My better half has a 69 XR-7 convertible that has suddenly developed a problem with the turn signals.
When you put the signal on for a right turn it blows the fuse that runs the signals, back-up lights, emergency lights, and radio. The Left signal works just fine and everything else keeps working.
The car has tilt-away steering. The brake lights, the tail and marker lights work fine.
I am trying to figure this out as she would like to use her signals when driving the car, instead of sticking her arm and hand out the window and gesticulating to other drivers.
Anyone have any solution?
That sounds to me as a short that could be anywhere from the switch to the front/rear lights, including sequencer for the rear.
Disconnect the Red plug at the sequencer in the trunk and put the turn signal in the right mode. This should power the front right light as well as the right rear inner light. If it doesn’t blow the fuse then the problem lies in either the sequencer or the turn signal switch.
You can try to bypass the switch by providing a fused power source to circuits 445 and 449 at the turn signal harness and see if the front and rear right lights illuminate without blowing the fuse.
Next, test the sequencer by providing power again at circuits 445 and 449 at the sequencer. Note, Only the middle and outer right taillights will illuminate.
If all of the above goes well, but you still have a problem, it is most likely that the turn signal switch is shorting out.
Coach Jack
Thanks for the great suggestions.
Coach Jack, you have some very specific ones. I don’t suppose you have a diagram of which circuits are which of the turn signal harness and sequencer?
I did buy a new tilt turn signal switch.
Thanks for all the help.
The diagram of the plugs are from the 1969 Mustang and Cougar Electrical Drawings pages 2-E20 and 2-E21
445 - Orange-Blue
449 - White-Blue
The first attachment is the Turn signal harness on the vehicle side
The second attachment is the connector to the sequential box. The connector on the left is the input to the box and the lower connector is the output. Note the output of the sequential box only affects the middle and outer lights. The middle right light is 446 Orange-White and the right outer light is 447 Orange-Red.
[attachment=1]69 SEQ Circuits.jpg[/attachment]
[attachment=1]69 SEQ Circuits.jpg[/attachment]
Let me know if you need any additional information
Coach Jack
Started looking into the wiring from the switch… OMG what a dog’s breakfast. Someone has cobbled the wiring together very badly. We were able to fix a bad wire and everything is working again. At some point it will all be fixed properly, but not today.
She can now get her car to the show we are going to on Sunday without fear of a ticket |(at least for no signals).
Thanks very much Coach Jack.