VW Dash Switch Testing - Turn Signal Switch:

Video Transcript:

Hi! Sam here with JBugs.com We're going to go over testing some of the electrical components and switches for our car, before we install them, along with our new wiring harness. Switch Overview In this video, we're going to be testing a new turn signal switch as the original switch for our 1971 Super Beetle had a broken cancellation mechanism. We've replaced it with this aftermarket unit that we'll test here at the bench, like we've done with all of our other switches. Here, we can check the operation of the turn signal cancellation. When the turn signal lever is moved to one side or the other, a small tab pops out at the opposite side of the switch. The cancelling ring, on the back side of the steering wheel, brushes against the tab and when the wheel turns the opposite direction, it moves the lever back to the off position. The turn signal switch is also part of the wiring for the horn, through the contact here on the face. It also operates the headlight relay, toggling back and forth between the low beams and the high beams, when you pull back on the lever. Looking at the back of the switch, we can see the various wires. On one side of the switch we have a brown, a white, and a white and brown wire. These are all ground circuit wires and looking where the wires attach on the switch, we can see the white wire connects to the contact ring for our horn. This will hook up to the horn ground wire in the front left wiring harness. The brown and white wire is attached to the lower contact for the headlight relay and will connect to the S terminal on it. The solid brown wire is the chassis ground for the headlight relay switch and will ground out to the body inside the trunk. On the opposite side of the switch, we have five more wires. Originally, the switch would only have three wires but as this is an aftermarket switch, it has some additional wires that we won't be using. We pull all of the wires out and away from the switch so we can go over the wires that we will and won't be using. On the outer terminals of the switch, we have three wires that we will be using and on the inner terminals, we have two more wires. On this particular switch, the wires are red and black, and grey. There is also a small jumper wire that connects to the terminals. None of these wires will be used. We will be using the black and green, the black, and the black and white wires. The black and white left turn signal output, and the black and green right turn signal wires follow the factory color coding. The black input wire at the center is originally black, white, and green but on most aftermarket switches, it's just going to be black. Testing The black wire at the center terminal is power in to the switch from the flasher relay. As our switch is currently positioned, the lower terminal is power out to the right side, the upper terminal is power out to the left. We'll test our new switch to demonstrate how you can check your switch at home, using a multimeter set to test continuity with an audible beep. With the switch at the off position, we use one lead to represent power in to the center terminal on the switch and we check the continuity, or power out, at the remaining terminals. We don't have power at any of the other terminals, and shouldn't. If we did, that would mean that our switch has a short in it and would need to be repaired or replaced. Next, we turn the lever to the right position, moving the lever up and now check for power at the black/green wire. The duplicate terminals on the switch work the same way, power would come into the center one and out of the bottom one. Keep that in mind if you have an issue with your switch. You may be able to just move the wiring to the duplicate terminals and have a working switch again. Moving the turn signal lever to the left position, we check the terminals again at the black/white, left turn signal terminal, and at the inner terminals. Everything works but as we mentioned, the wires at the inner terminals will be removed. We only need the three wires from the outer terminals here and the three wires from the opposite side of the switch. While we're testing, we'll double check the momentary ground when we pull back on the lever for the headlight relay, by checking the brown and the brown/white wire for continuity. With leads to each wire, there is no connection but as we pull back on the lever, we have continuity. Finally, we'll check that the horn contact ring on the face of the switch has a good connection with the white wire. With that, we've confirmed that our new switch works and is ready to install. We'll finish with the mention that the back side of all 1968 and later turn signal switches are primarily set up the same as this. Later 1971 switches have a built in conduit for the wiring but the mechanism and the terminals for 1968 all the way through 1979 is going to be roughly the same and can be tested similarly.