Battery Drain Overnight

[deano266]

Hi guys. I have installed a Premier loom into my kit and the battery will be drained to about 10 volts overnight if left from about 6pm.

 

I have found that the headlights and fog lights along with the indicators all work without the ignition being on and will even work without a key.

 

Is this normal?

[richyb66]

No not normal. I've got a Premier loom and the indicators need the ignition to be on and I'm pretty sure the headlamps and fog lamp do as well but I'd need to check to be sure.

 

Regardless of this, if the battery is draining overnight (and it's known to be a good battery) then you need to start looking for faults. First thing to look for would be things that might be on but aren't obvious like dash light or power to the ignition.

 

Next step would be to pull the fuses individually and use an ammeter across the fuse terminals to determine which fuse circuit has current through it which should at least narrow things down a bit.

[IanS]

Faulty alternator can be a cause.

When running it charges the battery but discharges it when stopped. A quick check is to feel the alternator before starting the car, if it is warm then this is almost certainly your problem.

[deano266]

Had a new alternator on it and done that already so have ruled that out

[fry61]

Remove one battery terminal & remake the circuit with a test lamp in between ( one side of T/lamp to battery post & t'other to battery clip/clamp.)

 

The test lamp will be on if there is a drain ( current flowing ) now start switching/disconnecting items to see if t/lamp gets dimmer.

 

Above is more easily done & observed if working single handed -- unlike trying to see a meter reading.

 

When test lamp is no longer glowing then there is no current flow/battery drain, if impossible to get a "No Glow" situation then a high resistance cable fault to earth is probably the cause.