26 replies to this topic

[Graeme Lambert]

Right, this is on the Saab rather than the VX, but hopefully a few of you will be able to answer anyway. I'll keep it short, but when the car is 'off' what would you expect a normal/acceptable battery drain to be? Thing keeps going flat, despite a new massive battery. Tested by RAC (don't actually own a multimeter) and was showing 0.28amp as a drain. Thoughts appreciated. G

[peteslag]

Wow, that is 280 milliamps, FAR too high. You should see no more than about 30 milliamps (0.03 amps). The way to fault find is have a multimeter connected and pull each fuse one at a time. When the current flow drops to a normal amount you have found the guilty circuit.

[Graeme Lambert]

Thanks Pete, That's kind of what I thought. I have a feeling I'm going to be having a discussion with the RAC in the morning then G

[slindborg]

How fast is it going flat? 280mA is high but you should still get a Long while from that.

[Graeme Lambert]

How fast is it going flat? 280mA is high but you should still get a Long while from that.

It's a 3rd/4th car when you take VX and company cars into account so in effect rarely used.

Battery was new in Oct, and I went for a slightly oversized one (3.0V6 model rather than the one for 2.3turbo) due to the above fact, hoping it might help. Have had to boost it with CTEK regularly (not constantly as its on drive). At weekend I went to try car and not enough power for central locking, turned key in ignition and it as 100% completely flat - no flickering lights on dash, no click no nothing.

Put car on CTEK over whole weekend - around 20hrs or so in total - and it made zero difference. Didn't even revive it one iota. Still no flickers of dahs lights or anything, it was like I hadn't turned it on at the plug (I had - I checked).

Conversely VX hadn't been started since 2012 and with 4-6hrs on CTEK I had enough charge on battery to turn it over for 30 secs or so without ignition to get oil flowing then fire it up properly after that.

I'm happy to accept that the battery in the Saab is now toast, but RAC's offer to fit another (at £120+ versus the £70 it cost for my VARTA one of the same size) is to me just a bandaid for what is another underlying problem - ie that battery drain. I told them as much when I spoke to them on phone last night, when booking call out, but it doesn't seem like they've listened.

What I need to know really is whether the guy was bullshitting me that a drain of 0.28amps (on his digital meter I saw it fluctuating between 0.22 and 0.38 amp) is normal, or whether in fact this is a problem. He ws keen to sell me a battery and quite dismissive that I had a battery drain. His tune changed when he enquired about the Infiniti on the drive and asked if it was a company car, at which point I told him what I did, suddenly making his excuses and leaving...

At this rate I'm just going to pay someone on shiply to transport it to my specialist in Nottingham and get them to sort it (and do some other jobs that need doing too).

G

[Boombang]

The CTEK chargers need a volt or two before they will charge. You can parallel your battery onto a running car to give it some initial charge, then give the CTEK a go. Might be lucky, although this doesn't help with the drain.

[slindborg]

I've had to charge batteries before leaving a CTEK to maintain the car. I'll have a little measure on some of the worst offenders for battery drain and get back to you

[ghand]

As above some chargers will not turn on if they do not see 2v ish If your battery had been at zero with the drain on your knackered. If you disconnect one side of the battery and leave it an hour the volts will (usually) come back up a few volts naturally without a charge, don't ask me why then the charger will kick in. If not its the jump leads.

[Pidgeon]

1, Just because it's flat it'snot 'toast'. Give it a good charge with a charger, not a conditioner. 2, The RAC's role is to get you home, not diagnose problems. I'm amazed people still patronise them.

[ghand]

1, Just because it's flat it'snot 'toast'. Give it a good charge with a charger, not a conditioner.

2, The RAC's role is to get you home, not diagnose problems. I'm amazed people still patronise them.

Yes the battery is probably perfectly ok just not been charged with this modern crap.

What's needed is a good old fashioned lets whap some current in charger One big transformer and one big rectifier and no frigging electronics, job done.

[Mangham54]

Also worth considering one of the plug in solar panel chargers that Maplins sell for around £20. I doubt it would 'solve' the drop, but will slow it - until you either get the underlying problem solved or will just help keep the bugger topped up afterwards.

[peteslag]

Did the RAC guy do this: 1, disconnect one of the battery terminals 2, connect his meter between the disconnected lead and the battery terminal If he did this and you saw any thing more than 0.03 of an amp on the meter, you have a current drain. If he did any thing else he is bullshitting you. It is very easy to find the cause so your garage should be able to trace it no problem. If there is a drain you will need to have it fixed. As for the battery being toast, COMPLETE AND UTTER BOLLO@KS!!!!

[slindborg]

Did the RAC guy do this:

1, disconnect one of the battery terminals
2, connect his meter between the disconnected lead and the battery terminal

If he did this and you saw any thing more than 0.03 of an amp on the meter, you have a current drain. If he did any thing else he is bullshitting you. It is very easy to find the cause so your garage should be able to trace it no problem. If there is a drain you will need to have it fixed.

As for the battery being toast, COMPLETE AND UTTER BOLLO@KS!!!!

he may have had a clamp meter.... Thats how we do it to check the sleep current of our stuff in vehicles.

[ghand]

Clamp meter tells you if you have current drain but if you go across all the fuses one at a time with a meter set to mV you can see which circuit is giving the drain. Just dab across the fuse,they have little pins you can get on, if no current is flowing you get no mV if it is drawing current you will see a small mV reading across the fuse.Then just look on the box lid or book to see what circuit it is. Obviously some draw a small current all the time for memory back up and so on. but it is a good quick way to find a circuit thats not supposed to be drawing current without disconnecting stuff or pulling fuses .

Edited by ghand, 10 April 2013 - 03:26 PM.

[Zoobeef]

I have one of these. Not used it but would be handy in this situation. http://pages.ebay.co...id=400433639239

[ghand]

Looks good and would work well.Only problem on the complex sh*t they fit nowadays some stuff shuts down after time and when you pull a fuse and re fit in "wakes up " again but would work for most stuff

[slindborg]

yep, need to leave a car atleast 30 mins to be sure its gone to sleep

[Zoobeef]

Should I play it soft music too?

[Boombang]

Mug of warm petrol?

[ghand]

Should I play it soft music too?

Thats the beauty of an old VX it goes straight to sleep when you take the key out

Modern cars have all sorts going on for ages after you have gone to bed