I've got a 5.4 L gas 2001. Uses a group 65 battery. I had one that leaked; it was pretty old so just replaced it a few weeks ago with a nice Odyssey. Put it in, did a few local trips over those weeks; everything seemed OK.

I just started a trip north from Oakland. Again, started OK, didn't notice voltage meter though. Got gas at about 30 mi; OK. Stopped at rest stop at about 65 mi; OK.

Then at about 140 mi I stopped for a late lunch; maybe 45 min. Came out; no start. Not even a solenoid click. The alarm goes nuts (which it does when battery fails) so dealt with that. Got my multimeter on the battery and it seemed to go from 12.8 to about 4.8. Then back again. I'd try to start; nothing. Aargh.

Walked to WalMart. Bought new battery and put it in. Drove home. Put multimeter on the cig plug, and OBD scanner in. OBD would fluctuate from 13.5 to 14; multimeter showed a pretty consistent 13.92, or a bit higher if I turned off lights. Seems high to me, but it shouldn't have broiled a new battery. Not sure exactly where the OBD gets voltage either.

I get home, turn off van in street. Go to start it five minutes later, nothing. Multimeter shows 12.8 though. Then I notice negative terminal is loose. Now I did, mind you, slap that battery from WalMart in pretty quick, but even at home I have trouble tightening on the neg terminal (past experience has taught me sometimes they don't fit as well from battery to battery; wish I had side terminals).

That got me wondering if it was loose on the Odyssey as well, but I don't see how that could explain a 5v reading on the multimeter. Seems it would be 12ish or nothing. When I got home it was back to 12.8; I put a light load on it to see if it will handle that for a while.

Any idea what's going on? Did I just get a dud Odyssey, and then an installer error on the loose terminal? could a loose terminal explain the Odyssey problem?

Rob

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2001 Ford E250 Sportsmobile with Salem-Kroger 4x4 conversion

14 is normal and wouldn't hurt a battery. I bet your loose post was the problem. That or your alternator is going bad. Did you check the connections at alternator and frame for looseness or corrosion? Your symptoms are not weird to me. I've had charging systems do very strange things when something wasn't right, and if it's not something easy like a loose terminal (which I think yours probably was) it is usually an alternator going bad. Good luck!

I doubt it's the alternator; I can't reach all the connections but the fact it never fell below 13.5v over hours of driving, including the last stint where the battery post was either unattached or barely attached, leads me to think it's OK. House batteries were fully charged as well.

I was also wondering if I had a voltage regulator issue. But from my experience with motorcycles I'd think I'd see swings above 14.25 or more, or less than 12 if it was wonky. The dash components have a separate regulator (at least I think vans do) which explains why the measured voltage at the cig lighter is more constant at 13.95.

I'm gonna see about getting the Odyssey tested before I return it.

Rob

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2001 Ford E250 Sportsmobile with Salem-Kroger 4x4 conversion

I had that problem with a side post battery...just a poor neutral connection. But I never tested with a voltmeter. I know if you don't test on the lugs themselves you might get a false reading and the probe might have to get past corrosion to make a good contact on the battery lugs themselves. One thing I hate about side lugs is sometimes they're difficult to get a good reading off them unless you pull the leads. Wiggle them and sometimes the vehicle starts up.

I'm not saying you don't have a bad new battery and although I've never seen that I would think it's possible. Those have a good warranty so I'd take it back, tell them its intermittent and get a new one. Too bad you had to pop for a new battery. You must not have a separator or at least a separator set up to Jump start.

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2006 Ford 6.0PSD EB-50/E-PH SMB 4X4 Rock Crawler Trailer

Sportsmobile 4X4 Adventures..........On and off road adventures

Probably the posts. I had a leak, as I mentioned, in a previous battery and I think it both lub'ed and added some gunk to the clamps, which got onto the posts. Frankly I’m not sure if I always had the probes directly on the posts, so my reading might have been wrong.

After a night of sitting, the battery was at 12.8. Tried to start van via it and jumper cables; turns out that doesn't work. Aaargh. So before putting it back in took it to an O'Reilly and had them test it; turns out OK. I just don't figure it would show 100% on that and be bad. In any case, picked up a cheap battery tester at HF, and it gave same results. These are, I assume, the AC conductance type testers that measure internal resistance to surmise the state of the battery health. I would think that this would show if the battery were a gross fail; mine had low resistance, <2 ohms. It would tell me if it has it's full capacity, but that's not the problem I probably have to worry about.

So in went the Odyssey; starts engine fine. Alternator pushing out 14.3 volts just after start; good voltage going to house batteries as well. I'll watch the connectors, but I hope I fixed it.

Thanks for the suggestions.

Rob

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2001 Ford E250 Sportsmobile with Salem-Kroger 4x4 conversion