I’ve got an 1984 Chevy Suburban that when I put the Left Tun Signal on, All of the signals Flash (altho the Right side is weaker)
The Right Turn Signals are working OK.
Brake and Tail lights are Normal
Are some wires melted together someplace?
I am at a loss as to where to start looking for the problem
Time to look at replacing the control mechanism in the steering column. If you have tilt control on the steering wheel try it at different settings and see if that makes a difference. One of my work trucks the left turn would not work when the steering wheel was tilted all the way down, don’t tilt it all the way down and I can live with that.
Try cycling the emergency flasher switch a few times to see if that changes things.
I’m thinking multifunction switch (turn signal, cruise control, etc) also. Try spraying some CRC Electrical Contact Cleaner into the base of the switch at the steering column. This got the switch working for a few more days on my 2000 Blazer. It didn’t fix the problem but the cleaner confirmed the switch was bad.
Ed
Did you recently replace any turn signal bulbs? Putting a single contact bulb in place of a double contact bulb can do this. Of course I have no idea if a 84 Chevy has the old style bulbs.
@oldtimer11, an '84 should have those older ‘offset’ lug style dual filament bulbs. And, one could be in wrong or the wrong type, like a single filament in a dual filament socket.
Check the grounds on the left side including wiring, sockets and bulbs.
What I would try is taking a new replacement lamp and one at a time replacing each of the lamps starting on the left side. If changing the lamp does not fix put the old lamp back. Also look in the sockets for corrosion or any foreign matter.
I’ve seen detective lamps do this as well as wires and sockets.
Rgds IGN
Natog is on to something. A bulb can be defective internally, bridging the taillight and brake/turn signal circuits.