TURN SIGNAL AND BREAK LIGHT ISSUE

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My 72 vert is going together ok at this point but I have installed the tail lights and the turn signals only work if I work the handle by hand, they will blink fine if I do it by hand but don't work on there own, I replaced the blinker relay and still nothing, Also I have no break lights, all other lights work good. do you have any ideas as to what I can check?

 

midlife

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Brake lights: are the two spade leads attached to the circuit breaker that powers up the brakes and 4 way flasher? If so, perhaps the CB is bad.

 

Don C

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By saying you can work the flashers by hand, are you just looking at the dash indicator lights, or have you looked at both front and rear lights when the turn signal switch is activated?

Have you checked the bulbs, both front and rear?

Are the wires connected in the trunk?

The brake light circuitry also runs through the turn signal switch.

Are all of the underdash and firewall connectors connected?

Proper grounding from battery to chassis to engine?

 
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DON, When using turn signals by hand the turn signals all work at lights and dash indicators. these are all new bulbs through out. wires all seam to be connected at lights, as far a grounding goes I have a ground wire from battery to engine but I will have to check on the engine to chassis. as far as under dash connectors I believe everything seems fine except for the wires going to the two curtacy lights, also now that you mention it I don't remember seeing my instrument lights on either. I will have to check those tonight as well when I get home.could all these be connected?

 

Don C

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The battery ground cable runs from the battery to the bottom screw on the voltage regulator z then to the block. It's also a good idea to run a ground from the back of the engine to the firewall. Missing grounds will cause all kinds of issues as the electricity seeks a ground through other circuits.

 
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Hi 

This sounds like current is going to lamp directly from turn signal switch and not from the signal relay 

the turn signal switch should energize the relay, which has a small RC circuit in it to charge and discharge the coil-- this action provides the flash 

I wonder if it is a simple mix up of wiring - perhaps spade terminals going to the wrong contact - therefore bypassing the relay

 
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72 mustang convertible.351c 4v bored and stroked,roller cam and lifters,still in process of restoration
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just to fill everyone in on what the issue was on this, as I went through all the wiring I found that where the plug in on the steering column is, there were two of the wires pulled out of the plug in just a little. pushed them back in and all is well. Thanks to all for the replies and comments.

 
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