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Discussion Starter #1
First off hows everyone doing hope all is well.

Secondly my girlfriends car has started to have battery issues ive donw the parasitic fuse test and narrowed it to the f36 fuse if any one has any advice please let me know. I tested the alternator and it is fine. Battery is brand new and the car has been sitting without said fuse and it has been holding a charge. With the fuse in it dies over night or after a few days. Much appreciated.

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That's not uncommon on a Fiat. When you tested the alternator, did you check if it was drawing any power w/ the key off? (Sometimes a diode can "leak".) Is F36 for the stereo? Some drain is normal and the Fiat draws more than some cars. How high was the draw?

One thing to check is the condition of the battery. Have it load tested. It may be time to replace it, especially if it was drained recently. If it's time to replace the batt, try to find the highest Ah battery model you can. A powerful battery can handle the drain, even if it's a somewhat higher load than you'd normally expect.

If the car is left sitting for more than a week, using a battery-minder charger is a good idea.
 

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Thanks for the reply.
So the f36 is for climate control, radio, the cigar plug, and tpms. Not sure if there is more. I did not check to with the car off i checked while it was running for a high enough volt out put. The battery is literally a week old. As i did all of the testing with a fresh battery. With the fuse in it would draw from 1.300 to .40 amps. And i took the stereo startup into account because it trys to do a cd check. But with out the fuse it goes down to about .001 to .004 amps. Battery holds at 12.44 without fuse but drops .01 every 10 seconds with it in. Cant really wrap my mind around where to look. I read about the bcm going bad on these but ours doesnt seem to have that problem. I was worried it was the alternator but it charges just fine. I mean i could be wrong about the whole thing but feel like im narrowing closer. Any thoughts?


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And all the testing was done with the car off with no power draw supposedly. Doors were open but switches were engaged. 2 volt meters were running one for amps other for battery voltage drop.

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I'm not sure, but try this. Put the hood up, pull the negative terminal and pull that fuse. Close the doors and give it half an hour. Now check draw with your meter (negative post to negative post clamp). It should read zero.

Plug the fuse back in, close the doors and give it half an hour and check again. The delay is to allow the interior lights and pause delay for radio shut off to power down. Now it might read as high as .1 A, but ideal would be lower.

You can try removing the cargo tray and check the car after dark to make sure no lights are on. I assume you don't have an aftermarket amplifier in the car, correct?

If the second reading is high, you can try disconnecting components. For instance, the stereo amp should not be on when powered down. You could unplug the wiring harness where it goes into the amp. Of course, that sort of stuff would probably happen if the BCM is going bad... a stuck relay leaving some component energized.
 

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My car sits weeks on end, not been driven. Same with brand new 500 on the studio lots. For months. They all start. Did you check the volt of your new battery? It should be around 12.4 volts. When your car was running, with new battery. Did you have a load test preformed. Is you alternator charging the new battery. 2012-2013 500, has starting issue. It dealt with the starter ground cables. You might have bought another bad new battery off the shelf.
 
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