inghamjon

Hi, looking for a little bit of help on trouble shooting my fog lights which don't work.

I have a UK 2001 Cherokee which did not come with front fog lights as standard. I looked around the front and I can see that there is wiring available for them. behind the instrument panel there is also wiring available.

I bought a new switch console that inclued the front fog light swtich, and some second hand factory fog lamps. I connected them all up and they don't work. Here is the troubleshooting so far:
1. I checked the bulbs - fine
2. I checked fuse #7 - fine
3. With a test light hooked up to positve terminal of the battery I proved that I have continuity to the switch and to the lights.
4. I took apart the switch and on inspection it has got hot and warped the plastics inside. I have used the plastics, springs etc from another known good switch (my old rear wiper switch) to rebuild this. The 'on' light now works so I beleive the switch to be working now.

So where else to look. The only thing I can now think of is the relay and because the Jeep did not come with stock fogs they did not put the relay in. The relay in the UK model is behind the glove box and not in the PDC as it says in the manual. When I switch on the rear fogs I can hear the relay clicking. When I switch on the front fogs there is no click. According to the wiring diags that I have both the front and rear fogs go through the same relay. What else can I check? Should there be another relay?

thanks
Jon

DaddyCat

With the front switch on do you have power at the front fog light plugs/sockets?

here are some links that may be helpful:

https://www.cherokeeforum.com/f51/ho...-switch-28667/

http://www.jeepforum.com/forum/f11/d...eature-893240/

inghamjon

Thanks Joe, unfortunately the UK spec model must have different electrics as in the links you provided the PDC contains the fog relays but in the UK model the relay is behind the dash. there is also only one which i suspect is because the fogs don't need to be off when the main beam is on here in the UK?

Not sure how I can check that i have power to the fogs with the switch on. I have tested the front connectors with a test light hooked up to the positve battery terminal.

xj wheeler

Good ground? Touch the + & - on the lights to the battery to test them.

inghamjon

OK I have test light lead from the positive battery to the positive side of the connector and that's OK
I have a test light lead from the negative to the other connector and no light so I am guessing here that I have a bad ground.
So I am now going to feed some wire direct from the positive female connector at the light to the positive on the battery and do the same from the negative to the negative at the battery. If the fogs are good then they should light up?

xj wheeler

If you have a bad ground that's probably your problem. If not then yes, you can hook the lights up directly to the battery to eliminate any problems with wiring to test.

Note: this is just for testing the lights not permanent.

DaddyCat

Fog light switch on, test from positive fog light connector (near front bumper) to a bare metal part of the "frame". Scrape a little paint off if needed, you can repaint that spot later. Your test light should light up, if not, you don't have power to the plug.

If the test light lit then with one end of your test light on the same positive side of the connector probe the negative side of the connector. If your test light lit up your fogs should work. If the test light did not light up your negative wires are broken or lost connection.

inghamjon

Thanks for all replies. I have had another go this morning and:
with the fog lights on (plus the headlights 'cos it won't work without them on) I put a test light to the positive connector of the wires coming from the car then touched the frame and nothing. So i guess there is no power to the fogs. This kind of makes sense in that I can't hear a relay clicking anywhere when I turn the switch on which I would have expected. I think the best thing to do would be to rewire the fogs to the switch as I can't seem to follow the wires (they just go into a fat wiring loom that is all taped up). I want to put some driving lights on the bumper as well so I can do both jobs at the same time.

thanks for all your help.

freegdr

turn lights on and connect test light to ground then touch light to fog light plug terminals see if it lights this tests for 12 volts ,switch the test light to posative side of battery and probe again this test for ground...

freegdr

pretty sure non equipped factory fog vechicle will not have relay installed

freegdr

found these two links http://www.jeepforum.com/forum/f11/f...05/index2.html

freegdr

http://www.naxja.org/forum/showthrea...1020497&page=2

DaddyCat

Nice links freegdr, I hope inghamjon reads them. inghamjon you need to use the fog light switch to activate a relay that then powers your fog lights. If you try to power them without a relay you will burn out that little switch.

I borrowed this image from xjguy98, looks correct to me:

inghamjon

I am beginning to wish that I had never started!! The diag above is what I expected to see; switch to relay to battery and lights. All the FSM manuals that I have point to two relays in the PDC that both front and rear fogs connect into. This is not the case on my 2001 UK model. The only relay I can find is behind the glove box. This is working when I use the rear fogs (I can hear it click when I flick the switch) but when I switch on the front fogs there is not click. So I can only assume two things. Either:
1. the wiring for the front fogs doesn't go to that relay (and if they don't I can't see where they do go) and I need to add a relay to the circuit and find the other wires from the fogs and connect it all up
or
2. they do go to the relay but the switch has had it and not working.

From the two links provided it looks like I am not the only one to have trouble. it just seems odd to me that the mounts are there for front fogs, the wiring is there at the fender, the wiring is behind the console for the switch. you would think that this would be plug and play. Sooooo annoying!
I will have a careful read thru the links and have another go.

inghamjon

A small success I think over the weekend. I think that my Cherokee should have two relays but not in the configuration that the fsm says. I beleive that the front and rear fogs are on separate circuits with independant relays and not sharing as the book says. The rear relay is located behind the glove box and not in the PDC which was confusing me. The PDC layout is also different from fsm too with two banks of two relays followed by a bank of four.
Anyway to cut a long story short on furhter inspection of the PDC one of the spaces has the terminals for a relay and I now suspect that this is for the front fogs. The other has no terminals which explains why the rear relay is behind the glove box. I just need to find a suitable relay and keep my fingers crossed that I have found the problem.