No foglights, marker lights, taillights or cluster lights....

[DennyStew]

Hello all...I am new to the forum and desperately need help. I have the problem as described above in the subject line with my 2001 Explorer Sport. I have all the typical symptoms...no lights as described above, but my headlights, brake lights, turn signals and interior dome lights all work fine. I have replaced both the headlight switch and dimmer switch. I have electrically checked every fuse in the block and every relay in the distribution box under the hood. When I disconnect the battery and then reconnect, the marker lights upfront, the tailights and the cluster lights all blink twice together but that is the only time they work. I am completely frustrated and stumped. Can anyone help please?

 

[J_C]

Seems likely to be the Park Lamp Relay, try swapping it with the one-touch down relay. It's in a box on the right side of the driver's footwell.

If that doesn't turn out to be the problem, grab the 2nd Gen Wiring Diagrams linked in my sig and check the file named exterior-lights-exterior-lamps.

The fog lights out may be a separate issue. There is a fuse for them (#8 in the under hood distribution box) but since you state you checked them all, it's probably a separate relay for them under the air intake filter box.

I don't know if there are any differences between US and Canadian Explorer lighting circuits, but suspect the relays either way. In some regions and vehicles, their fog lights won't come on if the headlight high beams are on... illegal or something.

 

[DennyStew]

Seems likely to be the Park Lamp Relay, try swapping it with the one-touch down relay. It's in a box on the right side of the driver's footwell.

If that doesn't turn out to be the problem, grab the 2nd Gen Wiring Diagrams linked in my sig and check the file named exterior-lights-exterior-lamps.

The fog lights out may be a separate issue. There is a fuse for them (#8 in the under hood distribution box) but since you state you checked them all, it's probably a separate relay for them under the air intake filter box.

I don't know if there are any differences between US and Canadian Explorer lighting circuits, but suspect the relays either way. In some regions and vehicles, their fog lights won't come on if the headlight high beams are on... illegal or something.

View attachment 156486

Thank you very much for your response. I will have a go at it tomorrow and let you know. I appreciate your time.
Dennis

 

[DennyStew]

Thank you very much for your response. I will have a go at it tomorrow and let you know. I appreciate your time.
Dennis

So I found the box you referred to. The relay config is not exactly as the one you posted, but similar. I meter-tested each small relay and even rotated them in the box. Still no lights...I am nearly out of my mind with this problem.

 

[J_C]

I don't know when/what changed relay box layout but here's another one. Meter testing would require putting 12V across the coil to energize it and close the open relay contacts, but assuming that one you swapped into the park lamp position was working in its prior position then it should have kept working.

Beyond that you're left using a multimeter to trace all along the circuit to see where 12V stops. I've edited the 2nd pic to leave only the parts of the circuit under consideration, the rest just branches out to the other lights at point "S401" on the diagram, or "S244" for the tail lights. The problem would be at S401 or before it to affect everything. I'd start by turning the headlights on and measuring whether there is 12V on relay socket pin 5, and 1, and 12V on headlamp switch pin 3 when it's turned to parking lamp on position.

 

[DennyStew]

I don't know when/what changed relay box layout but here's another one. Meter testing would require putting 12V across the coil to energize it and close the open relay contacts, but assuming that one you swapped into the park lamp position was working in its prior position then it should have kept working.

Beyond that you're left using a multimeter to trace all along the circuit to see where 12V stops. I've edited the 2nd pic to leave only the parts of the circuit under consideration, the rest just branches out to the other lights at point "S401" on the diagram, or "S244" for the tail lights. The problem would be at S401 or before it to affect everything. I'd start by turning the headlights on and measuring whether there is 12V on relay socket pin 5, and 1, and 12V on headlamp switch pin 3 when it's turned to parking lamp on position.

View attachment 156506

View attachment 156507

Here is the box in my driver's footwell with the config I'm talking about.

