How do i fix my turn signal switch - 1996 Oldsmobile Cutlass Supreme Coupe

You replaced factory bulbs with led bulbs ? There is no relay BCM - body control module does it
Turn Signal Lamps
The body control module (BCM) is responsible for controlling the turn signals and hazard lamps. When the turn signal switch is placed in either the left turn or right turn position, the BCM receives a signal from the turn signal switch. The BCM then sends an on-off voltage signal to either the left or right turn signals and their instrument panel cluster (IPC) indicator. When the hazard switch is pressed, the BCM receives a signal from the hazard switch. The BCM then will send an on-off voltage signal to all the turn signal lamps. All the turn signal lamps will flash including both IPC turn signal indicators.

Put the stock lamps back . LED's won't work .

You say you replaced turn signal switch, Have you changed the relays for this? Also check chevy recalls as they have had several concerning electrical problems with these cars. The harness can also get corroded as well as the bulb sockets.

You replace the turn signal/multifunction switch.

Yes ,the plastic cancel peg on the left is broken ,right is close
to breaking also,only fix is a new turn signal switch,sorry.
should be about a 60.00 job ,plus the switch .another 60.00or so.

The hazard switch is also the device that supplies the turn signal "flash". If you continue to hear the noise of the turn signal flashing when the turn signals off than the problem is the turn signal switch. It is grounding The purple wire from the hazard switch which makes the hazard switch think the turn signal is on. The fix for this is to relace the turn signal/multi-function switch. Typically they will start to go bad in stages. Your symptom is the first stage. Eventually either the turn signals or the brake lights will also sto working. Let me know if you have any questions and I'll do my best to answer them. Thank you for using FixYa.com!

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I'd check your multi-function switch (on your steering column, what you touch to turn your turn signals on). There is a small metal clip on the base of it that tells your car to turn the turn signals on (right or left). Also trace the wires from the mulit-function switch to your turn signal relay and see if you're getting power when the switch is activated.

there's a little plastic piece inside the turn switch called a cancelling cam that broke or quit working. The only fix to get switch to return is replacing the turn signal switch. I don't think you can buy the part separately.

No the dash is the hazard light switch, it's also the turn signal flasher, dealer part only replace, replacing it will fix your problem. Feel the switch when you hear the clicking.

If you have a multi-function dimmer/turn signal switch: YES it will correct the problem.

You likely have a sticking hazard signal relay or hazard switch. Try turning on the left or right turn signal then depressing and releasing the hazard switch a few times. If the lights begin working you probably have / had a sticking switch. They don't get used often and this is not uncommon. Also could be relay. Thats a cheap fix and easy to locate. Should be with fuse box or near it.

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Brett