On sunday the radio stopped working all of a sudden. the next day the battery was totally dead. i have checked the fuses on the radio, none are blown (checked arial and cigarette lighter and fuse at back of radio) so i assume the radio itself is bust. still it seems a bit odd that it ran down the battery. the radio does not oppererate unless the ignition is on usually.
Does anyone have any idea why the battery would have drained?
Possibly the battery was so flat it could not work the radio but kept the engine running. If you switched the lights and heater on it would have stopped the engine.
Try charging the battery, if it goes flat again it’s either the battery is shot or the charging system is’nt working.
The clowns who installed our radio hooked it up to a permanent live so even off, it drained the battery. I don’t know how, I’m no electrician - but since the radio was removed we’ve had no isues with the battery, even when the car had been stood for 10 weeks over the winter. Prior to that the radio would drain the battery in about 2 weeks, sufficiently that the car wouldn’t start.
I have a charger being delivered tomorrow.
I dont think that this was the case as the radio died sunday morning. parked up at about mid day and then went out again at about 6. the battery was then dead on monday evening when i tried to shift the car. if it was so low on juice that it couldnt power the radio then it definately wouldnt be able to turn over the starter motor. everything else was functioning normally. the battery has not shown any signs of dieing.
Thinking about it the radio must have some sort of constant feed as it is able to maintain preset stations but loses them if you disconnect the battery. maybe it broke and was left switched to perminantly on
You need to check the “dark” current from the battery. ie. When everything is switched off including the radio and the doors closed and with the boot lid light off (you can switch it off by flicking over the catch with a flat bladed screwdriver).
Disconnect the -ve (earth/chassis) side of the battery and use a digital multimeter set to the 10 Amp range and test between the battery post and the cable terminal. Should be little or no reading. If so, set the multimeter to a lower range, say 200 milliamps and test again. Should be no more than 20 milliamps. If more then you have an electrical fault somewhere running down the battery.
If OK then I would suspect the battery. Charge it by all means but at not more than 3 to 4 amps and use an intelligent charger if possible like an Optimate or CTEK. If it charges up (and your above reading of no more than 20mA is OK) but goes flat again in a short time then a new battery is probably required.
A fully charged battery in good condition on the bench with no currant drain will read around 12.7 volts and should stay that way. A faulty battery will charge up to nearly 12.7 volts but will drop to 12.2 or 12.3 volts within a day or two and should be replaced.
Hope this is of some help.