I electrically tested the four F57B relays as you have described (energizing the coil; testing for resistance). I then rotated them just to cover all possibilities. I also replaced the larger square relay (black one; FOAB..?) above with a new unit. No success...I will proceed as you have advised with the trace. Thank you very much again for your time. Please stay tuned...

 

[DennyStew]

I suppose I will have to remove the box to see which socket has the tan/white wire(s) leading to it. There's no way to definitively know by just looking at the front.

 

[J_C]

Remove fuse 11 and use a multimeter to check for continuity between fuse 11 out and each socket location's pin 1 or 5, since the tan/white connects the two.

Keep in mind that if your footwell relay box changed, it might be possible that something else is different too. I mean if your owners manual indicates some other fuse than #11 is for this circuit then trust it more than me.

 

[J_C]

Wait. I got curious and looked up a 2001 Sport relay box that matches what you pictured and don't see the exterior lights relay in it!

I don't know where it is in your vehicle unless it's the "Indicator Flasher Relay", but isn't that one of those mechanical flasher modules for the turn signals?

2001 Explorer Sport Relay Box

 

[DennyStew]

Relay module #1 above looks a lot like the picture I posted in my previous post...If that's it, then the park lamp relay is not there.

Relay module #4 below shows the park lamp relay housed within. This module seems to be somewhere in the instrument panel. That's where I'm off to next...

 

[J_C]

That relay seems to be in the driver's side rear quarter panel, at least that's what member handyman2011 stated here for his '98 Sport:
Parking Light Problem

I'd just going to backtrack and state that I have no idea where it is, lol.

 

[DennyStew]

The one in the rear is located inside the tire jack compartment. The one I'm referring to seems to be located behind the instrument cluster.

 

[DennyStew]

The one in the rear is located inside the tire jack compartment. The one I'm referring to seems to be located behind the instrument cluster.

Going out to look for it now...

 

[DennyStew]

Going out to look for it now...

There is no relay module inside my jack compartment. There is basically nothing in there at all. I cannot see another module behind the instrument cluster either. I haven't pulled it all the way out, but have shined a light back there and can't really see anything.

 

[DennyStew]

There has to be someone on this earth who has changed a park lamp relay in a 2001 Explorer Sport...(sigh).

 

[J_C]

A few other thoughts I have are to pull the headlight switch to see if it's not conducting through the Parking Lamp output in the on position, and if you have the Autolamp feature (mirror with adjustable time-out and light sensing to turn headlights on) there may be corrosion of the wires going to it.

Another idea is that if your '01 is built after a certain date (7/24/00 ?) it may have the next generation PATS security system and maybe more is also changed over to the next generation wiring meaning this circuit may be more similar to that of a 3rd gen Explorer.

If that is true, it could be more like the following wiring diagram with the Park Lamp relay in the "Vehicle Security Module", wherever that might be - Except in our prior generation that was in the left rear quarter panel (for Sports too or did they even have that factory option ??):
2004 NBX Exterior Lighting Woes!!!!

As far as your prior picture of the dash module, I suspect that what they did there was just draw it sideways and out of proportions (their diagrams are horrific, lol). Notice how the following two pictures could be about the same thing, yet you've already pictured a box in yours for that location that looks like neither:

Instrument Relay Module 4

vs this rotated 90 degrees

 

[J_C]

One other possibility I might entertain, considering the age of the vehicle and having a desire to work towards a known outcome if other avenues become exhausted, is DIY wire this.

IF your circuit is like the diagram I posted in post #5, then the Headlamp Switch is not just a logic switch to trigger the relay, it's directly switching the Parking Lamp current from pin 5 to pin 3. Since you can't find the relay, or I haven't even considered the possibility yet that you Just Don't Have One which seems a lot more likely if you don't have the Autolamp headlight feature, you could wire the Headlight Switch output pin 3 to the closest wire you can find that is the common positive for all these lights. That wire is brown in the diagram in post #5 but if other things are different then maybe the wire color is too - It is probably the same color at the Parking Light bulb(s) connector(s).

