Thanks. I will still look into the alternator, but at this point, I think the drain is not the biggest issue - and the alternator seems to be charging ok. I think I am really dealing with two separate issues here - one, the drain (possibly caused by the diodes on the alternator), and two, the fact that the battery is not being fully recharged, meaning that after topping it off with a charger, over the course of several weeks, the battery gets weaker and weaker until on a cold morning or a longer-than-usual sit, it won't start the car. As soon as I charge the battery it runs great for several more weeks until the cycle repeats.precopster wrote:Based on the 80mA current draw you describe in the thread, the alternator is still suspect. Remove the main positive feed (12mm nut) from the alternator & check for the current loss. If it's gone you had still better replace the alternator or regulator.
Bad battery cables cannot draw current, as they are simply not completing a circuit. However they can lead to a battery improperly charging while the engine is running if they are corroded.
Once the battery is disconnected an ohmeter can measure their resistance. The earth is easy enough; find a good ground (such as the engine or chassis) and put your probe on it then connect the other probe to the end of the terminal nearest the battery. The reading should be less than one ohm. For the positive cables the same applies, measuring them at the battery terminal end and to the starter motor terminal and then the alternator terminal.
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WIRING CONTINUITY TEST
1) Connect a voltmeter between generator B+ terminal and ground. Voltmeter should indicate battery voltage. If battery voltage is not indicated, check wiring between generator and battery.
2) Turn ignition on and ensure generator indicator light comes on. If light does not come on, check wiring between generator and warning light.Code: Select all
VOLTAGE DROP TEST - POSITIVE SIDE
1) Connect a voltmeter between positive battery terminal and generator B+ terminal. Start engine and run at 2000 RPM. Turn on headlights, rear window defogger and heater blower.
2) If voltage drop is more than .2 volt, check circuit between generator B+ terminal and starter for corroded or loose connections. Also, check circuit between starter and battery positive terminal.Code: Select all
VOLTAGE DROP TEST - GROUND SIDE
1) Connect a voltmeter between negative battery terminal and generator housing. Start engine, and run it at 2000 RPM. Turn on headlights, rear window defogger and heater blower.
2) If voltage drop is more than .2 volt, check batteryterminals, chassis grounds and engine grounds for corroded or loose connections.Thanks Lee. I will clean up those cables and re-do the above test. The anti-theft switch is my current solution for the battery drain (related, but I believe separate issue - see above), and it works. I can leave my car for over a month and it will start when I return (a common necessity with my job).Ozark Lee wrote:The secondary leads (both positive and negative) look awful. Remove the nuts and throughly clean all of the surfaces on the secondary lead terminals and the main terminal where they mate. I would also get rid of the anti theft switch on the negative lead and just plug the negative terminal directly to the post.
I assume that the lead going to the left from the positive terminal didn't replace the starter lead and the starter lead just isn't visible in the pictures.
...Lee