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Passenger side headlight looses voltage under load

txagemtp

By txagemtp
in Troubleshooting & Recalls

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txagemtp Enthusiast

txagemtp

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2014 Silverado factory halogen headlights.  Noticed today my passenger side headlight did not work.  Driver side low and DRL work, as well as High beams and fog lamps. Tried replacing bulb and still did not work.  Verified new bulb was not burned out by bench testing and it worked without issue.  Went to headlight plug and tested and got 12v. Upon installing the bulb and turning on truck still no light output and metered again and reading of 2v. Wondering if BCM is going out on that side as I cant see any corrosion on terminals or burned wires.  Any ideas or helpful insight?? 

txagemtp Enthusiast

txagemtp

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Problem solved: The factory harness had some corrosion inside of it causing the issue.  So after depinning and making jumpers I now have working low beam.  Anyone know some place I can order a factory replacement connector and terminal spades? The one coming from engine bay?

 

tbarn Senior Enthusiast

tbarn

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FYI, corrosion causing low voltage/amperage is an open or partialy open circuit. Not a short.?

txagemtp Enthusiast

txagemtp

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tbarn, thanks for your unpearled wisdom. However by definition it is considered a short circuit. There are different kinds as you mentioned, but in general terms it is a short circuit.  See definition below. 

 

Short circuit — In a device, an electrical circuit of lower resistance than that of a normal circuit, typically resulting from the unintended contact of components and consequent accidental diversion of the current.

 

 

tbarn Senior Enthusiast

tbarn

Posted
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2 hours ago, txagemtp said:

tbarn, thanks for your unpearled wisdom. However by definition it is considered a short circuit. There are different kinds as you mentioned, but in general terms it is a short circuit.  See definition below. 

 

Short circuit — In a device, an electrical circuit of lower resistance than that of a normal circuit, typically resulting from the unintended contact of components and consequent accidental diversion of the current.

 

 

How does lower resistance drop you from 12v to 2v? I didn't see what you had going on but by your description, you had corrosion somewhere under the hood or front end.  Now, corrosion can cause many issues including high resistance (by far the most common) and shorts to other wires/terminals. With no other issues a short to other wires is unlikely. Short to ground would likely blow a fuse or melt wiring. So with only a headlight issue, low voltage at said headlight and your statement of corrosion it seems to me you have HIGH resistance, not low.

txagemtp Enthusiast

txagemtp

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1 hour ago, tbarn said:

How does lower resistance drop you from 12v to 2v? I didn't see what you had going on but by your description, you had corrosion somewhere under the hood or front end.  Now, corrosion can cause many issues including high resistance (by far the most common) and shorts to other wires/terminals. With no other issues a short to other wires is unlikely. Short to ground would likely blow a fuse or melt wiring. So with only a headlight issue, low voltage at said headlight and your statement of corrosion it seems to me you have HIGH resistance, not low.

Never said anything about resistance in the issue I was experiencing, I was merely correcting your misunderstood definition about a short vs open circuit. We can continue this where I prove you inadequate in your knowledge base. Or we can move forward and get back to a source for a new factory headlight harness plug and pins.

 

 

tbarn, have a good night and if you dont have anything of value to contribute then stop while you are ahead.

 

 

 

MODS please close/lock this thread.

 

 

tbarn Senior Enthusiast

tbarn

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Exactly what do you think corrosion does? Causes HIGH resistance! Hence 2v.

txagemtp Enthusiast

txagemtp

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3 minutes ago, tbarn said:

Exactly what do you think corrosion does? Causes HIGH resistance! Hence 2v.

Congratulations sir.  I applaud your basic electrical understanding.  

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