

| Subject: | Re: Fw: Auxillary battery not charging |
| From: | David Beierl |
| Date: | Thu, 21 Sep 2000 10:48:25 -0400 |
At 09:08 9/21/2000, Puzerewski wrote: > > If it is not, then you need to check to see that the relay is hooked up > > properly... > >This is how it is hooked up. > >thick red wire from relay #30 to positive post of aux battry Ok, good >2 red wires from positive post of aux battery to fridge fuse box Irrelevant but ok. I'm *assuming* that you removed the existing wires supplying that panel. Also no need to use two wires since they were only separate so as to allow the engine to control the fridge. >blue wire (in plastic sheath with red wire...comes from front of van)to >teminal 85 on relay Ok -- VW hooked it to terminal 86 but it doesn't matter. This is the alternator sense lead, goes positive when the alternator is charging. >.. >red wire (another in said plastic sheath) to terminal 87 of relay Bad. Very very bad. This wire (red/black actually according to Bentley) is a tiny wire which provides a ground to terminal 85 (or 86) to activate the relay. It's actually connected to terminal 50 of the ignition switch, which provides ground *through the starter solenoid* except when the starter is actually cranking (As far as I'm concerned this is over-engineering -- it prevents the relay from activating in the utterly remote (IMO) circumstance that the starter kicks the engine over fast enough to start the alternator charging). If by some mischance you had gotten the relay to activate, would have engaged the starter for as long as it took until the little wire to the ign. switch melted. One hates to be a scold, but messing around with battery wiring without knowing *precisely* what you're doing is DANGEROUS. That wire should go to terminal 85 or 86, whichever one you're not using for the blue wire. >brown to grond relay to inside of battery box. I don't know what terminal you hooked this to -- or to relay case?? but Thank God it didn't work. What are you using for a negative connection to the aux battery? What you need now, assuming the Bentley diagram for 80-85 camper is correct, is to get rid of the brown wire entirely, and run a 6.0mm (?10ga?) wire direct from the other battery positive to terminal 87 on your relay. This will duplicate how VW did it. It will *not* allow you to parallel the batteries for starting -- you need much heavier wire for that, along with some manual method of connecting them. Some folks would have you put a fuse in that wire right at the primary battery (VW did not). I think that's a good idea, but to be consistent you also need a fuse at the secondary battery in the line going to terminal 30 of the relay. BUT! Don't believe me! Check for yourself, by eye and/or with a meter, that the connections you're using go to the right places *before* you hook them up! This is along the lines of "Never believe anyone who tells you that the gun is unloaded -- check for yourself." The consequences of shorting a battery circuit can be...um...significant. david David Beierl - Providence, RI http://pws.prserv.net/synergy/Vanagon/ '84 Westy "Dutiful Passage" '85 GL "Poor Relation"
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