View Full Version : electrical woes
gary
September 24th, 2003, 14:07
car is a 70 bug, 1600cc motor, converted to alternator/12v
here's the problem. battery is sometimes dead. takes it forever (8 hours) to charge up, on a battery charger that usually does up a battery in a couple of hours or so. possible bad battery? (it's only 2 mos old)
i was told that you can tell if the problem is coming from the alternator by removing a battery lead (didn't know which one, tried both, same result) while the car is running and seeing what happens. if car dies, alternator is bad. it died....is this a legit test?
then there's the voltage regulator...i know nothing about it, but it's inline between the alternator and the battery...should be sending some juice back to the battery, no? it seems to be okay, as it also powers other things, and they work...
i know auto zone tests batteries and alternators, and they will be testing mine tomorrow, as soon as i get it apart...any ideas?? this bug is sposed to be the daily driver for a little while whilst the truck is getting caged, so i can still get back and forth to work...AAARRGHHH!!!!
tkr
September 24th, 2003, 14:48
I wouldn't rely on Autozone's test to tell you if your battery is ok or not. Taking the leads off the alternator is not a definitve test either. If the battery is dying while you're driving, the alternator and possibly the battery are bad. If its dying after sitting, either the battery is bad or something is drawing power from it. Judging by the long charge time, I think it would be safe to assume the battery is bad. But keep in mind that a bad battery can ruin an alternator, and vice versa. So even if you raplace the battery, you should still have your alternator checked.
orvacian
September 24th, 2003, 18:18
Hey Gary, email me and we can set up a way for me to look at it. With a DVM it should be easy to tell where the problem stems from.
1992f150
September 24th, 2003, 18:31
Way to test if battery is being charged: Start car (jump it if you have too) and read the voltage of the battery. The battery by itself should be, like 12.6? So to charge up the battery the voltage has to be more than this, around 14.x volts should be right. The voltage at the battery while car is running is actually the output of the alternator.
It sounds like your battery might be dead. If they get deep cycled more than 1 or 2 times they can crap out and stop holding a charge. However I have heard a bad alternator can sometimes draw current so this could be sucking the battery down. For the autozone test of the alt, they hook up a belt to your alternator and spin it, and read how much (if any) volts are being put out.
Can't help on the voltage regulator, but if a new one is cheap might want to replace it anyway.
As a side note never do that pulling lead test on anything with computer controlls on it, it can cause serious damage.
ntsqd
September 24th, 2003, 20:12
'70 should have been 12V from the start, which would explain the separate regulator. Most of the 12V conversion Alts are internally regulated.
F150's test of voltage at the battery would be the place I'd start. That it takes so long for the battery to be charged, only to have it flat in a few days makes me think it's internally shorted or partly sulfated. I'd replace it and then look into whether the charging system is doing it's job.
That disconnecting the either lead from the alt kills the car tells me that the Alt is providing the needed electrical power to run the car. And that the battery can't do that.
bajaruner11
September 25th, 2003, 00:32
gary
You did remove the stock generator voltage regulator under the back seat and reconnect those wires correct??? All VW type 1 alternators have there own regulator attatched to themselves either internally or directly on top. On a VW alternator the D+ terminal on the alternator is part of voltage regulator.
If not then there is your problem.
gary
September 25th, 2003, 00:49
thanks to everyone for their input...
just to clarify a bit...
TKR...
leads(cables?) were taken off at the battery, not the alternator. sorry if i was unclear on that. it's a test i'd never heard of, so i tried it. the battery has died after sitting and while driving...and immediately after turning on headlights, once...but not every time..i've traced the headlight wires for shorts, and cant find any bare wires or anything of the sort....didn't actually die immediately, but they went dim and the car died within about 10 seconds....i ended up driving it home with one of those jumper/booster packs attached to the battery.
ORVACIAN...
thanks. i emailed ya. check the earthlink addy...
F150...
sounds good to me...hopefully i'll be trying that with orvacian soon????
