05-02-2021, 06:42 AM
			
			
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			#1
			
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				Alternator Wiring Question
			 
			 
			
		
		
		
			For I hope this isn't a duplicate post, I just posted it but it seems to have disappeared..maybe a hit preview.  Anyways, I'm trying to finish up the wiring on my swap and having trouble with the alternator.  I have the main power connected but I can't find a wiring diagram for the blue wire and the small red wire.  I believe the blue wire is for the voltage gauge but no idea on the small red wire.  Does anyone know where this goes?   
 
 
		 
		
		
		
		
		
		
			
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			05-02-2021, 01:31 PM
			
			
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			#2
			
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			Is that coming off the hot side?  I've never looked at our alternator but I've not seen a setup like that before.  Thats too small of a guage  to be the primary feed to the starter i would think.  Maybe someone added that to an accessory? Or it may feeds directly back to the dme to monitor output.  Sorry, I'm sure that's not much help but I'm interested in finding out.   
 
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			05-02-2021, 02:27 PM
			
			
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			#3
			
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			Per the Bently Electrical wiring diagrams EWD-54 that red wire feeds a 40amp Maxi fuse at Relay support 2. The Maxi fuse powers the relay and  SAI pump so you will just remove. The blue wire on EWD-15 is to the charge indicator (Voltage gauge) as you previously stated.
		 
		
		
		
		
		
		
		
		
			
				  
				
					
						Last edited by 911monty; 05-02-2021 at 04:04 PM.
					
					
				
			
		
		
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			05-02-2021, 02:40 PM
			
			
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			#4
			
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			Interested in this as well as where the big wire on the alt goes to (ultimately the battery obviously, but does it to to the junction at the top of the engine, toward the firewall?  Cable 19? 
So is the small red wire going to the 40amp maxi fuse or relay support 2?  2 very different things.
  
		 
		
		
		
		
		
		
			
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			05-02-2021, 03:58 PM
			
			
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			#5
			
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	Quote: 
	
	
		
			
				
					Originally Posted by  Stl-986
					 
				 
				Interested in this as well as where the big wire on the alt goes to (ultimately the battery obviously, but does it to to the junction at the top of the engine, toward the firewall?  Cable 19? 
So is the small red wire going to the 40amp maxi fuse or relay support 2?  2 very different things.
   
			
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" 
The small red wire goes to the 40amp maxi fuse. The "Case at relay support 2" is a description for location.  The large wire goes to terminal 30 at the firewall, then to the current distribution panel, then to battery.
		  
		
		
		
		
		
		
		
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			05-02-2021, 05:37 PM
			
			
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			#6
			
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			So it's a direct feed to the sai pump it looks like?  I guess that makes sense as you would want this powering up immediately if called for. 
 
Where did that diagram come from?  I am a bit confused why it makes mention of an egr circuit.  
 
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			05-02-2021, 05:41 PM
			
			
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			#7
			
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			came from the FSM
		 
		
		
		
		
		
		
			
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			05-03-2021, 03:28 PM
			
			
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			#8
			
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			awesome thanks guys, so it sounds like I only need to connect the large cable which goes to the battery and I'm all set.    
		 
		
		
		
		
		
		
			
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			05-03-2021, 03:30 PM
			
			
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			Well, you need the small red wire connected also.
		 
		
		
		
		
		
		
			
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			05-03-2021, 03:45 PM
			
			
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			#10
			
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	Quote: 
	
	
		
			
				
					Originally Posted by  truegearhead
					 
				 
				awesome thanks guys, so it sounds like I only need to connect the large cable which goes to the battery and I'm all set.     
			
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Yep!
 
	Quote: 
	
	
		
			
				
					Originally Posted by  Stl-986
					 
				 
				Well, you need the small red wire connected also. 
			
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No his Audi powerplant is far from stock and has no need for SAI. Maybe an airplane nav light   
		 
		
		
 
		
		
		
		
		
		
			
				  
				
					
						Last edited by 911monty; 05-03-2021 at 03:48 PM.
					
					
				
			
		
		
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