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    battery parasitic drain

    got 155mA drain going on killing the battery in a day or so, pulling fuses and relays in fusebox under the hood one at a time didn't find anything other than when 21 is removed it drops 10mA from 155mA to 145mA a couple others cause about 1 or 2 mA which is nothing. there is an additional 140mA coming from somewhere? previously when i did it a year or so ago it was less than 15mA

    couple things of note is the lights that go on when door is opened dont work anymore and the passenger door wont unlock with the battery disconnected but there drivers door will.

    i'm going to try unplug ABS relay and check out the lights and switch on the door when i get a chance

    where else should i check?
    Last edited by digger; 10-29-2017, 05:23 AM.
    89 E30 325is Lachs Silber - currently M20B31, M20B33 in the works, stroked to the hilt...

    new build thread http://www.r3vlimited.com/board/showthread.php?t=317505


    #2
    My guess is a water leak into your door lock module/interior light relay. It's in the speaker cavity.

    Or ABS relay - that's another one to try.
    Originally posted by Matt-B
    hey does anyone know anyone who gets upset and makes electronics?

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      #3
      Turns out lights do work when you put them in correct position. I pulled abs relay and it made no difference.

      I started pulling wires off the terminal block under the hood. Removing fred to fuse box does nothing but removing another wire from the block does. Each in isolation does nothing but combined it has an effect. Would that be ignition switch issue ?
      89 E30 325is Lachs Silber - currently M20B31, M20B33 in the works, stroked to the hilt...

      new build thread http://www.r3vlimited.com/board/showthread.php?t=317505

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        #4
        What year and ECU setup is in your car? the ETM shows everything connected to the distribution block maybe it'll help you narrow down what is drawing the current. This is the one for my 87.

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          #5
          here is my terminal block/power distribution block



          removing lead to fusebox doesnt solve the issue.
          removing any other individual lead (those that can be) does not solve the issue

          removing lead to fusebox and any other and drain falls back to normal. for example removing the wires to fusebox and pump simultaneously makes the drain stop but individually they dont. why would they be related?

          the pump is an aftermarket vacuum pump that i have had installed for a few years, the wire goes to a separate relay and fuse that energizes with ignition turned to in on position.

          ive removed ABS relays, unplugged ignition switch, unplugged radio.
          89 E30 325is Lachs Silber - currently M20B31, M20B33 in the works, stroked to the hilt...

          new build thread http://www.r3vlimited.com/board/showthread.php?t=317505

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            #6
            Interesting that removing fuses does nothing but removing the feed to the fuse box with something else does. I'm sensing a short or a sticky relay.
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              #7
              Maybe try removing everything from the distro block except the main (large) feed from the battery. This includes the small fusible link wire from the battery to your pump.

              Then connect each individual wire separately and check the current draw each time. If they all check out ok connect the fuse box wire permanently and then try each of the other remaining wires individually with it and see which combination causes the draw to appear.

              If it still doesn't show the draw, keep trying different combinations eg pump and starter, pump and abs etc. Eventually you should be able to pin down the troublesome circuit and then start looking for shorts to ground etc. Don't connect the fusible link wire to anything until you have tried all combinations using the main feed as the power source. Its just a parallel feed from the battery and will complicate the troubleshooting process.

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                #8
                Pretty much the fuse wire and any other wire removed from block causes issue to go away (I will double check again) The pump just happened to be the easiest of others to take off. I'm not convinced it's anything to do with pump but going to rule it out more thoroughly. One thing that's been done is it's been fully resprayed and jumpered several times by people who don't know better
                89 E30 325is Lachs Silber - currently M20B31, M20B33 in the works, stroked to the hilt...

                new build thread http://www.r3vlimited.com/board/showthread.php?t=317505

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                  #9
                  In your photo, the wire labeled "pump" doesn't seem to attach to anything. In stock configuration, that's the fusible link and should only power the main relay (the wire you have on the side of the block), then the pair of wire bundles from the fuse box should attach top the side of the block at the 10mm and 8mm hex screws. Probably not your issue, but I do know that the race cars act funny via the safety electrical cut off if the main relay doesn't isolate all the way to the battery terminal.

                  I had an issue once with circuit #21 and it turned out the battery charger in the glove box had something shorting over the terminals. I removed the positive lead from the back of the flashlight socket and it went away.

                  Looking at the ETM, there are only two things that are dedicated to #21, flashlight charger and trunk light. Perhaps start there?

                  As far as the door lock, I have had a lot of the door wiring connectors fail recently. Disconnecting them at the door jamb, cleaning them and some dielectric seems to be the trick.
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                    #10
                    Nothing like an electrical ghost to waste a bunch of time, look at the thread I just posted the other day about my fuse 21 and radio problems :p. It's the memory power circuit for a bunch of systems in the car as well as the trunk and dome lights, glove box like FF said, took hours to diagnose and fix. Turned out the same corroded splice issue was affecting a bunch of other circuits too, the weird thing is the dome lights and trunk light worked fine, I guess because the low voltage due to the resistance in the corroded splices only made them a bit dim, where the stuff that was sensitive to under-voltage conditions was going haywire. I'm going to check my other car before the carpets go back in it was a swamp when I got it. Old cars are fun right! Def let us know if you figure it out so we can add it to the list of stuff to check for!
                    Last edited by J0dylan; 11-01-2017, 09:45 PM.

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                      #11
                      the pump attaches to the fuseable link feed in that feed. ive since changed that since the cable to relays should be there (hasnt been there since forever lol).

                      found out the relay for pump was wired wrong i had the switched 12v and 12v battery switched at the relay socket so the ignition was powering the pump, luckily it only runs for a short period intermittently (it is also fused anyway)

                      ive also seem to have narrowed it down to 21 and 27 fuse combinations, was doing some checks with door open and lights in off position and i heard what sounded like the switch on the door jamb making a noise so pulled out all interior light relays about 4 different ones i think and a couple others i ruled out. need more daylight though
                      89 E30 325is Lachs Silber - currently M20B31, M20B33 in the works, stroked to the hilt...

                      new build thread http://www.r3vlimited.com/board/showthread.php?t=317505

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                        #12
                        Fuse 21 powers the cluster or more importantly, the SI board. Once the SI board batteries die, they will cause a drain like you are experiencing, this is very common. Try disconnecting the cluster or pulling out the SI board and you may find the drain goes away.

                        If you confirm its the SI board, it will need to be refurbished.
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                          #13
                          155mA is nothing. Like, less than a single LED draws kind of nothing. No way that is killing your battery in a day. Something seems fishy.
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                            #14
                            Originally posted by AndrewBird View Post
                            155mA is nothing. Like, less than a single LED draws kind of nothing. No way that is killing your battery in a day. Something seems fishy.
                            AndrewBird, I will have to disagree with you. 155mA is more than enough to drain your vehicle battery. The normal current drain of most cars is between 15-30mA. 155ma is definitely not normal.

                            An LED draws about 5mA-10mA.
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                              #15
                              ^ditto. But the e30 does have some power hungry modules - the stock delay unit can ruin your day when it's going bad. In colder weather you can actually feel something drawing 100mA - it will be warm to the touch, or lit up like a christmas tree.
                              Originally posted by Matt-B
                              hey does anyone know anyone who gets upset and makes electronics?

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