NTSQD...
my bug knowledge is next to none, but my friend bought the bug, and dropped in a new motor recently, so i'm going off what he's told me...the battery has actually only been charged once now, and so far it's holding up.
after more thinking, i've got a question. this motor had never ran until the new battery was installed. is it possible that the alternator has never worked, and the car has just been running off the battery power for that long? took it 2 months to finally kill it? as far as powering the lights...it's all off the regulator, and it's all off the same terminal. a wire comes off the positive post of the battery, and goes into the regulator. it attaches to the same terminal that the power goes out of the regulator from, to the rest of the car..(lights, wipers, ignition stuff)...
just wondering...
gary
September 25th, 2003, 00:53
BAJA...
please explain...the regulator i'm talking about (still connected) IS under the back seat...how would i connect without it? i don't know if it's a stock vw alternator or not..
bajaruner11
September 25th, 2003, 01:33
gary
You have found your problem! The regulator under your back seat is for a generator only. All alternators for type1 VW's have there own regulator directly mounted to the alternator. To complete your conversion you must remove the generator's regulator under the seat and reconnect the wires that run to it. To do this simply connect all (3) large red wires together preferably by soldiering. These are your power wires one going to the battery the other to your starter. Next connect the green wire to the blue wire again soldier, this wire goes to your dash light. The last wire should be a brown wire and is not really any longer needed all it did was connect a ground between the regulator and generator if you like you can ground it to the chassis. I think there where a few alternators that had a remote regulator but the chances of you having one of these if you bought a conversion kit is slim to none I have not seen one in years like this. Either way the stock generator alternator must go.
Hope this helps
Steve
gary
September 25th, 2003, 01:35
sounds like a plan...would this have prevented the alternator from sending power back to the battery??? weird, cuz it's been fine for like 2 months now..
bajaruner11
September 25th, 2003, 01:45
yes and also it's possible that having things wired wrong somthing burned out. Even the battery can be damaged
gary
September 25th, 2003, 14:18
i called the place the motor came from this morning. they said it should not have a regulator, and agreed with your wiring...much thanks!!! they did not have an answer for why the regulator came with the rest of the stuff for the motor...just a mistake, i guess. now, to get the wires switched, and battery tested (just in case it's damaged) and see what happens.
thanks again!!!!
gary
September 26th, 2003, 13:58
battery tested fine (after a night of charging), wires are reconnected, without the regulator. fingers are crossed..running fine now, we'll see in the next few days what happens.
thanks again to all who helped!
bajaruner11
September 27th, 2003, 00:14
Gary
Get a hand held volt meter and connect it to the battery to see if the alternator is charging. With the engine running at a high idle or faster, the volt meter should read 13 volts minimum. Normal is around 14.7 volts.
Let me know what happens.
Steve
gary
September 27th, 2003, 00:33
one more question...
the idiot light in the dash came on for the first time tonight on the way home, for like 5 secs, then went out. is it sposed to be on when everything is good, letting you know all is well, or when something's bad? or maybe a short/bad ground in the speedo cluster, as only one other light works in there...
sorry for all the questions, but i've never had a bug before...don't know how it's sposed to work... http://www.race-dezert.com/vb3/attachments/old/images/graemlins/smirk.gif
bajaruner11
September 27th, 2003, 09:14
The two little lights at the bottom of the speedo are warning lights this =bad. First are you sure it was the one for the alternator and not the oil light? If so check the connections of both wires running from your alternator for looseness, and good clean contact. Make sure you check all contact points alternator,starter, battery, and your new connection under the seat for the red wire, and for the blue wire alternator, under seat, and dash light. A loose or corroded connection particularly on the blue wire can make your light come on or glow. Also a very low idle even briefly will make the light come on for a moment. Nevertheless still run a voltage test to see whats being put out by the alternator.
gary
September 27th, 2003, 11:00
wonderful, since now it's staying on all the time. it is the alternator light, as i followed the blue wire up to the speedo housing, and put the bulb in it myself, when redoing the wires yesterday...hopefully getting the voltsfrom the alternator checked soon, as my voltmeter isnt working...
CRAIG_HALL
September 27th, 2003, 14:34
Make sure the light is working properly. I think the alternator light needs to be working to charge correctly.
ntsqd
September 27th, 2003, 22:26
The wire that light is in is the 'Exciter' wire to the Alt. When you turn the key to the run position this wire feeds 12V to the field windings of the Alt. to excite it and start it charging. System looks something like this:
Batt+ -> IGN SW -> light -> Alt field windings -> ground.
