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https://youtu.be/yw48gKmsy-0?si=lCyRCIn_OHqX-WkD
- Mikerowechips
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                10 months 3 days ago                #74967
        by Mikerowechips
    
    
            
            
            
            
            
                                
    
                                                
    
        https://youtu.be/yw48gKmsy-0?si=lCyRCIn_OHqX-WkD was created by Mikerowechips            
    
        Hello, new member here with a question about the video in the subject line. How do you determine whether there is a short in the primary or secondary windings based on a current ramp waveform? Paul suggested I create a thread to discuss it and share some data. Thank you!    
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- Tyler
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                10 months 3 days ago                #74969
        by Tyler
    
    
 	
					
                    	
            			
							    
    
            
            
            
            
                                
    
                                                
    
        Replied by Tyler on topic https://youtu.be/yw48gKmsy-0?si=lCyRCIn_OHqX-WkD            
    
        Hey Mikerowechips! I took this example of a shorted secondary winding off a 2009 Nissan Altima 2.5L:
 
You're looking for the abrupt start to the ramp, along with the missing turn-on oscillation. Beware that a waveform like this does not condemn an ignition coil by itself. Secondary includes the coil boot/wire and spark plug. A short to ground anywhere along the secondary will produce that waveform.
Also know that some coils just don't generate a visible coil turn-on oscillation, or the oscillation may be very difficult to view depending on your scope. A missing turn-on oscillation is not necessarily a red flag.
I didn't have any primary winding short waveforms on hand, so I borrowed one from an older SD video:
 
You're looking for the super tall ramp. The shorted primary will draw significantly more current than a known good. Again, beware, just because one coil draws more current than another doesn't mean a primary is shorted. I've seen more than once when a vehicle owner intermixed coil brands on an engine. As a result, the peak coil current draw varied by several amps.
    You're looking for the abrupt start to the ramp, along with the missing turn-on oscillation. Beware that a waveform like this does not condemn an ignition coil by itself. Secondary includes the coil boot/wire and spark plug. A short to ground anywhere along the secondary will produce that waveform.
Also know that some coils just don't generate a visible coil turn-on oscillation, or the oscillation may be very difficult to view depending on your scope. A missing turn-on oscillation is not necessarily a red flag.
I didn't have any primary winding short waveforms on hand, so I borrowed one from an older SD video:
You're looking for the super tall ramp. The shorted primary will draw significantly more current than a known good. Again, beware, just because one coil draws more current than another doesn't mean a primary is shorted. I've seen more than once when a vehicle owner intermixed coil brands on an engine. As a result, the peak coil current draw varied by several amps.
        The following user(s) said Thank You: Mikerowechips     
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- Mikerowechips
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                10 months 1 day ago                #75533
        by Mikerowechips
    
    
            
            
            
            
            
                                
    
                                                
    
        Replied by Mikerowechips on topic https://youtu.be/yw48gKmsy-0?si=lCyRCIn_OHqX-WkD            
    
        Ok, thank you for explaining that. I think I understand what I'm looking at now. I will set up some experiments to fully understand the theory.    
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