In the diagram that's a brown wire going to junction S401. If I were going down this route of DIY wiring, what I might do next is grab a spare long piece of wire, connect it to battery positive then pull out one of the Parking Light sockets to access its positive wire lead, being careful to be sure you don't pick the ground lead as this would make a direct short to ground from the battery.

Having selected the bulb positive lead you could connect the jumper wire temporarily to see if all lights work. I think I'd prefer to have a fuse on that temporary jumper wire but then again if there were a short in the circuit, it seems like it should have blown out the fuse box fuse for it already.

Anyway if that jumper wire will get the lights working then you'd disconnect it from the battery positive, connect to the Headlamp Switch instead and string it to one of those Parking lights positive leads permanently. This assumes you have already tested that the Headlamp switch works, does produce 12V out on pin 3 when turned on. This assumes your Headlamp Switch stayed the same too, lol.

 

[J_C]

There is no relay module inside my jack compartment. There is basically nothing in there at all. I cannot see another module behind the instrument cluster either. I haven't pulled it all the way out, but have shined a light back there and can't really see anything.

I saw a post where someone with an '02 Explorer has some sort of box at the rear of the RIGHT rear quarter panel. Picture and topic as follows, the problem is different but it indicates to me that something was placed in the right rear qtr panel with the design change:

Explorer XLT: I have a 2002 Explorer. Door ajar light stays…

 

[DennyStew]

So all of your thoughts are good ones, and I appreciate your time more than I can say. I will most likely begin the chase as you've suggested here very soon. One thing still bothers me though...I have been comparing all the relay module diagrams and pictures that we have posted here. I believe right now that there is at least one more relay module in the truck somewhere that I haven't found yet. I guarantee that there is nothing in the rear quarters on either side. I'm going to continue the search up front and keep digging on the 'net. If I can't find that damn relay module, then I will indeed have to consider the DIY job.

 

[DennyStew]

Ok...so I am pretty happy to report that I have finally solved this maddening mystery and restored my tail lights, dash lights, tag lights and parking lights. The actual solution was not what I was expecting, and it took a lot of research. As you know, I have been searching for the elusive park lamp relay on my 2001 Sport 2-door. I managed to locate 2 other relay modules in addition to the main distribution box. The little one under the air filter had only one relay in it and it was a larger square one, not the little rectangle one that the park lamp relay should be. I found another one up on the right of the driver's foot well as suggested. I was hoping that it would be one of the following configurations...

or this...

But the one in my truck was neither one of these. Mine looks like this...

Which of course, is actually this...

So I decided that I was still missing at least one more module relay. Short of tearing my entire truck apart however, I just couldn't find another one. Immensely frustrated, I decided to make sure that I was at least working off of the correct I/P fuse panel diagram. I compared the one I was using to the actual I/P fuse block I have. I found a few discrepancies, so I went looking for others to compare. I finally found one for an actual 2001 Sport, not a Sport Trac or anything else similar from the same generation. The original one I had indicated that fuse #5 (15 amp) was "not used". That space in my fuse block was indeed, empty. The later diagram that I found indicated that fuse #5 was for the "Park Lamps". So I put a new 15 amp fuse in there, and guess what? Yeah, all the lights worked.

You're probably thinking that this guy is an idiot. Well maybe, but I would swear in a court of law that I was sitting in the truck with the engine running when the lights failed. I know I was, because I went out there at night to aim the headlights. So if it was just a failed fuse, where did it go? Why was the space in the block empty? I'm still lost on that one...

I did pull all the Maxi fuses to test them and then reinstalled them. Maybe that shook something up, I don't know. Believe me, I'm just thrilled the problem is solved, but in the end I'm not 100% sure what the fix actually was. One more thing, I never did find the damn park lamp relay. It's not in the main box, not under the air filter, not in the footwell and not in the rear body panels on either side. If someone else reads this some day and you know where it actually is on my 2001 Explorer Sport, I would love to hear from you.