If the Alt isn't charging the light goes to ground thru the field windings which turns on the light. Once it starts charging the light will go out because the Alt feeds 12V back up the wire. So the light now has 12V positive on both sides. Can't light up if it can't go to ground & complete the circuit.
If the light is coming on while the engine is running you've got one of two things happening. Either the wire has a short in it and is going to ground btwn the light and the Alt., Or the Alt isn't charging for some reason.
gary
September 28th, 2003, 00:41
wow, this just got tougher...
since the instument cluster thing is pretty much dead, this complicates things...i hope to get it volt tested soon, maybe it'll clear things up a bit. good chance i'm gonna havta bypass the light thing somehow...just run a wire from ignitionon to previous light wire? or am i missing the ground part that way?
bajaruner11
September 28th, 2003, 01:27
Gary
These alternators are very simple units The large red wire ultimatly goes to the battery, and the blue wire runs to the idiot light that's it. If one or the other is not right the altenator does not charge. Try this unhook both wires at the alternator, run a positive wire from your alternator to the battery from the post the large red wire hooks to. Run anouther wire from the other terminal on the alternator to the dash light. If the alternator works ok you have a wiring problem if not go get a new alternator. That's it. Hope this helps you figure this out.
Steve
gary
September 28th, 2003, 01:46
sorry for all the questions...i get what you and ntsqd are saying about how the alternator works off the light (kinda), but i'm sure the cluster isn't all there. this bug was gonna be stripped down and made into a prerunner/5-1600 type car, but then the project was scrapped. there are almost no wires on the back of the speedo. no lights at night, fuel guage doesn't work, no indicator lights of any kind. lots of open light sockets and tabs with no wires on 'em. i'm just wondering if/how you would abort the speedo/idiot light part of the charging system, as i really dont wanna havta rewire all the wires on the back of the speedo...if i understand what you're saying, there has to be some kind of power going to that light thru the speedo...it isn't there, i'm almost positive of that...so can i work around it? not trying to make this harder than it is, just trying to outsmart the vw charging system a bit....
CRAIG_HALL
September 28th, 2003, 11:29
You can check it at the back of the car. Simply get a small light and hook up a positive lead to it,the other end to the small male spade terminal on alt.It should ight up.Whan motor starts th light should go out-showing charge to the wire.-----Just dont leave the light wired this way-the hot lead needs to be "key on". or this light will always remain on-draining battery.
ntsqd
September 29th, 2003, 10:48
Sorry Gary, I was hoping that would help. Think of wiring as being plumbing if that helps.
If you don't want to mess with sorting out what got left working & what didn't you could string a whole new wire for the Alt exciter wire. Just find a ignition-on only terminal on the ignition switch. Run a wire from there to a some sort of two wire indicator light. A light that grounds thru it's case will not work for this. Then run a second wire from the other side of the light to the small terminal on the Alt.
B4 you go to that trouble, try this in the sequence written:
I think you said the stock light in the dash is/was coming on, that tells me it is/was working. If you pull the socket out of the rear of the speedo cluster and trace each wire, one will go either to the fuse block or to the ign switch. The other will disappear into the stock loom. Disconnect the 'other' wire and ground that now bare terminal on the socket against bare body metal. Then turn the ign switch on. The light should glow. If it doesn't replace the bulb and try again.
Once the light glows like this, hook the other wire back up and install the socket in the speedo cluster. Now turn the ign switch on. The light should still glow.
Start the engine and rev it slightly. The light should go out. If it does, you're good to go.
If it doesn't go out, turn the engine off but then turn the ign back on. Light should be on.Then disconnect the small wire at the alt. The light should go out. If it does not, then the wire is the problem and running a new wire from the terminal on the back of the light in the speedo to the alt should fix the problem.
If the light does go out when you disconnect it with the engine off but does not go out when the engine is running, then you've got a problem with the Alt. Usually either the regulator or the brushes have failed. They are a single unit that can be pulled out of the alt with the engine in the car. If you have a friendly parts guy you might see what the cost of a regulator is compared to a rebuilt alt. It's far less work to pull the regulator out than it is to pull the whole alt out.
HTH
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