1985 Van -- Battery drain

[jermiey]

Hi,

I have a random battery question. My battery has been draining on my not very driven 1985 Toyota Van. I recently replaced a 1 year or so battery (with 0 remaining cells) with a new battery. But after 4 days of replacement and not driving, the van doesn't start. I had jump it and they noticed one of the wires throttling the voltage of the batter (grey one in the picture below). He recommended replacing the wiring. My question... anyone have advice on what to replace? Or what could be causing the battery to drain like this? Any help is appreciated, thanks.

[timsrv]

Hi and welcome to TVT! I would not replace that grey wire unless it was burned, corroded, or otherwise open. That is your FL 2.0L fusible link featured here in THIS THREAD (https://www.toyotavantech.com/forum/showthread.php?136-The-fusible-link-thread&highlight=alternator+diode) (1st post near the bottom).

A drain this size sounds suspiciously like a shorted diode inside your alternator. Here is a quote from another thread:


For troubleshooting go to the little plastic "+" box (under & slightly forward of your air intake tube) & open it up.

http://i8.photobucket.com/albums/a23/timsrv/TVT%20pics/electrical/plus%20box%20closed_zpsekr2jrhz.jpg

http://i8.photobucket.com/albums/a23/timsrv/TVT%20pics/electrical/plus%20box%20open_zpsnk46phdb.jpg

Being careful not to touch your tools on any other metal surfaces remove the 10mm nut from the stud. Now remove the eye terminals from the post & touch them together. If they spark or arc, then you have a shorted diode and the diode assembly will need to be replaced. Protect these wires from touching any metal surfaces & before going any further disconnect the battery! Removing the alternator with the battery still connected can be very exciting :yikes: .

Note: For that "spark test" to work you will need to have a charged battery hooked up. FYI, that thread has other valuable info and links to other useful information. To get there just click on the little blue arrow at the beginning of that quote and it will take you there. Also, in the future, before making new posts, try our search feature and read up on the subject. If/when you're ready to post, ask your question in a thread of the same or similar subject matter. Good luck and I hope this helps. Tim

[Jan-Willem]

Yes, just take a multimeter, on amp setting, and measure (with a charged battery, and the keys not in the ignition) the drain to that cable. Then pull each fuse, to see if the drain is still there, then the alternator at that + junction box. I found my drain to to be the voltage regulator wire to the alternator (that little cable with the yellow plug near the battery), so I had to replace the alternator.

[timsrv]

Then there's the classic issue of a worn ignition tumbler releasing the key before the ignition is turned completely off. Make sure to push the button on the column and turn the key all the way to off before removing the key. If you look close at the tumbler there are marks/labels showing position.

[89van]

To add onto this, if you can pull the key out while its in any other position without using the LOCK button above it, don't forget about it. Very easy to do, and since mines worn smooth the horrid shrieking of the "Hey the ignition is still on!" alarm reminds me not to forget.:lol: