Need Help!

Exciter.

 

https://www.youtube.com/watch?v=QPl7CTb685I

 

This happened with my Suby. Was missing a ground. I hit that and the thing started working.

Sounds like a DEAD ALT.     Car runs, yank battery cable, alt. puts out nothing, car dies....

Could be a bad engine/trans ground. I ran three grounds. Two heavy braided ones from either end of the trans to separate points on the frame. The negative battery cable goes right to the starter bolt, and there is a light 10 gauge wire from the battery to the chassis. Clean all connection until they are shiny, bolt them down real tight using a star washer, and then paint to prevent corrosion.

 

Take a voltmeter and measure from the hot lead to the alternator case, see if more voltage is there(13.5 +). If not, is your idiot light circuit working? If the alternator can't see a ground through that bulb, it won't charge. If all checks good, pull it and have it bench tested at a local auto electric store.

Just to clarify the "61 wire" aka the alt light, gets wired from the 61 terminal on the alt ( not B+)to the ground side of a bulb , the center ( hot) of the bulb goes to Ign. on the ignition switch.

Of course, Alan is right. I guess I am getting forgetful. What I should have said, is that when you turn the key, 12v goes from the ignition switch to the bulb. The other side of the bulb goes to the field of the alternator(This wire should be seeing a ground, engine off). The light SHOULD come on, key on, engine NOT running. If it doesn't, that is most probably the issue there. The light goes out when the engine is running as the voltage on the alternator field wire is the same as the voltage at the ignition switch. No voltage difference means no lit bulb(bulb lit=not charging).

 

Alan, thanks for giving my CRS a kick!

Dan Stweart:

 

Rather than tear your hair out, pull the alternator and find a local automotive electrical shop that can run it in a test fixture and tell you whether it's working properly or not.  Those fixtures also have a load source that represents "real world" operation and can stress it to max parameters.  The test is often free or under $20 bucks.  DON'T go to AutoZone for this - find a real automotive electrical shop for it.

 

Once they give it up or down thumbs you'll know what you've got and might even get some solid tips about proper installation and what to look for.  As mentioned above, clean up your ground and + power connections and make sure your dash light is (a.) working and (b.) connected to the proper place on the alternator.

Quick tests:

 

You should have ...12 volts static and 13.8 volts running.

 

Pulling battery cable and motor quits confirms you are running on the battery.

 

Run ground from the alt housing and see if there is any difference (will confirm a ground)

 

61 wire as discussed .....this excites the alt into the charging phase.

 

I am going to place my coins on a dead alt.

 

Dan,
When you turn your ignition to the 'on' position do both warning lights light up? The light has to 'work' to complete the charging system. Please confirm that you have two operating warning lights.

This is basically the same thing that Danny and Alan are saying above. :/

Ted

If the engine starts, there is obviously a ground to the starter, so how could it be a bad ground?  Is the alternator case insulated from the engine some how?

I want to add that disconnecting the battery from a running alternator risks damaging electrical devices in a car. Plus, it doesn't tell you anything you didn't already know by just measuring the output voltage. In this case, since your alternator wasn't working, you probably didnt hurt anything.

I agree, I've never been in agreement with pulling the battery cable. Just use a volt meter.

Well I pulled the alternator yesterday hoping I would have some luck having it tested. The only places I could find open were Pep Boys & O'Reilly's...both which cannot test these alternators. So I came home and put it back in the car. The dash lights do go out once the car is started, so I'm still confused. Going to try to take it over to a local VW shop this week and see if they are able to test it for me. Thanks for all the suggestions!

 

I've gotten charging tests done at Advance auto while the alternator is in the car. They do it with the car running.

It's pretty normal for the charging light to flash until the revs come up.

If it goes out when underway and stays off at idle after warmed up, you're probably ok.

If your idle is set too low, you may have an issue too.

I like mine at 1000 because it's smoother and helps with the charging.

Check to see if the belt is worn or loose. Do you hear any squeal indicating slipping?

With all that said, my alternator was replaced this winter after almost 20K miles. The bearing was shot. It could be the internal regulator too.

It might be nothing too.

> On Apr 21, 2015, at 12:01 AM, SpeedsterOwners.com <alerts@hoop.la> wrote:
>

I'm with Justin - on never remove battery cable to try to test alternator.  The alternator (unlike the old generator) is electronic and disconnecting the battery will most likely fry the sensitive diodes in the alternator.  For sure don't try it in a modern car with ECU, memory radio and other sensitive electronics.