08 ranger 4x4 Auto 3.0 I have headlights that automatically come on when the parking brake is released. The light switch has no effect in turning this feature off that is until I disconnected the parking brake warning light wire. The parking brake switch grounds a relay or something. Now the light switch works like I would have expected but naturally the parking brake warning light is on ( I could really care less) and the warning alarm mostly stays on untill you get moving a ways down the road but then any time you stop it starts back up again. (I hate those things anyway.)

The truck was originally a Comercial purchase as it was originally sold to Verizon. I dont know if it was some specail commercial feature would like to know that. Some might say live with it but i just like things to be simpler dont want my electrical system working more than needed I like roll up windows too. Besides if i wanted to put better bulbs in there it would just burn them up.
Can anyone help me figure out where I can make a change to the system to prevent the lights from comming on whith the action of the parking brake?
I called the local dealer he said he could not make a chage from the computer. If the parking brake grounds the headlight relay maybe there is something there I may only have to fire out which wire to cut or something? Thanks for your help in advace.

 

Simple answer is no, there is no wire, or wires, to cut to disable DRL(daytime running lights)

Its part of the Circuit board in the smart junction box(SJB, body computer) in the passenger kick panel

DRL uses PWM(pulse width modulation) to reduce voltage at the headlights so they are running at about 60-70% voltage/brightness so won't effect bulb life too much

You could install a switch on the parking brake wire you are using now
Or install a relay on each low beam wire with a switch on the dash to turn them off when you want, without getting the brake light or chime warning

Fuses 3 and 4 in the cab fuse panel are for low beams/DRL, one fuse for each side
You could highjack it there or in the engine bay wiring harness
You must use relays as these are positive voltage wires, the parking brake wire is a ground so a switch only would be fine

More expensive option would be to get an SJB without DRL, I have no way to ID one from the other, maybe Ford Parts Shop can help for that part number

Wiring diagram here

 

That was very helpful thankyou. There are two modules in the upper LH side of the drawing what are they for? Also I am confused by the light switch. Auto and Park dont seem to go through the switch to anyhing. I see auto, Off. park and headlight. I just bought this truck and my old 2005 did not have this feature (was 2.3 liter when I turned the switch all the way to the left it shut the headlights off. I will try it but could it be as simple as I just have one more toggle to the left for auto and all I had to do is turn it one position to the right during the day to turn em off? If so it was only the nut behind the wheel and problem solved i will check thanks again Bob

 

Upper left is the SJB(smart junction box), it is the Body Computer, you are just seeing the parts and wiring involved with Headlights/Fog lights only, there is much more wiring, and SJB involvement, for parking lights, interior lights, ect.........................

You can get your owners manual from here: https://www.ranger-forums.com/genera...1-models-3747/

Maybe it has a way to turn off DRL

In Canada DRL is required on all vehicles sold after 1989, the US doesn't have that, although car makers do add it to most vehicles

 

Just went out and looked at the switch thinking i was just assuming the position all the way to the left should be off but it is the day time run position. The thing is on the diagram the switch shown has 4 positions one off. This switch has 3 positions. Daytime , park and headlight. I wonder if all I need is a 4 position switch?

 

No, I wouldn't think so

Point of DRL is that you can't turn them off, they should come on when key is on, or if automatic in gear maybe, if parking brake pedal is even barely pushed down they will often go off
The head light switch is not part of DRL, but is connected to DRL module, so when you turn on the head lights(or fog lights) the DRL is turned off

 

Dont you think it is intresting that there are 4 positions on the drawing vs my 3? Do all Rangers from this time period have this option? Does everybody with a 2008 or later have the forced day time headlight on requirement?

 

I dont mind having the parking light on it still in its way remides me to fasten the seat belt. Is the beeper integrated with the gage pack like imbedded in the pc board? Can I just dis-arm or disconnect it somehow?

 

Here's the story I was told when trying to get my "Daytime Running Lights" turned off

All rangers from 2006 up,

In the "Smart Junction Box" there is a feature that is used to turn on the DRL's that can be accessed by the dealer or the factory.

This feature can only be programmed to turn the DRL's on, once this feature has been activated it cannot be reversed, this is to stop Canadians from turning DRL's off, Unfortunately it also prevents those of us in the states from turning them off.

There is one way to do it, but it's not cheap.

Buy, from the Ford dealer a brand new "Smart Junction Box", it will need to be completely programmed by the dealer for your truck, during this programming they DO NOT activate the DRL's


Not sure if it's true or not, My DRL's are still on.

 

ignore the 4th position, rangers never had automatic headlights until 2019

and no to your other question, only fleet trucks had it on automatically

 

Well that might make sence. I will look deeper into this when I called the dealer the guy after several non returned calls claimed that it could not be reset. I will diligently respond with what I find. Now i wonder how difficult it would be to R&R the box and if I could get a box from a yard and have that programed?
How difficult would it be to pull the box and plug a new one in if I could get the dealer to reprogram or program one?

I dont know if they did this with all the trucks or if like you suggest it was for Canadian, california or a commercial opton. I woudl not doubt since my truck was a commercial order that that was how the box was burnt in. Does everybody wiht at least a 2008 truck have "day time running head lights"? If anyone else reads this collum and has at least an 08 or later please respond.

 

As said DRL is not connected to main light switch, the SJB monitors main light switch power thats all, DRL is a separate module


If you want to disable DRL you can use 2 relays, one for each head light wire, these would be open so no head light power
Power the relay ON using the Brown/white wire on the main light switch, so when you turn on the head light switch relays would be powered on and close, and head lights would come on
So automatic operation no extra switch

 

way more time and money than its worth. don't go making your truck an electrical frankenstein

 

I would have to look at the drawing but am guessing I could just build a harness to plug into the exising head light sockets w relay. The head light bulbs would just pluc into the harnessthe harness into the headlight wireing This way nothing is chopped up just an extra harness encorporating the relay. Would be simpler if I could just break the ground at the headlights--maybe. All I woud have to do is add one wire to power up the coil on the realay and that could be spliced with one of those through the insulation splices I am thinking. This way have not really made a frankenstine truck out of it just disconnect the harness and it goes back to stock.

My 05 did not have this feature. I think the battery is meager anyway. I needed the car otherwise I would have tried harder to put a larger one in. Will try to talk to a dealer about the controller and see if he/ford can program a new one and I install it? See where that goes.

 

If you disable headlight grounds then Flash-to-pass would be off as well, just FYI

 

If someone else was reading this and flash to pass was important to them I'm glad that you mentioned that. I really dont use it anyway myself. Where I grew up people dont use that feature. It is considered to be rude. As a result I really dont like it and when people use it behind me it makes me very annoyed.

These systems are different than the old a wire does this electircal system with a lot of nuances. I'm learning here with this excercise which is good as it will help me maintain my rig going forward.

 

Any where I have lived when you see someone traveling in the opposite direction, flashing headlights it means "warning, police ahead, or other danger", lol