I have a 2007 Ford Escape with a passenger side low beam that won't turn on when the headlights are turned on. I have replaced both low beam lights and checked all the fuses. Fuses are ok,none are burned out. My high beams work perfectly as well as my fog lamps. I need any and all advice and information , including any simple wiring diagrams that could be of use . Is it possible that the multi function switch for the turn lights and headlights is the problem?. If so where could i get one and whats the cost?. Thanks

 

Have you checked the socket for power when the switch is in the on position?
I know you say the light isn't working but I would start with the socket first and work backwards.
Also checking for power at the fuse would be a good place.

 

I don't have a wiring diagram so a little limited, if you have 4 headlight fuses (2 for high beam, 2 for low), then swap the low beam fuses over to confirm each is good, some times a visual inspection doesn't show a broken fuse.

If the same fuse for each headlight low and high beam then as far as I can see that points to a broken wire from the point at which they split to each low beam feed to the inop low beam - looks like a single headlight relay and single-pole switching is used on the earlier models, can't confirm on your year without a wiring diagram I'm afraid.

 

No. Power for the headlights does not go through the MFS. In this configuration, the MFS is simply an input to the SJB that tells the SJB what function the driver has selected. The SJB then executes that function internally and it controls all the outputs (loads) such as lighting, signalling, etc.

The headlamps are not individually fused.

The individual circuits are all controlled individually by the SJB. You can check for power at the individual outputs of the SJB for each bulb circuit to see if it's a wiring concern or if the fault is internal to the SJB. The SJB is not readily a DIY repair if it must be replaced as it requires programming.

CAUTION: Do not jump to any conclusions regarding the SJB!!!! Follow the diagnostic procedure!!!!

 

Thanks for your reply and information. One question where is the "SJB" located in my 2007 escape?. Sorry i didn't reply sooner. Mechasus

 

Under the center console, forward.

You can access the fuses through the passenger side foot well, the connectors through the driver's side foot well.

 

I have checked the fuses on my 2007 escape and they are all working with none burned or blown. I also checked the low beams for voltage with the key in and turned on. Using a multimeter, i got a reading of 11.9 volts at the left low beam and a reading of 7.5 on the right low beam. I also tried swapping out both new and old bulbs on the right with low beams turned on, same result no light on the right side. Would it be advisable to run new wiring (positive and negative ) from the left low beam directly to the right low beam?. If not , then what else should i do ? Thanks

 

I would think running a wire like that could overload something. Either the smart junction box or the wiring to the other headlight. The cars of old would have been ok with this, no doubt.
I hate saying this but someone skilled in wiring might be in order so they can track down here the issue is and fix the cause of it.
I don't know what all the SJB runs but if you are able to replace it without issue, at least for testing, this would be the direction I'm leaning.

 

If you slave the two headlights onto one circuit, the SJB will probably flag the attempt to draw double current off one output as a fault and may shut that down also.

Did you check that by back-probing the wire or did you measure that with the bulb's connector disconnected?

 

Thanks for your reply. I checked the voltage with the low beam bulb disconnected from the harness and with low beams powered up. I did that for each low beam light.

 

Okay, you were measuring "open-circuit" voltage which is not going to be enough for this diagnosis. Since the bulb isn't lighting up at all, I'd assume that an in-circuit measurement would be zero at the bulb.

Check the voltage at the output of the SJB with everything connected and the low beams on. That will tell you if the problem is the SJB or the wiring between the SJB and the headlamp connector.

You may want to contact forum advertiser Circuit Board Medics and see if they have any specific history with your particular symptom. If anyone around here would have intimate knowledge of how the SJB works internally, they'd be the most obvious source.

 

wonder if there was ever a fix to this? I am having similar problems with the left (driver side) low beams.

 

The short answer is no. The problems I have are with finding an accurate service manual. Also there appears to be a Smart Junction Box, located at the bottom of the dashboard, which controls, the headlights, low and highbeam, fog lights, and turn signals. The problem is, is the SJB, a computer, an electronic device or a solidstate device and how do I test it to determine whether or not it is the source of the headlight problems. So far, tracing the wiring from fuses 2 and 3 from the battery junction box I haven't found any broken wires and the wiring doesn't match up with any wiring blue prints or showing me any breakout harness. So, until I can get more accurate reliable info, I can't make any further progress, except to maybe find a used SJB from a scrap 2007 Ford escape with a V6.
Thanks for your time and interest Shawn Harris