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Battery drain - not simple.

6.4K views 8 replies 5 participants last post by  nicam49  
#1 ·
Hello everyone,

I bought a Ford mondeo 2004, 2.0 petrol engine.

After 1 week I have the battery flat as a pancake.
Battery was new, with warranty. They replace my battery with another one, and next day battery was flat again!
I take a multimeter and put in series with battery. After 2 3 hours is start to drain about 5 6 amps, stop for 20 min and drain again until battery is flat.
I disconnect all bulbs inside the car, I take all fuses and relay out, but still drain my battery.
I take alternator out, and going to car service. The alternator is in perfect condition and starter too.

I check the battery saver relay and was hot, I take it out and drain is smaller with 0.5 amps. So is not from here.

Please give me an advice, becouse i try for over 1 month to fix this and I can't figure out.
Thank you!
 
#6 · (Edited by Moderator)
I already did this. Is not from fuses or relays. I take everything out as I say and still drain.
Hi, try disconnecting all wires from the alternator and check again for drain.
Also I don't follow your logic: If the drain is 5-6 amps, then if you disconnect the battery saver relay (whatever that is) the drain reduces to 0.5 amps, then SOMETHING isn't right there and needs investigating.
 
#7 ·
Hot battery relay says something is shorting out.

Removing the relay cures it, maybe the relay is faulty. Short circuit internally?
 
#9 ·
Hot battery relay says something is shorting out.
6
Removing the relay cures it, maybe the relay is faulty. Short circuit internally?
Or what does that relay connect to?