Turn Signal Issue
All info borrowed from HybridZ!
After spending much time searching threads and tracing wires, I thought I would post my findings on how the Hazard Switch and Turn Signal system works on my ’77 2+2. After learning how it works, it’s really not that complicated. The Hazard Switch is basically a double poled “On/On” switch. When the Hazards are turned OFF, the turn signals are turned ON (and vice/versa). When the Hazards are turned OFF, current still flows into the switch (from a switched hot power source), through the switch and supplies the Turn Signal system. When the Hazards are turned ON, it kills the current to the turn signals and a different power supply (constant hot) flows through the switch and supplies current to the Hazard system. This is why a bad Hazard switch can dork up the Turn Signals.
The hazard system current comes from the fuse box constant hot red/white wire, goes to one of the poles on the hazard flasher, out of the hazard flasher via green/blue wire to the hazard switch harness clip where it turns to green/white, then to the hazard switch, then out of the hazard switch as green/black (right side flashers) and green/red (left side flashers)….These wires stay the same color when passing through the harness clip.
The turn signal system starts with switch hot current (solid green wire), goes to the hazard switch harness clip, stays solid green when it passes through the clip, then goes to the other pole on the hazard switch. Current comes out of the hazard switch on the other solid green wire, goes to the harness clip and turns to green/ yellow, then goes to the turn signal flasher. It then goes out of the flasher via a solid white wire to the harness clip at the turn signal lever on the steering column. This wire turns solid green when it goes through the harness clip and is soldered onto the center of three wires on the back of the turn signal lever. When the lever is moved up or down, it sends current to either the top or bottom of these three wires white/black is left side turn signals (which turns to green/red when passing back through the harness clip), and white/red is right side turn signals (which turns to green/black when passing through the harness clip).
The third circuit that goes TO the hazard switch (but doesn’t actually go THROUGH the switch) is the little “Hazard” light (right below the switch) that illuminates when you turn on the headlights. Current goes to the light via the green/white wire that turns to red/ blue when passing through the hazard switch harness clip. Current goes through the bulb, and out through the black wire which turns to red/blue when passing back through the harness clip.
I’m not sure what year car this schematic came from, but the wire colors were exactly the same on my ’77, except that it doesn’t mention the changing colors when passing through the harnesses….I’m pretty sure my harnesses are all factory though.
I wish I would have taken pictures of my Hazard switch when I took it apart to clean. It was extremely simple though, and it works great now……There are 4 screws on the bottom of the switch. Remove them and pull off the cover. Be careful not to lose the spring that sits in the hole on the bottom side of the switch, or the piece of plastic on the end of the spring. From here, you can see the electrical contacts. The lever simply lifts off and is easily cleaned with a wire brush or similar.
Hope this prevents some headaches someday!
From another post:
After cleaning the hazard switch and the turn signal switch, my signals work great. I mentioned how I cleaned the hazard switch, but not the turn signal….and I’m pretty sure these are the only 2 moveable contacts in the system. If you look at the last picture in my original post you can see 2 phillips head screws (one above and one below the 3 wires). Remove those 2 screws and the brownish colored plate will come off. Inside there is a U-shaped contact that fits up inside the turn lever. Mine was so gunked-up that it didn’t even fall out, but be looking for it. I pulled the U-shaped contact out and cleaned it, along with the contacts on the inside part of the brown plate. It’s sort of hard to explain but makes perfect sense once you take the brown plate off. Basically one leg of the U-shaped contact sits between the green wire and the white/red wire, and the other leg sits between the green wire and white/black wire. When you move the turn lever up it connects the green wire and white/red wire (down connects the green wire and the white/black wire). It was not hard at all though…….the hardest part was the time it takes to get to the turn signal assembly, and get it removed.
Oh yeah, if you remove your turn signal assembly, it would be a good time to clean and WD40 the springs under the arrows, and make sure the ears that are hashed in red move freely and return to their original spot. These ears are what returns the turn signal lever back to off when you turn the steering wheel back to center.
REBUILDING AN S30 turn signal SWITCH
The turn signal switch is a common point of failure. It contains several tiny parts, and the front face of the switch is open, allowing contaminants to get into the switch itself. Most often, the contact points corrode, causing an open circuit when the turn signal lever is engaged.
To refresh your turn signal switch, take off the steering column cover by removing the 6 screws on its underside. Next, separate the two halves of the steering column controls, which are the combination switch (lights, wipers) and the turn signal switch (blinkers and brights). These two halves separate from side to side by removing two screws on the top and bottom of the column, accessed from the outboard (left) side.
Once the halves are separated, take a look at your wires. After almost 40 years, most of our Z’s have had one or more rounds of hack artists mess with our wiring harnesses. What the manual says may not be what exists on your car. Protect yourself from pain later by using masking tape to label both ends of all wires before you unplug them. You can leave your combination switch attached, so don’t worry about those wires.
With the switch removed from the car, go to a clean work area. Do not perform this work over carpet, as you run the risk of losing the internal fiddly bits forever. I believe an OEM unit runs about $250 right now, and the wiring harnesses differ from year to year, so this is not worth taking a chance. At the base of the signal arm there is a crescent-shaped brass colored switch housing with three wires leading into the back PC board.
Hold the assembly face down, so that the board and wires are facing upward. Gently pry the three retainer tabs up, so that you can withdraw the board. A little BB and a rocker plate will probably fall down into the switch housing – this is why you held it face down. Better in the housing than rolling across the table and into oblivion! Dump them out into a little cup and inspect the switch internals.
It probably looks dirty and corroded, or at least heavily oxidized. A little contact cleaner and a wire brush will brighten it right up. Once everything is clean, dab a little dielectric grease in there to help avoid corrosion in the future.
To reassemble the switch, place the little BB on top of the spring in the switch housing. Put a dab of the grease in between the forks on the wired board, and place the rocker plate on top of it. The grease will help the plate stay in place until you sandwich into position on top of the BB. Gently lower the back into position on the housing, keep it squeezed shut, and give the arm a few throws and make sure everything is moving smoothly. Shake the assembly and listen for your BB – if you got it wrong, the BB will be rattling around in there. If you are confident you have it right, bend the retaining tabs back into position.
Mount it back up and hopefully you have some working turn signals!
And last but not least, some more info….
