Signal lights

SWEETIE1965

MEMBER
1994 CHEVROLET SILVERADO
4.3L
4 CYL
2WD
AUTOMATIC
260,000 MILES

The left turn signal blinks real fast. The right turn signal blinks normal. I have changed both signal light bulbs(front and back) and I have changed the circuit board. All other lights work properly as far as I can see. This has me puzzled? I can hear the flasher come on when signal is turned on. Front and rear signal blink at same time when powered on. What can cause this?

Friday, September 21st, 2018 AT 12:57 PM

7 Replies

DANNY L

MECHANIC
5,648 POSTS

Hello, I am Danny.

Quick question. Have you by chance converted any bulbs to LED?
Thanks for using 2CarPros.
Danny-

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Friday, September 21st, 2018 AT 1:11 PM

SWEETIE1965

MEMBER
165 POSTS

No, I have not converted any bulbs at all.

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Friday, September 21st, 2018 AT 1:15 PM

DANNY L

MECHANIC
5,648 POSTS

Hello again.

Okay, on the affected side I would check all the grounds. Hope this helps and thanks for using 2CarPros.
Danny-

https://www.2carpros.com/articles/how-to-check-wiring

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Friday, September 21st, 2018 AT 1:48 PM

SWEETIE1965

MEMBER
165 POSTS
1994 CHEVROLET SILVERADO
4.3L
V6
2WD
AUTOMATIC
255,000 MILES

I have changed front and rear signal bulb and the circuit board. I can hear the flasher come on when signal is turned on. What can be doing this? Both sides of signal lights blink together when turned on.

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Saturday, September 22nd, 2018 AT 11:58 AM (Merged)

KEN L

MASTER CERTIFIED MECHANIC
51,746 POSTS

You are losing a ground or power somewhere. Here are the blinker wiring diagrams so you can test each circuit using the guide from above that Danny provided. Check out the diagrams (below). Please let us know what happens.

Cheers, Ken

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