More then likely it needs to be replaced, if its the actual signal inside the car, turn it on check outside the car which one it is and replace!!
Bad flasher unit or turn signal switch
Where is the backup light switch on a 2002 buick century?
If a turn signal does not blink on a 1996 Honda Accord that it is time for it to be changed. To change the bulb and locate the light housing and remove the older light. Replace the light.
If you turn on your 1999 mustang v6 car and the right signal light stays on and doesn't blink and you switch the car off and then the left signal light stays on without blinking, then you need to see a mechanic.
this may be a bad groun on the light ficture itself check the contacts on the light socket .. it could also be a faulty light
The 2001 Buick Century brake light switch is located beneath the dashboard, on the drivers side. The brake light switch should be labeled as such.
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Check the back signal light. Usually if the front blinks fast the back is out or need to be replace. Vice versa
It looks like your left front one is burnt out. When there is not enough current flow the good light will not flash.
Change the front turn signal light bulb. It's bad.
When the trac light is off, on a Buick Century, the traction control monitoring system is disengaged. It is recommended to have the trac system engaged on wet roads.
1995 Buick Century turn signal light bulb replacement: Purchase the correct replacement turn signal light bulb(s) first, before disassembling the vehicle. See sources and related links below for replacement bulb information. Then consult your owner's manual for the turn signal light bulb replacement procedure. As simple as it sounds, the owner's manual is the best place to start for bulb replacement instructions and illustrations. You may want to consider replacing both left and right at the same time in order to keep brightness and color equal (optional).