Headlights blink on and off

[Rat Race]

I put 100 watt H4 bulbs in my 67 coupe, and now every time I put the lights on , they work for about 10 minutes and then just blink on and off.

Is the bulb too high a wattage or is is something to do with the switch?

 

[thehueypilot]

I put 100 watt H4 bulbs in my 67 coupe, and now every time I put the lights on , they work for about 10 minutes and then just blink on and off.

Is the bulb too high a wattage or is is something to do with the switch?

It's the dimmer foot switch. It was not designed to handle double the amperage that your new lights are pulling. Painless Wiring makes a relay wiring harness that plugs into the existing connections which was designed just for this issue. I had the same issue and I can tell you it was scary the first time it happened on a dark country road. I put the new harness on and it has not done it since.

 

[grego37]

ditto.
you need to run a relay, or you may have problems

 

[SuperDave]

Also consider:

Agree with the above but would NOT overlook the possibility that the lights are not GROUNDED properly. I would check that first.

 

[Loup-garou]

I put 100 watt H4 bulbs in my 67 coupe, and now every time I put the lights on , they work for about 10 minutes and then just blink on and off.

Is the bulb too high a wattage or is is something to do with the switch?

It's usually the headlight switch in the dashboard. There's a circuit breaker in there that often cuts out when halogen lamps are installed. The blinking is caused by the switch cooling a bit and the circuit breaker resetting, which happens repeatedly.

Some people swap in the switch from a '69 Mustang, which has a stouter circuit breaker to accomodate the quad lamps unique to that year. However, if you're going to run overwattage H4 bulbs, skip that idea and go straight to the relays. If you don't like fooling with wiring, Painless makes an H4 Halogen adapter harness which just plugs into one of your existing headlight sockets.

 

[chepsk8]

Super Dave!!!

You're back!

 

[danewers]

definitely the actual headlight switch in the dash. i had the exact same problem when i got my 100watt h4's. went down to the local mustang parts house and got a new switch, havent had the problem since.

 

[SuperDave]

Cheapie!

Yeah, dropped in before going on a fishing trip. Waiting for my buddy to arrive.

The Mustang is doing well and has placed in several shows this summer. Not bad for a car that was done TWENTY FIVE years ago! The "timeless wisdoms" flourish!

This forum hasn't changed much over the years. Big "go fast" ideas, no experience, no money, no skill, yahda yahda....... Good that we "vetrans" are around to temper the testosterone with injections of reality!

 

[pabear89]

This forum hasn't changed much over the years. Big "go fast" ideas, no experience, no money, no skill, yahda yahda....... Good that we "vetrans" are around to temper the testosterone with injections of reality!




SD's Timeless wisdom still rocks....................

Glad to see your still out and about,
Hook a big fish for dinner,
We bears like Fish!

PB

 

[Rat Race]

Just want to get back to the subject here,...

What kind of relay do i get, and where do i get it?


How does it go in and where?

Does the painless wiring thing have a relay built in?

Thanks again, sucks having to leave shows at 8pm

 

[thehueypilot]

The harness from Painless Wiring comes with the relay. I went to the Painless Wiring web site to get the part number for my Mustang and ordered it from Summit Racing about three years ago. I think it was around $75.

 

[ericl]

Here is a related topc

http://forums.stangnet.com/showthread.php?t=549113