Battery drain

[Mike J]

After much testing and stripping out. Beginning to wonder if I have the correct battery. Have a Hankook 62 AH 110 mins 540A (Whatever that means. ) Draining about 580 milliamps, with battery control fuse removed draining approx 80milliamps.I realise the radio will contribute to this. No drain through Alternator. Any Ideas, !!!!!!

[wilf]

Clock drawing excessive current?

Boot light not going out?

DItto glovebox light?

[022Dave]

Do you have an alarm / immobiliser fitted?

Dave

[Mike J]

No alarm fitted all bulbs removed. Have a radio EWP and Kenlow electric fan.

[Philip Wardle]

So if we assume the battery is providing about 13 volts and the drain is 580 mA that's about 7.5 watts - appears to be quite significant. Other than progressively removing fuses, the other thought is to borrow a clamp meter, or maybe buy a cheap one. It should serve as a non invasive way to track the drain, starting at the battery and working down the loom.

[StagJonno]

So if we assume the battery is providing about 13 volts and the drain is 580 mA that's about 7.5 watts - appears to be quite significant. Other than progressively removing fuses, the other thought is to borrow a clamp meter, or maybe buy a cheap one. It should serve as a non invasive way to track the drain, starting at the battery and working down the loom.

Clamp meter must be specified for DC current - starting price around £30, eg https://www.amazon.co.uk/Proster-Aut...hlbWF0aWM&th=1

My Stag has a modern radio with permanent supply to maintain memory and a Davies Craig Electric Water Pump. I've not noticed any significant battery drain from these, but ....

[marshman]

When you say you have removed all the bulbs (lamps!) did that include the one in the boot?? a 5W lamp will take close to that current and the boot illumination lamp can stay on with the lid closed and not be seen.

Also have you disconnected the alternator to rule out any faulty diodes in the rectifier/regulator?

The type/model/capacity of the battery will have no effect, drain on the battery is a drain on the battery !

I would disconnect one battery lead and put a 5w sidelamp bulb in series - i.e. connect one side to the battery terminal and the other to the now disconnected battery lead. If there truly is 580mA of current the lamp will illuminate. You can then go around disconnecting things and when you find the problem the lamp will go out.

DC Current clamps are not much good at low current levels and can often give misleading results.

[Mike J]

Thanks all Have disconnected Alternator no change to the loss. tomorrow will take puddle lights and foot lights out . got a hunch maybe cigar lighter. What ever it is its blooming frustrating

[MikeParker]

If all else fails, you could try an infra red camera. 7 watts is enough to heat up an instrument/alternator etc by several degrees. Obviously leave the car for a day or so in a garage out of strong daylight so that it equalises temperature.

[jbuckl]

Thanks all Have disconnected Alternator no change to the loss. tomorrow will take puddle lights and foot lights out . got a hunch maybe cigar lighter. What ever it is its blooming frustrating

Iirc the cigar light is on a non ign controlled live.

often it’s dead though!

could be a culprit .

have had trouble with boot lamp draining in the past on another members car.

[Col70n]

Cigar lighter is permanently live.
I’d be looking at the boot lamp - certainly caused me a few battery problems until I found it….

[Goldstar]

Phone on video in boot. Close boot lid. Watch video and check for darkness.

[Mike J]

Somethigs not right .All fuses out Kenlow disconnected Alternator disconnected. Still showing 85 milli amp loss. Hmm will sleep on it

[wilf]

The stag has circutis which are permanently live - i.e unfused. Alternator is one, but you have discounted that - side/head lights is another - permanent feed to the switch. Ditto up to the ignition switch itself.

[Philip Wardle]

Another thought - the coil of a 12V automotive relay uses this sort of current - are there any wiring mods that have resulted in a relay being energised with the ignition off?