Parking /running light need help

[DEEPWOODS]

Park/ running lights work till I pull headlights on then both front parking lights go out rear stay on and work fine . So I replaced headlight switch still don't work . I checked for power at the plug and pins in the buckets and no power when headlights are on . I don't know what to check next

 

[bronco loco]

Need to make sure you front parking lights circuitry is very well grounded.

 

[Scoop]

What year is your Bronco?

I'm guessing you have an early year Bronco, 68 or earlier?? If so, that is how they are supposed to work. Parking lights did not stay on with the headlights on prior to 68.

Edit: Actually I just checked my 69 and the parking lights go out on it as well. I'm not sure exactly when this was required for light trucks, but all passenger cars changed in 68 by law.

 

[DirtDonk]

Yeah, our lowly utility trucks got away with stuff for at least a year or two on most things like that. Maybe they officially changed when the turn signals went to the larger ones?
Does your '69 have the old smaller turn signals Scoop? Or the later style?
And did it happen to have side marker lights too by any chance? Or still sporting the reflectors? Been checking into this since I'd seen some few '69's with side markers, but no way to guarantee they were not owner installed.
Thanks

For those that have the older wiring setup, I'm pretty sure it's just a matter of unplugging the connector from the switch, detaching one wire and relocating it to the proper blank location to have the lights stay on. The switch is capable of doing it either way. Just the wire location for the running lights changed.

Paul

 

[B RON CO]

Hi, X2, my 66 Bronco and 66 Mustang work the same way. Good luck

 

[Scoop]

@DirtDonk, 69 was a transition year for a few things and my 69 is a later build. It has electric wipers, the newer top bolt pattern and it does have the larger parking light lenses. And yes, light trucks were delayed a year or 2 on things like safety and emissions requirements as the federal government phased things in. But then California marched to it's own drummer for this kind of stuff!!

Does anyone know for sure what year the Bronco did change over the parking lights to stay on with the headlights?

 

[Broncobowsher]

That's how Ford wired the parking lights up until the laws changed in ~'70.

It's a leftover from the days of generators. Generators didn't charge very well and to help preserve what little output they made they did stuff like this. The thought was they could save a couple of amps by turning off the front park lights (that are redundant since the headlights are right next to them and way brighter).

 

[surfer-b]

If you want them to stay on, remove the plug that hooks to the headlight switch, remove the blk/yel wire(front parking lights), and splice it to the brown wire(rear parking/running lights). I removed the pin and added the blk/yel wire with the brn then reinstalled it, but you can just splice it if you want.

 

[DEEPWOODS]

It is a 70 I was told when I bought it. It has no side marker lights . My 73 and 75 stay on with headlights so I thought this one was supposed to. I only have a hand written bill of sale no title so no telling what year it is. I will leave it like is is wired thanks for your help Thanks again ,Keith

 

[75302auto]

Law changed in 1968. My Bronc is a 75', but my 1968 Ford F100 Ranger was the first year that the marker lights were installed on Fords and also were meant to stay on by law while the headlights were on. They did not go off when the headlights came on. You probably just have a grounding issue. Check for that first.

 

[DirtDonk]

It is a 70 I was told when I bought it. It has no side marker lights. I only have a hand written bill of sale no title so no telling what year it is.

Have you ever put the VIN into one of the calculators, or asked the folks here that know that stuff? Be interesting to find out what year model yours is exactly. Even interesting to find out what month it was built if that is known.

Paul

 

[DEEPWOODS]

The vin is U15GLK49823 I don't know how to enter vin calculator

 

[DirtDonk]

The Broncohio website indicates it's a '71 model year built in November of '70. (http://www.broncohio.com/tech/ebvins.html)
Mine was built in December.

Sounds like yours could be a bit of a Franken-Bronco, but that serial number should be on a '71 model year truck.

Paul