Battery drain 4A draw with nothing on...

[Lonnzo79]

So I recently got a new battery, the old one was toast, wouldn't hold a charge.

I went and got a new Duralast Gold, working fine for a over a month.

Mysteriously, after work I came out and it was dead, jumped it and got home, only a mile away.

Charged the battery back up to full, no problems. I disconnected the ground and did a Amp draw test and it read around 4 amps with the doors closed and nothing on.

Pulled all the fuses, no change, still 4A draw. I removed the line (the one that's bolted down with a 10mm Nut) running after the 100A fused link by all the engine bay fuses and it drops to normal, around 10mA.

My question, where do those 2 wires go that are on the back side of the fused link?

Battery-------------->100A Main fuse------->2 black lines, one with a yellow line for sure.

I don't have time right now to jack it up and look around the engine and under to track them, just wondered if someone knew off the top of their head where those 2 wires headed, they are pretty large, probably 10 or larger that run to that post

Thanks

Lonnie

 

[pcb]

 

[pcb]

You may have a bad alternator. When mine went bad, it drained my battery overnight.

Try testing for that 4 amp draw at the alternator connector.

Another easy way to test your alternator is to disconnect the neg. battery cable while the engine is running. If the engine stalls, the alternator is bad. (I've done is to my car a few times with no problems).

 

[Lonnzo79]

Thanks for the response, I'll test it this weekend, I got a new alternator and belt because I figured that was it, hopefully I'll have time to throw it on this weekend. Got a TYC alternator and Gates belt, just trying to decide whether to pull it out the bottom or top. I really like this little P5, I have a slight tick when I barely step on the accelerator or get around 4k RPM's. Not sure if it's a bottom end problem, valve lash, or the flaps on the intake, 220k on the engine, 240k on the body. I've been thinking about a new engine or a rebuild on mine but the rebuild kits are a just a couple hundred less than buying a used fsde off ebay. Any input, I'm not rich, wife and kid with mortgage and all but I'd like to see this car running on a fresher engine, possibly with a turbo.

Thanks

 

[gfsmith87]

NEVER DISCONNECT THE BATTERY WITH THE ENGINE RUNNING.

On older cars this was a way you could test the alternator. In a newwer cars with ECM, BCM, TCM, etc... NEVER DISCONNECT the battery with engine running. These controllers have semiconductor chips that are sensitive to voltage spikes and transients which become pronounced when battery is disconnected.. Even the power diodes in the alternator can be stressed and eventually damaged. If you suspect the alternator you can take it of and have it checked at nearly all autoparts (Advance Auto Parts, Autozone, ect) stores.

 

[pcb]

I was wondering about that but I have done it twice on my car and even reconnected it while it was running and had no problems.

I have heard of some alternators testing good on the bench test when they were bad but the battery disconnect method worked.

I won't be doing it again for interest sake but if I end up with a dead battery I'm pretty sure I'll do it again. Removing the alternator is a PITA on this car (the CV shaft needs to be removed to get it out of the engine bay) but it takes just a minute to disconnect the battery for a quick easy test.

 

[kamesama980]

It's on the "don't" list not because it'll do damage every time but because it'll do damage (numbers out of my butt) 1 time in 10). Might be acceptable odds in some places but with hundreds of dollars computer parts with other test methods available, it's not the best for cars.

It might prove a dead alternator, but it doesn't prove a good one. Alternators can fail in many ways, several of which will allow things to still run but fry the battery and computers in the long run (diodes leaking AC comes to mind).

 

[surefire2007]

Would like to know -
How did you fix the problem?
I have 2002 protege LX. I got the battery sign while on road. Traveled about 200 miles and park in Garage. Battery voltage were about 12.5V. Raising speed boost up to 13.3 but not 14.5V. Suspect alternator. So brought one rebuilt alternator from advance auto part with new Dyco belts. Gave to my Mechanic and he replaced it.
When he started car the alternator voltage went up close to 17V!! Now we do not know why? Is this car has internal regulator? Or Computer controlled ECU?
May be bad rebuilt alternator? or regulator i.e. ECU? Or bad connector? I learned some one had the similar problem but did not show how did he/she fixed!
http://www.mazdas247.com/forum/showthread.php?123742148-Protege5-Alternator-Overcharging