[bookemdanno]

I have a 1965 Mustang 2+2 (289). When I turn my left turn indicator on my front left turn light flashes correctly. However both rear lights and my license plate light flash at the same time. All my bulbs (front and rear) and the flasher relay have been replaced. Do you think the turn indicator switch itself is at fault ?

[Veronica]

Hello. What do the rear lights do when you hit the right turn signal?
This might help.
The Care and Feeding of Ponies: Turn signals

[cushman350]

The license plate light indicates wiring issues.

[bookemdanno]

When I turn the right turn indicator on, both the right front and the right rear turn indicators flash correctly. No other lights flash as when I employ the left turn indicator. A fellow worker thinks I have a faulty turn indicator switch.

[rocky289]

Check the earth/ground at the L/Rear light

[Veronica]

Hi again. The tail lights/ turn signals use the body of the car for a ground. The ground wires that are attached to the mounting studs of the tail light housings are for the reverse lights. Any problem along the wiring of the tail light harness itself would make the problem work both ways, as in, if you hit one turn signal, they both start flashing. The same deal on the brake light wiring. There's only one wire coming through the brake light switch. The tail lights and license plate light is all powered by one wire. A problem as specific as what this car is doing would pretty much have to be in the turn signal switch.

[bookemdanno]

to you all. I have a turn indicator switch and a wiring diagram manual on order. I will replace the switch and also check all the required lighting grounds. Hopefully that will solve this problem. . There is a second situation that I believe is related to the light switch itself. The instrument panel lights are very dim even with the switch cranked to the highest intensity. And....with the light switch in the off position, I step on the brakes, and the instrument panel and rally pak lights come on. Any ideas ??

[Veronica]

Hi again. On that one, I think that I would start out with the headlight switch.

[KCodeK]

Just a thought.

I have seen this sort of thing happen when someone puts the wrong bulbs in one or more of the light sockets or insalls one wrong. These should have 1157 lights in all the turn signal and tail light sockets.