headlight wiring question

[Sluggo]

Ok, so when I wired my new harnesses for the head lights I directly copied the car's original headlight harnesses. When I tied them together and tested them the outer(low beam) lights appear to be on high. When I power the high beams the outer (low) dim and the inners come on high.

When I was wiring the low connectors the red wire was clearly in the upper terminal and the green was to the right. Both of the headlight harnesses are constructed this way.

When I looked at the wiring diagram last night after that discovery the green shows in the top terminal and the red in the right. In other words, switched. They are in their correct location in the connector that connects them to the main harness.

Is it even remotely possible that they have been a birth defect and never caught?

Just to be sure, the green should be in the top pin location at the outer (low beam) headlight, corrrect?

 

[Midlife]

My quick check of plugs shows that the red is on top, and the green on the right when facing from the back side. Red is low beams; green is high beam. For 1969, the inner headlights are highbeams only. When the high beams are on, is the highbeam light on on the dash?

You can eliminate the dimmer switch as the switcheroo. It's possible that the wires were switched at the firewall connector, but I have never seen that. Green/black should be at the corner; red/black should be one down and two over next to the purple wire.

 

[Sluggo]

My quick check of plugs shows that the red is on top, and the green on the right when facing from the back side.[nb]Precisely how they were laid out and copied[/nb] Red is low beams; green is high beam. For 1969, the inner headlights are highbeams only.[nb]Don't know the cluster is out and the battery, regulator and solenoid are out as well. Powered the lights up with my power probe[/nb] When the high beams are on, is the highbeam light on on the dash?

You can eliminate the dimmer switch as the switcheroo. It's possible that the wires were switched at the firewall connector, but I have never seen that. Green/black should be at the corner; red/black should be one down and two over next to the purple wire.

Since the rest of the circuit is open, nothing else can be causing the issue. The relays are not yet installed so all I'm dealing with is the headlights. When I power up the low beams they look pretty bright. As soon as I power the high beams up the lows are noticeably dimmer.

 

[Midlife]

Since the rest of the circuit is open, nothing else can be causing the issue. The relays are not yet installed so all I'm dealing with is the headlights. When I power up the low beams they look pretty bright. As soon as I power the high beams up the lows are noticeably dimmer.

That may be normal with two headlights on each side...I dunno. Does the same thing if you unplug the inner headlights?

 

[Sluggo]

That may be normal with two headlights on each side...I dunno. Does the same thing if you unplug the inner headlights?

Good question. I'll check when I go back out.

 

[Sluggo]

This artist's rendering seems to verify that the top terminal in the sealed beam it self is for low beam as do the more professional looking versions.

 

[Sluggo]

Figured it out. I was out doing some testing and noticed that the high beam wire was heating up while I was applying power to it which indicated a resistance fault.

Then, I recalled seeing this post on VMF[nb]http://forums.vintage-mustang.com/vintage-mustang-forum/626245-69-headlight-relay-schematic.html[/nb] while looking for the relay schematic. Clamped a ground and a power wire straight to the battery and the problem was solved.

I guess the power probe does not supply a healthy enough ground.