Focus Fanatic--2004 CX4 Ford Focus--battery draw? electrical problem


#1

Yes I am still driving and jumping my beloved '04 Ford Focus (manual) at 107,000 miles.
Mysterious battery draw for a long time. It’s common and blogged about by other FocusFanatics. Need help. I pulled the radio fuse out long ago.
It has new alternator, new battery (although it may be compromised from the draw downs and the recharging several times while I try to fix this). Mechanic found and replaced the instrument cluster (because there was a short). But battery still draws down quickly–in less that 10 hours. Mechanic gave up. He said he had found the diagram for the “battery save energy” on the circuit board along with the dome light and with the adjustable side mirrors, but that he didn’t know where to go from there and gave up. I don’t know if he checked any relays or switches, or the grounds from the power source into the engine, or if he tested the wire cables from the positive battery pole for wear.
Really really hard to find an competent electrical technician they are all mechanical…and they try but don’t know where to go after the obvious.
I unhook the positive cable from the battery overnight or whenever the car is parked for several hours, and when I hook it back up, car runs great. Love this car. Any help I really appreciate.


#2

It is fairly simple to locate most of the things that cause this kind of trouble using the proper testing methods and test equipment. When current draw on a battery gets over 50 milliamps it can cause the battery to run down. In your case it seems to be much worse if the battery is still in good condition and is fully charged. Here is a link that tells you how to test for this kind of thing.

http://www.aa1car.com/library/battery_runs_down.htm


#3

@Jojina
I Feel Your Pain. This Has To Be Extremely Frustrating, Especially When It Involves A Car That You Otherwise Like Very Much And Would Like To Drive “Forever.”

One thing to try is locate a reputable Auto Electrics Shop, one that works on whole cars. These shops specialize in rebuilding components, such as alternators and starters, but a good shop that works on cars should have somebody on staff that is more adept at problems of this nature than a general mechanical repair shop.

Another thing to try is to buy a device from Harbor Freight that is a digital read-out electrical circuit tester. This tester comes with a battery installed and has a short lead wire that has a 2-blade terminal on the end. The idea is to pull out fuses, one at a time, plug the device in where the fuse was located, and read the current draw. Repeat until you find a fuse circuit with phantom draw.

They come in 2 sizes, one for larger fuses (usually older cars) and one for smaller fuses (usually newer cars). See which size you’ve got before purchasing one. You could pull a fuse and match it to fuses for sale if you’re not sure which one. These sell for less than $15 each, I believe.

Use your owner’s manual to locate all the fuse boxes in the car. Some cars have more than one, located inside the car and under the hood.

If you find a parasitic draw on a certain circuit, your problem isn’t solved, but narrowed down. You then have to find out what on that circuit is causing a problem. The information obtained could even be relayed to a technician to speed up the diagnoses and repair.

This may or may not work out, but for 15 bucks it might be worth a try.

CSA


#4

Good ideas posted above. It’s usually possible to quickly determine which circuit is causing the draw. Once everything is turned off, the car parked, engine not running, the shop will connect an amp meter in series with the battery. That will show how much current is being drawn on the battery. It must be well over 50 mA in your case. Then they’ll pull each fuse, one by one, until they find the one that causes the reading to drop to less than 50 mA. At that point they’ll use the wiring schematic to try to figure out what device is causing the problem.

If it never reads above 50 mA but the battery still goes dead, that could be a bad battery or there’s a chemical short circuit along the surface of the battery between the two posts caused by contaminants on the battery case.


#5

Perhaps you should try to find a shop near you that specializes in automotive electrical systems. They’ll have the expertise and access to the proper technical documents to track the problem down.