Turn signals

[samanthasue2002]

The hazard lights work, but neither side signals work. We pulled apart the signal switch to trouble shoot. It doesn't really match any of the diagrams in the Haynes manual. The car is a 76 manual shift 2002. There are 6 wires on the back of the switch. The blue/black goes to the right side blinker, the blue/red goes to the left side. The green/yellow goes back to the hazard light switch. There are 3 other wires. Yellow, white and green. The green is hot when the ignition is on. The white has power when the brights are on, and the yellow has power when the lights are switched on. So my guess is that the yellow and white are not related to the signal light problem. Does anyone have an accurate wiring diagram for a 1976 2002? Where is the power source for the signals? Where should we look next? Also, when we jump wire power from the green to each side (blue/black and blue/red), the signals light up. When we jump to the green/yellow, only the left side lights up. Any help would be appreciated.

[Kidasters]

One thing to consider - the lights ground to the body. Therefore, things only work "right" when you have the turn signal housing grounded to the body. This normally happens when it is attached. So - if you are trying to troubleshoot these with the housings out, you'll have issues.

[samanthasdad]

So if I ground the switch housing while I trouble shoot it, I should be better able to figure out the problem,right?

What I'm wondering, is where is the power source for the signal lights? The blue/black and blue/red run to the lights themselves. I figured out that much. The white and yellow wires are involved with the headlights/dinner switch operations. The green wire has power when ignition is switched on. Does the power that operates the signals come through the hazard light switch? Or is there an internal connection between the green wire and blue/red &blue black terminals? There is a green/yellow wire that is between the blue/red and blue/black wires. I haven't traced it ocmpletely, but there is a green/yellow wire that connects to the hazard light switch. Even with the switch assembly hanging loose, when I turn on the hazards,all four flash, and power is routed through the system. The car has the 12 fuse system. The only wiring diagrams in my Haynes "Book of Lies" is very hard to follow. Printed in some sort of micro print. IF someone could post a legible 12 fuse diagram, it would help.

[Scott Sislane]

So if I ground the switch housing while I trouble shoot it, I should be better able to figure out the problem,right?

the signal housings need to be grounded, or the bulbs won't have ground, just (+). If you just leave them attached, you'll be good for trouble shooting. I have a 76 but not familiar with the wiring colors...sorry.

[samanthasdad]

The lights are all still connected,and when I run power to the blue/black and blue/red wires the respective side signals will light up. They will also flash when I turn on the hazard lights.

[Scott Sislane]

I found this helpful when I was running through wiring a while back:

1976 BMW 2002usa Wiring Diagram-1.pdf

[02for2]

The stock turn signals are dual purpose. Running lights/Turn Indicators. They use dual-filament bulbs to accomplish this.

Both wires coming through the fender to the light fixture are hot (+) - 1 for the Running Lights and 1 for the Turn Indicators.

As mentioned, you need to ground the fixtures to the body to complete the necessary circuits.

To distinguish which wire is which, attach a DMM to one of the wires and ground it to the body. Use the headlight switch and Turn Indicator switch to determine which is which.

This also explains the 'extra' wiring you're talking about.

Cheers!

[samanthasdad]

Thanks. You guys are a huge help. These forums are the best thing to ever happen to the "car hobby".