dibbons
Well-Known Member
I have low beam, but when pressing the floor switch for high beam the headlights go out and the ammeter goes to full discharge. I wonder where the first place to look would be? Thank you.
It's not the switch. If you think about it, the switch provides power to the dimmer. Nothing changes with the head light switch when you hit the dimmer. Look at the wiring diagram in your FSM and you'll see it's just one wire from the headlight switch to the dimmer.Update: I "borrowed" the working high beam switch from my '65 Barracuda and the same thing happened. In fact, not sure but I believe the low beams might have flickered off this time as well. I know I saw the ammeter go full overboard to the discharge side again. The turn signals, horn, and starter motor seem to work normally.
Then I removed the headlamp switch to find it was the NOS switch I had installed about a year ago. Still looks new on the outside. Time to think it over again.
With the ammeter acting up like that, I am hesitant to do much testing with the battery connected, don't want to burn/melt any wiring.
This is clearly some sort of serious short. You must find it.I have low beam, but when pressing the floor switch for high beam the headlights go out and the ammeter goes to full discharge. I wonder where the first place to look would be? Thank you.
Its highly unlikley that its in the headlight switch since it does not happen on low beam . The only point of concern is that the circuit breaker in the headlight switch should have opened as soon as the current exceeded 15 amps. The first thing I would check is every location where headlight harness goes through or next to metal edges. Headlight buckets for example got me (on my 67). Relays are a great help but do not prevent this sort of problem.Update: With the headlamp switch disconnected and removed from the dash, I started the vehicle and ran it for 15 minutes. The ammeter worked fine (shows more charge at first then less charge), as well as the brake lights, horn, front and rear turn signals, dome light. My multimeter is on the blink, so I need to replace that first to track down any shorts (working alone).
That appears to be roughly accurate although I beleive the author may have been using H6024 lamps. You would have to provide the details. Regardless, what @67Dart273 just posted is worth restating. a) Headlight relays are worthwile for several reasons. b) Its not revelant to the issue you need to diagnose.Reader beware: This comparison I found online may or may not be accurate.
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See post #7. The first thing I did was substitute the floor dimmer switch from my other '65 Plymouth known to be working satisfactorily.Did you scrutinize the floor switch plug ?
See post #7. The first thing I did was substitute the floor dimmer switch from my other '65 Plymouth known to be working satisfactorily.
With the headlights removed, same condition as before: high beam selection shows max ampere discharge on dash gauge.So you have the headlights disconnected. Did removing them remove the short?
So then check the harness from the headlights back to the bulkhead (which I already mentioned). If you do not see anything,With the headlights removed, same condition as before: high beam selection shows max ampere discharge on dash gauge.