Hi all

My headlights will not work at all.

My high beams will work if hold the switch in the back position, but not when it is in the forward/lock pos. I have tested the plug at the lights and there is no power there unless it is in highbeam flash to pass pos.

I have power at the on/off panel, but no power on the orange, yellow, or black wires.

All the fuses are operating.

ANy ideas before i go and pay for a diagnostics check?

Thanks all!

 

I can give you some info from my 2000 wiring diagram (yours may be different). It appears that the flash-to-pass circuit does not use the headlight relay. Check all fuses (in both battery box under hood and panel under dash), then test the headlight relay.

..........................Scott

 

Thanks for the reply Scott.

I have chacked all fuses and they all seem fine,I even replaced them to ensure this.

Where can I find this relay?

Thank you

 

The manual states there may be a problem with the:
-Fuse Panel
-Circuitry (wires)
-Multi-funtion Switch

If you have hi beams but not low beams and the fuses are receiving 10+Volts, the problem is with the circuitry. Check the DG/O & DB/W wires. You'll need to check the wires from the switch all the way to the headlights.

It sounds like either the wires or the Multi-Function Switch.

Here's the wiring diagram for my '97.

 

Thanks Aj

I do not have a manual, so i was lost as I could not find any online.

I will go check these wires now.

Also I was told that the r/y wire may be the culprite as well. This is the one from the headlight switch to the multifunction switch, but I have power on the wire at the headlight switch.

Could you tell me why the multifunction switch would cause this.

Man i wish i would have been born with these skills.

 

On mine, the relay is in the main fuse/junction box under the hood.

Do you have low beams? If so, you have power to the multifunction switch which would mean the relay is OK, and as AJ suggests, it could be the switch.

No one is born with it! Give it a try and you'll learn a lot about your truck. Trace the voltage from th main fuse to the lights using the wiring diagram. You can get a cheap volt meter or just a simple testlight.

................Scott

 

I have no low beams at all and all fuses are operating.

The test light indicates no power at the headlights.

High beams only work when i hold the flash to pass back.

 

The red with yellow tracer wire enters this switch and exits this switch through contact positions (low beam) in the multi-function switch. Since you have flash to pass then the other circuit is probably okay. There is a 7-pin " Gray" connector located right above the central fuse box and to the left of the steering column. This connector is the distribution for the Multi-function switch and headlamp circuits.
Looking at this connector, it has 3 pins on one side (we will call it left side) and 4 pins on the (right side).

3 pin side:
pink with yellow tracer wire = mode selection input
dark blue wire = signal return
light blue orange = interval delay

4 pin side:
red with yellow tracer wire = power in to switch ( hot in headlamp) !!!!!! " see note below"
red with yellow tracer wire = dimmer to low beam circuit **** "see note below"
gray with orange tracer wire = dimmer to high beam circuit XXXX "see note below"
dark blue with orange tracer wire = flash to pass

Note:
If you view this connector vertically and look at the wire colors above then you can orientate this connector to do the testing.

!!!!!! = power feed on this wire to multifunction switch main light switch has to be full on in the headlamp position to do the following tests.

**** = you can test the ouput/mode (low beam) of the multi-function switch here, it is a positive voltage with respect to ground.

XXXX = the output of multi-function switch in high beam mode again positive signal.

If you have power flow (red/yellow) to this switch and not out then it is either the connectors (inside steering column) to multi-function switch or the switch itself.
If you have power out in the output modes, then recheck fuses/wiring harness.
Hope this helps out.

 

 

AB:
What year is that diagram for. The one I referenced to is a 1999/2000. The Red/yellow that leaving the multifunction switch in low beam mode (my reference) and the print above shows a red/black (your reference).

 

Ok I think I located the connector....but this one is black and has about 14 wires connected to it (in and out). The pins look like this

o - o o
o o o o
o o o o
o o o -

or similar...this is on both sides of the connector of course

The only gray connectors I found were mounted on the firewall way in the left hand corner and there were two gray connectors. Both had more than 7 wires.

When I disconnected the black connector, I no longer was able to use the flash to pass, so I am assuming I have the right connector and now need to just test the colored wires you stated and leave the others alone. Correct?

Thanks for all of the help from you guys, the truck is going in tomorrow to Ford to get a diagnostics check done, but I want to find the culprit so they dont charge me an arm and a leg. Also I would love to know what I am talking about.

 

wfstewart,

The only wire not showing power is the small dark blue wire (signaL return)<<<is that for turn signal?

Imput and Ouput red/yellow wire has power and at switch

lightblue has power

pink w/ yellow was for the wipers

gray/orange works when i hold flash to pass

dark blue w/ orange works (not sure what this wire supplies)


When these wires go into the switch, where do the wires come out at? Do the exit the same terminal under diff colors?


Now I really have no idea where the problem lies

All fuses are good

Anymore ideas?

Thanks again

 

Ok, the red/black wire the diagram is referring to, does not have power on the imput/output side.

The thing that boggles me is that red/yellow wire. Which one is actually the right one?

There are two red/black wires exiting the firewall and neither of them are powered

 

Sorry for all the post


I just found something interesting. I pushed my multifunction switch to forward to the lock position and when I almost got the full forward pos. the brights came on and only stayed on in a certain area and i had to hold it there.

I could then use the headlight switch to turn it on and off. (HIGH BEAMS ONLY) still no low beams.

Does this mean that my multifunction switch is definately the culprit?

 

Well the multi-function switch or the connectors right at the switch are faulty but the low beam circuit is still questionable. What I don't know is what color the wire for the low beam circuit is suppose to be. The above shows a red/black and the connector I listed is suppose to be to the right and above the main light switch. It may very well be that the harness and connectors are different from 98 to 99+ F150's.