Flickering headlights

KARLITO626

MEMBER
2003 HONDA CIVIC
1.7L
4 CYL
2WD
MANUAL
240,000 MILES

I'm currently having a flickering light problem with my car listed above Ex. I was driving one night and noticed that my headlights were flickering so I decided to also turn on the interior light and it was also flickering. After awhile the flickering stopped and never occurred. Originally I thought that my alternator was failing so I decided to go to an auto shop and get it tested today but when I went everything checked out and the employee said that the tester said that my alternator, battery and starter is good. On my ride back home I decided to keep the interior lights on but it never flickered, not even once.

I have no clue on what is wrong.

1 Reply

STEVE W.

MECHANIC
13,015 POSTS

Flickering like that is commonly caused by a loose or corroded connection to the affected circuit. The flicker is the result of the difference in the resistance in the connection. Likely the vibration of the engine coupled with the voltage spiking at the connection cleared the issue. It could return at any time however. The hard part is to find the connection that is at fault. In this case I would look at the ground #401. It grounds the light switch and the interior lights If it were getting bad it could cause flickering as it would be turning the lights on/off. I would also check the battery connections at both ends and the grounds at the engine as those could also cause it and not effect the engine because they were not lasting long enough.
The ground I am referring to is under the dash near the lower area below the steering column.

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