Hello! Log in or Register   |  Help  |  Donate  |  Buy Shirts  See all banner ads | Advertise on TheSamba.com  
TheSamba.com
 
Burning alternator warning light wire
Forum Index -> Thing/Type 181 Share: Facebook Twitter
Reply to topic
Print View
Quick sort: Show newest posts on top | Show oldest posts on top View previous topic :: View next topic  
Author Message
dagimp
Samba Member


Joined: July 30, 2008
Posts: 264
Location: Philly
dagimp is offline 

PostPosted: Tue Sep 04, 2018 6:39 pm    Post subject: Burning alternator warning light wire Reply with quote

A few years back I did an alternator conversion to my 73 Thing. Worked fine until a month ago when it stopped charging. Brought it in and mechanic diagnosed it with a failed alternator. Replaced the alternator with a Bosch. I drive it 5 mins home and sits for 2 weeks. I start it up and drive it for .25 miles, generator warning light goes on and smoke starts coming out from behind the dash. Drive home... more smoke. I checked and the melted wire is the blue and black striped wire which looks to be the generator (now alternator) idiot light, which also goes to the brake warning light. Wire is totally melted and exposed for a good foot behind the dash. What could possibly be the issue? Thanks!
_________________
Buck

1973 Orange VW Thing, "Otto".
Back to top
View user's profile Send private message Gallery Classifieds Feedback
dagimp
Samba Member


Joined: July 30, 2008
Posts: 264
Location: Philly
dagimp is offline 

PostPosted: Thu Sep 06, 2018 5:04 am    Post subject: Re: Burning alternator warning light wire Reply with quote

More followup/questions to this issue. The melted wire behind the dash is a blue wire with a black stripe. it splits behind the dash and one end goes to the Generator/idiot light and the other to the brake warning light (which is always on, but that's another issue). From the wiring diagram posted here, I assumed the other end went to the alternator, but when I unplugged that wire from the alternator, the Generator/idiot light went out but the melted wire still has power. Help!
_________________
Buck

1973 Orange VW Thing, "Otto".
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Captain Spalding
Samba Member


Joined: February 19, 2005
Posts: 2483
Location: . . . in denial.
Captain Spalding is offline 

PostPosted: Thu Sep 06, 2018 8:08 am    Post subject: Re: Burning alternator warning light wire Reply with quote

Yep. The wire that goes to the generator is hot whenever the key is switched on. It get's power from the unfused side of fuse 1. It gets its ground from the voltage regulator (in this case the internal regulator in your alternator).

So when you turn the key to on, but haven't started the motor, power flows from fuse 1 to the gen light and then to ground through the voltage regulator. This is for the purpose of a bulb check. When the engine is running, the voltage regulator deprives the blue wire of its ground.

If I were you I'd be looking for someplace around the burnt wire where there might have been a dead short. But I've got to admit that the voltage regulator has always been a mystery to me.
Back to top
View user's profile Send private message Gallery Classifieds Feedback
dagimp
Samba Member


Joined: July 30, 2008
Posts: 264
Location: Philly
dagimp is offline 

PostPosted: Thu Sep 06, 2018 8:53 am    Post subject: Re: Burning alternator warning light wire Reply with quote

Captain Spalding wrote:
Yep. The wire that goes to the generator is hot whenever the key is switched on. It get's power from the unfused side of fuse 1. It gets its ground from the voltage regulator (in this case the internal regulator in your alternator).

So when you turn the key to on, but haven't started the motor, power flows from fuse 1 to the gen light and then to ground through the voltage regulator. This is for the purpose of a bulb check. When the engine is running, the voltage regulator deprives the blue wire of its ground.

If I were you I'd be looking for someplace around the burnt wire where there might have been a dead short. But I've got to admit that the voltage regulator has always been a mystery to me.


Thanks Cap. I was wondering whether the short could be at the brake warning light. That blue wire is connected to the warning light and the warning light has always been loose. I suppose if that contacted the metal part of the dash, it could cause the short and wire melting. I'll check on that.
_________________
Buck

1973 Orange VW Thing, "Otto".
Back to top
View user's profile Send private message Gallery Classifieds Feedback
dagimp
Samba Member


Joined: July 30, 2008
Posts: 264
Location: Philly
dagimp is offline 

PostPosted: Wed Sep 12, 2018 7:48 am    Post subject: Re: Burning alternator warning light wire Reply with quote

Update: The only possible short I could find is that possibly the brake warning light could have been grounding on the metal dash. Otherwise, I couldn't find anything. I ordered a used wire from Mike at thingparts.com and it should arrive soon. Any suggestions/recommendations/tips on rewiring and soldering the new wire in behind the dash? Looks like the wire is melted until it goes into the big wire loom. So it has to be replaced from there to the generator idiot light to the brake warning light.
_________________
Buck

1973 Orange VW Thing, "Otto".
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Captain Spalding
Samba Member


Joined: February 19, 2005
Posts: 2483
Location: . . . in denial.
Captain Spalding is offline 

PostPosted: Tue Sep 18, 2018 4:17 pm    Post subject: Re: Burning alternator warning light wire Reply with quote

dagimp wrote:
Update: The only possible short I could find is that possibly the brake warning light could have been grounding on the metal dash. Otherwise, I couldn't find anything. I ordered a used wire from Mike at thingparts.com and it should arrive soon. Any suggestions/recommendations/tips on rewiring and soldering the new wire in behind the dash? Looks like the wire is melted until it goes into the big wire loom. So it has to be replaced from there to the generator idiot light to the brake warning light.

Seeing as you're not sure the cause has been identified and solved, before you permanently install the new (used) wire, you might consider making a temporary connection with some generic hook-up wire and an inline fuse holder with an 8 amp fuse. Just twist and tape the connections and then test.
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Display posts from previous:   
Reply to topic    Forum Index -> Thing/Type 181 All times are Mountain Standard Time/Pacific Daylight Savings Time
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

About | Help! | Advertise | Donate | Premium Membership | Privacy/Terms of Use | Contact Us | Site Map
Copyright © 1996-2018, Everett Barnes. All Rights Reserved.
Not affiliated with or sponsored by Volkswagen of America | Forum powered by phpBB