Parasitic drain problem - confusing results?
03-02-2015, 04:46 PM
#12
I don't see an Alternator causing a draw but just to eliminate it, unplug it completely and run your draw test again. 50 milliamps will drain a battery over time. I don't know Honda's spec but Toyota (where I work) minimum allowed parasitic draw is 20mA or less. Wen I did a draw test on my s2k before installing a lithium battery I was only seeing 7-8mA after the car sat for 30 minutes and that number never deviated until I opened the drivers door.
03-02-2015, 05:43 PM
#13
I don't see an Alternator causing a draw but just to eliminate it, unplug it completely and run your draw test again. 50 milliamps will drain a battery over time. I don't know Honda's spec but Toyota (where I work) minimum allowed parasitic draw is 20mA or less. Wen I did a draw test on my s2k before installing a lithium battery I was only seeing 7-8mA after the car sat for 30 minutes and that number never deviated until I opened the drivers door.
No idea about the alternator though, I guess it could have an internal defect , if the draw goes down to about 7mA with it removed then you probably have your source.
03-02-2015, 05:43 PM
#14
I don't see an Alternator causing a draw but just to eliminate it, unplug it completely and run your draw test again. 50 milliamps will drain a battery over time. I don't know Honda's spec but Toyota (where I work) minimum allowed parasitic draw is 20mA or less. Wen I did a draw test on my s2k before installing a lithium battery I was only seeing 7-8mA after the car sat for 30 minutes and that number never deviated until I opened the drivers door.
No idea about the alternator though, I guess it could have an internal defect , if the draw goes down to about 7mA with it removed then you probably have your source.
03-03-2015, 09:38 AM
#16
When I took out the 15A alternator fuse my reading dropped to 0.00 so I guess < 10 mA? Would this be abnormally "low"? I think I'll take the alternator out this weekend and run it up to advance auto for an exchange... but I really don't want to unless it's the only culprit.
03-03-2015, 10:18 AM
#17
Are you getting good voltage values off the battery? Engine off and at idle. Car at 1500RPM's --- with and without load. My guess (and it's a WAG) is that one of the diodes in the rectifier maybe bad. Draining voltage to ground, when engine is off. Or short in regulator. Volt readings should reflect this.
https://www.youtube.com/watch?v=nQysE2oJAuo
http://www.youtube.com/watch?v=nQysE2oJAuo
https://www.youtube.com/watch?v=nQysE2oJAuo
http://www.youtube.com/watch?v=nQysE2oJAuo
03-04-2015, 03:36 PM
#18
Pulled the alternator when I got home from work today, took it down to advance auto and it tested bad on their bench. So, for future reference, even if you only have a 50 mA draw through your alternator (like me) it will test 'bad' at least on their machine. I was worried, since I didn't know what the spec limit was on their machine - especially everything else with the alternator is fine.
Luckily mine was covered since I bought it 11 months ago so I get a free replacement
Luckily mine was covered since I bought it 11 months ago so I get a free replacement
03-04-2015, 03:49 PM
#19
Good job. Your diagnosis procedure worked!
03-19-2015, 07:55 AM
#20
I forgot to clarify on what I found out after installing my new alternator. When I reinstalled it I checked the drain at that point and it surprised me that it was still 0.05... I was kinda mad. Then I realized that I have an Odb2 Bluetooth device that I always leave plugged in. When I unplugged it the drain went to zero! Which I kind of thought was crazy... Considering when I pulled the alternator fuse it went to zero before. Does the odb2 port wire through the alternator somehow? Anyways, I had no idea those devices have a moderate drain. I think my alternator went bad because it would drain too hard and it was a hard start for my alternator each time so it went bad prematurely - leading it to test bad at advance auto.