MG Car Repair: 1968 MGB turn signals, turn signal switch, voltage stabilizer

Question
My turn signals stopped working.  I have checked the fuses, inline fuse to the flasher unit, all bulbs and even bought a new flasher unit with no luck.   Any suggestions before taking it into my gut to have it worked on?


Answer
Hi Steven,
Go to the flasher unit and with a test light or volt meter, test the green wire for power with the key on. This will confirm that you have power from the instrument voltage stabilizer. If you didn't than your fuel gauge would not work.

Next take your 12v test light and test the other pin on the flasher while the green wire is connected. The test light should light and maybe even flash. This tests the flasher itself. (new can be bad too)

Next go to the turn signal switch and test the light green wire before the plug connecter. This confirms that the power is going through the flasher and wiring to the turn signal switch. Then check the other side of the plug connecter for power. (the color of the wire may or may not be the same)

If all is well up to that point check the green with a white tracer and green with a red tracer alternately when you turn the switch back and forth. Check it on the car harness side of the plug connecter. This confirms power is going through the switch.

If you have power up to that point you have either a problem at the lights or the wiring in between the lights and the switch.
Let me know,
Howard