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Topic: lighting prob. (Read 937 times) previous topic - next topic

lighting prob.

ok i have an 85 cougar ls and everytime i turn my headlights on i lose my dash and tailights my speedo still works but nothing else does in the dash i still have turn signals and brake lights but when i turn the high beams on my lights just start flashing i have replaced the switch and it didnt help at all does anyone have any idea's thanks

lighting prob.

Reply #2 –
ok i have an 85 cougar ls and everytime i turn my headlights on i lose my dash and tailights. My speedo still works, but none of my other instruments light up.  i still have turn signals and brake lights. But when i turn the high beams on my lights just start flashing. I have replaced the switch and it didnt help at all. Does anyone have any idea's thanks.

Hope this is more readable.

lighting prob.

Reply #4 –
no thats what i dont get. i have headlights but not brights. i can run my dims with no prob, but my taillights just wont come on

lighting prob.

Reply #5 –
Trinom asked if your front side markers came on. You did not answer the question. Details are important when trying to buttstuffyze electrical problems.

Is the car's wiring stock?
Are all the lights stock?
Did the problem occur after you did some work on the car?
Do you have a test light or a volt meter for troubleshooting electrical problems?

There may not be one answer to all your problems.

The headlights are flashing on high beams because the circuit breaker in the headlight switch is opening and closing. There is an electrical overload causing the breaker to heat-up and open. Then it cools and closes.
Are all four headlights flashing? If not try unplugging the one that is not flashing.

lighting prob.

Reply #6 –
I have a similar problem, All my lights, (tail lights, marker lights, turn signal and brake lights, high and low beams etc) worked two days ago, then after I  hooked up the speaker wires that were laying on the floor spliced but not connected from the last owner, I turned the car on to leave, the instrument panel would not work.

This is a 86 cougar btw.

So my friend replaced two fuses that went out and everything seemed to work and even the clock and  under dash lights came on, but when it got dusk out I turned the headlights on and the panels went out. Now they will not work at the same time.

The marker lights glow when the headlights are on and they go out when I turn them off, the tail lights also come on with the headlights. 

They do not flash like the above person and  everything on the car is pretty much stock. 

I have a test light but not sure what to test never used one before.

Any ideas?

9:49 pm
Was hoping for some ideas
86" Cougar 5.0 V8

lighting prob.

Reply #7 –
all the wiring in my car is stock. im unsure if the marker lights work to be honest ive never looked at them. i can make my all my lights work by putting the switch in between the running light and headlight spots, but it over loads the breaker and they flash. the only thing i have done to the lights is put silverstars in for my dims. hope this helps

lighting prob.

Reply #8 –
Here are the wiring diagrams. The headlamps have indipendent circuit and the rest of lights too. One extra question - does your car have automatic lamps & headlamp dimmer? This wiring diagram is for cars without these features. If yes, I'll post another wiring diagram.



First, I would solve the tail lights issue.
Do you have some multimeter or self powered light? It really looks like the main switch, because this is the ONLY point of connection of these two circuits (front and other lamps). If you put this switch out, control the conection between pins A and R. If you have the switch out and look from the back you will see nine pins. Eight pins are horizontally and one (the right bottom) is vertical. A is bottom center pin and R is central pin. They should have connection in all cases except off. Is it right?