Cougar6

For my 1987 560SL. My Low Beam Headlights were not working and my troubleshooting led back to the switch. So, I decided to take a chance and replaced the Combination Switch (the switch that changes from high-beam to low-beam, turn signals, etc., commonly called the "Turn Signal Switch/Lever" in Alabama). When I pulled the old Switch off, I must admit, it looked pretty rough. But, it did have daily use during the 23 years the car was my daily driver, so it was "honest wear".

There are a lot of instruction/tips on how to remove the Switch, so I won't reiterate them here. I will give you my experience:
1. I removed the Steering Wheel to give me easier access to the Switch and connection under the dash.
2. Disconnect the Negative battery terminal to protect the air bag.
3. There are two hex screws on the back of the Steering Wheel you need to remove in order to remove the air bag. Remember, you are unscrewing them by reaching around the back (Lefty-Loosey, Righty-Tighty), so the direction you turn is also "backwards". I made a bonehead mistake when screwing them back in, to turn them "to the right" which actually "was to the left" since I was reaching around behind the Wheel. It took me 15 minutes of frustrating "turning" before I realized I was loosening the bolts instead of tightening (screwing them in) them. Don't be like me!
4. When you get to the old Combination Switch you will find that there are two wires, one Brown and one Black that connect to the sides of the Switch with metal-screw contacts. Unscrew the connectors and pull the wires out. The Black wire is Ground and the Brown wire is Power. Remember which wire is on top and bottom.
5. Under the dash, the "female" end of the connector (the one the connector at the end of the Combo Switch wiring) is mounted to a metal bracket. The female connector is held on the bracket by plastic molding on the back of the connector (you can't see it). You free the Female Connector by sliding it slightly left or right to release it from the metal bracket. I released the Female connector from the bracket while it was still connected to the male connector. This made it much easier to then separate the male connector from the female connector.

Now for the BAD NEWS... My High/Low Beams work, but the Turn Signals are not working properly.
The Left Turn Signal is "dead" and the Right Turn Signal has "fast blink".

I'm thinking the problem might be a loose/bad ground or perhaps I connected the Black Ground and Brown Power wires connected backwards? Or don't have a good connection with the Ground wire?

The Pictures I have from the Web (Pelican Parts) show the Black wire on the "bottom" of the Switch and the Brown on the "top" of the Switch. Does anyone know if this is correct? The wiring diagram I have for the 560 isn't specific about this connection.

Any suggestions? Any suggestions on how the troubleshoot a ground problem?

I plan to troubleshoot on Friday, when I had time. Can I just switch the Brown and Black wires to see if that fixes the problem? Thanks!

Here is a picture that shows where the Black and Brown wires connected on the old Switch. Again, I connected the Brown wire to the top and the Black wire to the bottom.

myway

Brown is ground