Electical fault? dead battery?

[GICarey]

OK, it's back on charge.

For what it's worth, some figures:

Code: Select all

Time     Leisure Battery      Standard Battery       Comments
18:15      12.89v                 13.00v               LB had been off charge a coupla hours
                                                          SB had just come off charge
                                                          (having risen from 6.8v in 60-90 mins)
19:15      12.88v                 12.71v               Both off charge
20:15      12.87v                 12.69v               Both off charge
20:16                             12.45v               Whilst powering a standard Bongo headlamp bulb
                                                           Voltage dropping by .01v every ~30-45 seconds

SB is now back on charge, and I'll look in on it again in 48 hours!

Gav.

[GICarey]

Hello,

OK, so having had 50+ hours of charging, at been "at rest" overnight, the starter battery had settled to a voltage of 12.85v.

Rolled the batteries out to the car, popped them both in and connected up the earths. Both appear to have a good earth connection (haven't tested the engine earth yet, as still need to find it).

Set the multimeter into 10A ammeter mode, red wire to +ve terminal of the battery, black wire to the various wires which go off to the car. Drain across the connection when the car was all off was 0.01 and 0.02 depending on which wire I tested (thick wire terminated in a bar going to the fuse box directly on the terminal, and two wires with "rings" on).

Connected the split-charge relay kit onto the LB side, and then similarly, between +ve terminal and the wire which runs through the relay. Again, a 0.02 amp drain. Waited 20 or 30 seconds, didn't hear the relay trip, and current didn't rise.

Resistance across this seems high, setting multimeter to 2000k ohms setting I get -983 showing when red wire is on the SB side and black wire on the LB side.

Back over to the LB side, current drain from the LB into the split-charge wiring is again that little 0.02a, and when I switch on a small light inside the car (boot light), this rises to about 0.7a


So far, so normal...


Connected everything up (barring the split charge wire on the SB side), tightened it all, and started the Bongo up, leaped into life as eager as ever.

Voltage across the Starter battery rose to about 14.3v, so it would appear the alternator is working normally. Voltage across the LB remained at about 12.8v

Connecting up the LB to the SB side, vis split charger, and, after about 5 seconds, click, the relay opens, and the voltage across the LB rises to 14.3v also. Disconnect it, and about 5 seconds later, click off it goes.


Into resistance mode on the multi-meter, when connected, as the relay opens, resistance drops to 220 ohms (showing 220 on the 2000 ohm setting). when disconnected, goes high (showing -980 on the 2000k ohm setting).


Back into 10a ammeter mode, and use the multimeter, to connect the split-charge relay to the starter battery. Spikes up to about 8a, then drops slowly down towards 3a

Shutting the car off, the SB is showing 13.28v and and the LB 12.82v (confirmed everything switched off inside!)

So, continues to look normal then...


So then, I've left it with the SB and LB connected up as normal, but with the split charge relay kit disconnected from the SB side, multimeter shows no connected between the two +ve terminals, as expected.


Think we'll use the corsa when we go out to Cambridge today, so it can sit all wired up like that overnight, and through tomorrow, and i'll grab the multimeter tomorrow and check out the state of the two batteries. Hoping to use the Bongo for a trip to London at the weekend, so assuming al voltages remain normal, the split charge will stay disconnected until after that, if all good, i'll reconnect it and continue to monitor.


So - good news, she's got electricity and is going again. Bad news, I've no idea why she went flat in the first place!


If there's any further advice on things to check, glad to hear them!

Thanks,

Gav.

Oh = PS: thought I might check the earth from the engine side; any one tell me where this is?

[g8dhe]

OK, all sounds good at present then! It might perhaps just have been a forgotten turn off, maybe a light and the radio going possibly from different batteries that caused the problem. It sounds OK at the moment so other than repeating the check after the weekend and then keeping an eye out for any possible problems in the next week or two.

I'll probably not have much of a data connection again for a few days - just passing thru Bodmin enroute Dartmoor so I'll keep my fingers crossed for you

[GICarey]

Thanks Geoff,

Yeah - that's what I'm thinking, although concerns are:

* Internal lights, stero, cig lighters (originals and additions), and 240v inverter - all supposed to be from LB only.
* Possible drains on the SB ought only really to be engine, immobiliser, door locks & closer and outside lights. The stuff you shouldn't be able to forget easily.

I shall cross my fingers & hope I was just idiot enough to leave lights on and not notice.

Enjoy yourself down there in the south west, it's a common haunt of mine (the misses is from Penzance so we run the Hertfordshire --> Cornwall route fairly regularly in the Bongo).

Gav.

[g8dhe]

Ah well it looks like we have a reasonable GPRS connection from Dartmoor so will be able to continue looking at the forum!

Talking about what's on the L/B and what's on the S/B check how the radio has been wired, as that has two feeds, one from Fuse 1, which also has the Cigar lighters and also a feed from Fuse 8 which is the main power via the ignition, however some radios will take power from either if only one power source is connected, so its possible that if one battery goes flat then the radio will switch over to the other (not many do this but a few sets do) and that will then flatten the second battery, however for this to have happened you would have had to have left the Ignition ON and the radio as well....

[GICarey]

Hmm, interesting call, I shall examine the stereo wiring when I get a moment.

Following Wednesday AMs playing, a check Thursday night gave:

Starter Battery Voltage: 12.8v
Leisure Battery Voltage: 12.58v (though 2 internal bulbs were running as door & boot open)

That's down from:

SB is showing 13.28v and and the LB 12.82v - after Wed AMs playing, starting & running the engine, etc, and...
...a voltage of 12.85v on the SB and 12.7v on the leisure battery - before Wed AMs playing around.

So, doesn't appear much of a drop in the short term.

I'll be checking them again later today (Friday), and then using the Bongo for 2 50 or so mile trips over the weekend. Will take the charger etc "just incase"

Thanks,

Gav.