Trouble with Headlights

[JawsMeetsFord]

Hello, I have a 2003 Ford Windstar without automatic lights. Here's my problem: When the headlight light switch is “on”, the running lights, turn signals, brakes, and the hazard lights all work good, however the headlights do not turn on on either side. When the high beams are turned on only the passenger side high beam comes on. Following the advice of the user manual, the light bulbs were replaced and the fuses tested, they are good. Next the multi-switch on the steering column was tested and is good. Then the wires connecting the bulb plug to the Front Electronic Module was tested with a multi-meter, results are below: When “ON” (low beam) Driver side: White: Hot Red/White: Dead Brown/Yellow: Dead Passenger Side: Yellow/White: Dead Green/White: Dead Green/Brown: Dead When “ON” with High beams Driver Side: White: Hot Red/White: Dead Brown/Yellow: Hot Passenger Side: Yellow/White: Hot Green/White: Dead Green/Brown: Dead Any advice is appreciated, thanks!

[rhandwor]

Have you checked the headlight switch.
Have you checked the dimmer switch?

[JawsMeetsFord]

The dimmer switch, yes and it did what the chilton manual said it should. In the windstar, isn't the headlight switch part of the multi-switch on the steering column?

[rhandwor]

Originally Posted by JawsMeetsFord

The dimmer switch, yes and it did what the chilton manual said it should. In the windstar, isn't the headlight switch part of the multi-switch on the steering column?

http://www.rockauto.com/ search your vehicle then electrical relays switches. http://www.alldatadiy.com/ sells a years subscription about $29.99 It has wiring diagrams needed. Probably than replacing parts. Have you checked all relays for head lights.

[wiswind]

I had a 1996 which had the headlight switch on the dash.
In this case, it was also the circuit breaker for the headlights.
I had issues with my headlights intermittently not coming on right away when I turned them on and also dimming and flickering once in a while.
I my case, I could feel that the headlight switch area was warm when I had the headlights on.
I replaced the headlight switch and all was solved.....
The headlight switch should NOT get warm at all.

In your version, with the headlight switch as part of the multifunction switch, I would be surprised if it is the circuit breaker for the headlights.....but you will need to verify that.

It is also possible for the contacts for the headlights ONLY to be going bad.
I had that happen with the turn signal in just one direction.....all other functions were fine (remember, my '96 multifunction switch did NOT include headlights).
Multifunction switch is not so easy to change.....but can be done.
It takes a bit of patience and being in awkward positions to be able to see what you are doing. I'll bet that is 1 thing that your 2003 and my 1996 have in common.

[tomj76]

I don't know what the function of each wire based on color. The color coding is different than found on my '96. However this is basic electricity, so we should be able to determine the source of the problem with some basic rules.

First, there must not be any short circuits (low resistance connection to the body) and no open circuits (a broken wire or bad contact).

Second, all voltages should be measured relative to the battery negative (or a good electrical connection to the body). Careful when probing to the body to measure voltage. If you're using a DVM you might not make a good electrical contact with the underlying metal through the paint and coatings.

The headlamp has two filaments in it. There are three wires, one that goes to both filaments (the return wire), and two that each connect to a filament. One filament is for low beam, and the other is for high beam.

Both head lamps are usually wired "in parallel", so that the circuit that connects to the low beam filament on one lamp also connects (through another wire) to the low beam on the other filament. The same goes for the high beam and negative return circuits.

When the lights are turned on both lamps should have one and only one wire with +12 v (battery) and the other two wires should be at zero volts. One of those two is connect directly to ground, the other is also at ground, but through the inactive filament.

The wire that is common to both connects to the battery negative terminal. It should never show +12 v on that wire. You should be able to measure low resistance between that wire and the battery negative terminal.

The other two wires should alternately show +12 volts, depending on the high/low beam selection.

If the voltage is present and the battery negative is also connected to the lamp, then it should light.

If you switch between high & low beam and either of positive wires never shows the +12 volts, then there is a break in the circuit somewhere between the battery positive and the light. You've mentioned several places where such a break could occur, such as the fuse or the switch. If you have auto headlights, the switch doesn't carry the bulk of the current, but a electrically control switch must do that.

If you don't have at least one wire showing +12 v, then the light should not be on.

It is possible to have +12 v on two or three of the wires and not get light from the lamp, but only if there is a failure of the return circuit.

Your data shows the following:

________L____H
W:____Hot__Hot
R/WT:_Dead_Dead
BR/Y:_Dead_Hot
Light: OFF OFF

Y/W: Dead Hot
GR/W: Dead Dead
GR/BR: Dead Dead
Light: OFF ON

Notice that you simultaneously have two hot wires in high beam mode on the driver's side. This is suggesting that you have an open circuit in the return circuit, possibly at the contact on the head lamp connector. However, you should also have seen two HOT lines in low beam as well.

On the other hand the passenger side works in high beam, but not low beam, and there is no HOT recorded in low beam. This most likely means that the circuit between the switch (relay) and the light is open. You'll need to look for the break in the line.