High and low beam headlights not working properly

2002 MAZDA PROTEGE
85,000 MILES • 2.0L • 4 CYL • 2WD
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JJAYMECH
  • MEMBER
  • 14 POSTS
On low beam driver side okay, but passenger side nothing. On high beam driver side okay, but passenger side dim. Also on high beam the low beam filaments glow slightly. Could it be a poor ground connection? Do you have a wiring diagram for the headlight circuit? I can do voltage checks? A harness diagram would really help.
Oct 22, 2019 at 6:16 PM
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JACOBANDNICKOLAS
  • ✓Experienced Mechanic
  • 110,246 POSTS
Welcome to 2CarPros.

If you have one of the elements dimly glowing, it is most likely a bad ground causing power to back feed through the light.

I attached schematics below. There are two different conditions, with DRL and without. Now, to make them readable, I had to break each one into parts. The first three pics are without DRL. I overlapped them so you can follow them

Pictures 4 through 6 are with DRL.

Let me know if this is what you needed.

Joe
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Professional Diagram for 2CarPros Members
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Professional Diagram for 2CarPros Members
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Professional Diagram for 2CarPros Members
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Oct 23, 2019 at 1:14 PM
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