in smoke.

HELP!

 

[ptschram]

Pull that damned isolator out of the circuit. If you are really worried about having the batteries separated, except for when the engine is running, there are multiple circuit diagrams available for using a Ford stater solenoid to disconnect the aux battery when the engine is off.

Keep it simple! Whose theorem is it that the simplest (most elegant) solution is the best? Occam? Foucault?

 

[antichrist]

It depends on what your goal is. For me, I off-road alone a lot, mostly in fact, and I want to make sure I don't drain my starter battery when winching, so an isolater works best for me. For some people, a separator meets their needs best.

13.9-14.2 volts at the battery is good.
Need for the exciter wire is dependent on the kind of alternator.

 

[RBBailey]

OK, but the exciter wire is not "stock" is it?

I have bypassed the isolator for now. When I get a chance I will go back in and wire in a new exciter wire -- I would not be surprised if it was stupidly done at the splice to the ignition as well as the other splices along the way -- then I will test this isolator again, or just buy a new one.

I will attempt to start the truck in a few minutes to see if the standard "simple" set up works with these batteries for now.

 

[apg]

I got the main to show 12.8-13.0 while running, and the aux was showing 13.4. I still needed to charge the main in order to start the car. The main does look like it may be a bit older, so I'm wondering if I might get by with buying just a main battery replacement at this time?

Remember what I said: a good battery can be pulled down by a bad one. From your description, it doesn't appear that the isolator is doing anything other than serving as a convenient point to tie in some monster auxilary cables. What is that? 00 gauge?

And as Tom said, 12.8 to 13 volts is too low. I'll wager that one or more of the diodes in the alternator has blown, and that could be the source of your overnight battery drain. Have you tested the alternator with a lamp yet?

I take it that as a "show truck" for a stereo company, this vehicle doesn't have a winch and that this setup only powers some big-ass sound system. If so, ditch that isolator set-up, flog off the stereo components on evil-bay or the nearest ghetto and don't let any more smoke out... "letting the smoke out" is never a good thing, as smoke is what drives British electrical systems. When you let it out, things stop working....

 

[antichrist]

Occasionally NOS Land Rover electrical smoke comes up on ebay.

 

[RBBailey]

Now here is a quick (and cheap) way to determine where this drain is. Disconnect the battery ground lead, and connect a low-wattage bulb between the battery post and the cable. The brighter the bulb, the bigger the drain. (Mind you, there will always be some drain, from things like the clock, alarm system, etc.) Now start disconnecting circuits, like unplug the alternator. When the light dims appreciably, you've found the culprit.

Other than this, how would I be able to test for a leak?

I think it's the exciter wire and a bad, or going bad, isolator. And that the batteries are weak enough now that they feed off each other over night, even through the isolator. But I want to be sure, because as it is now, I can't start the truck in the morning and a new battery will only get ruined if the leak is occurring in some other spot.

 

[antichrist]

The stock D1 alternator uses self-excitation. So really all you need to do for the alternator is to correct the stock wiring.
What I would do is get it wired back to stock, make sure it's charging the battery ok, that the battery is holding it's charge, and then go from there if all is ok.

 

[RBBailey]

I have it back to stock, but with both batteries. I don't think it is holding a charge when sitting. The alternator does allow for 14+ volts, and 13.5 or higher even with all 8 PIAA lights turned on at idle.

I think it is working correctly, but that I need new batteries. I'm just needing to be sure that if I buy a new battery, that I won't ruin it also due to a leak that I am not detecting.

I suppose if I disconnect the batteries over night and they don't take the same drop that they do when connected, I'll have my answer. Then I'll just have to hunt the leak down. But I am highly suspicious of the isolator, so I would start from there.

 

[apg]

Other than this, how would I be able to test for a leak?

This is the cheapest, easiest way to detect a drain in the system. I spent the grand sum of $2.79 at RatShack for a bulb and bulb holder. Add in two bits of wire and two alligator clips and Robert's yer paternal sibling.

Now a variation on the theme is to substitute a buzzer for the light, 'cause sometimes you might be under the dash pulling fuses and can't see the light if the leads are short. A buzzer is too annoying for me....

You'll be able to find out in seconds if the alternator has bad diodes.... Connect the lamp in series between the negative post and the ground cable. If the light goes out (or dims significantly) you've found the problem...well, *one* of the problems.... Of course, if the light *burns* out like a flash bulb, well, you've got one hell of a current drain.... A lower wattage bulb will light/detect a small drain, something that might not illuminate a higher-wattage bulb.

BTW, while you are doing this, remove the second battery from the equation entirely....