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Old Nov 3, 2007 | 06:48 PM
  #1  
woodduck06's Avatar
woodduck06
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Default Electrical question:

I have a '75 Corvette. I was wondering if anybody could help me. All my dash lights, curtosy lights, and headlights dim whenever I step on the brakes, turn on the hi-beams, use my blinkers, basically anything that uses power. What would be causing this? Thank you for your help.



Bill
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Old Nov 3, 2007 | 07:36 PM
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Durango_Boy's Avatar
Durango_Boy
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From: Columbia Missouri
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Could be a bad ground at the battery, or even a bad POS connection. Also, drive by a parts store like Oreilly and have your battery and alternator tested.
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Old Nov 4, 2007 | 08:55 AM
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From: charlotte north carolina
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check the condition of the wires at the horn relay. all the electric power goes thru that one terminal. corrosion could cause a poor connection.
jeff
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Old Nov 4, 2007 | 09:15 AM
  #4  
...Roger...'s Avatar
...Roger...
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Originally Posted by Durango_boy
Could be a bad ground

Turn on your high beams and watch them on the wall of your garage.Go around and wiggle wiring connections and see when they get bright and that will be the spot.Dont forget to wiggle the bulkhead connector and the black 14 gage wire that connects and grounds down near the starter.Also move the 4 wire connector just behind the passenger head that goes to the starter.(I believe the 75 has that conn.)
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Old Nov 4, 2007 | 06:12 PM
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woodduck06
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Originally Posted by jnb5101
check the condition of the wires at the horn relay. all the electric power goes thru that one terminal. corrosion could cause a poor connection.
jeff


I rewired my whole car by using wiring diagrams. My diagrams don't show the power to the Horn Relay how you described it. Also, I used new wires and new terminals throughout the car so there won't be any corrosion.


Last edited by woodduck06; Nov 4, 2007 at 06:47 PM. Reason: improving
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Old Nov 4, 2007 | 07:22 PM
  #6  
I'm Batman's Avatar
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St. Jude Donor '07
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Is your horn relay a metal box under the hood or a plastic box under the dash?
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