brake, tail, & dash lights out

[original owner]

Well My brake tail and dash lights are out as well as the the fan/air controles, the shift lock overide must be pressed to drive it, it is an FJ80 1991, I have replaced all bulbs on the rear of the truck, I have replaced the fuses in the dash and under the hood, I'm checking grounds and wire connections now, with the EWD, (I found an older article where someone else had the same problem but his fix didn't work here)
any ideas on what to check next? any thoughts apriciated

thanks

Brandon
denver
fj80 1991 with 185K miles all stock

 

[concretejungle]

you said you checked all fuses, so that's a little puzzeling. When the brake light fuse goes out, the brake lights, tail lights and dash lights all go out.

 

[semlin]

do you have a trailer harness? check there first. In fact check there even if you don't because there is probably a plug for a harness tucked under the truck behind the ps rear wheelwell as on my brother's 91.

was the 10 amp fuse in the dash for the stoplights blown? Does it keep blowing? Can't see how it would not work if the fuse was not blowing. Maybe check at the fuse terminal to see if you are getting 12volts.

 

[MoJ]

You might try a little bulb grease (autoparts store $1) - apply it to the posts on the fuse and then snap in place. If you can, clean the contacts on the fuse block. Try rubbing alcohol and Q-tip or scrape on it a bit. Don't use acetone to clean it - it'll eat up any nearby plastic bits.

BTW - pretty cool your the original owner. Since you're the original owner I bet you'd be able to give an excellent account of any problems you've had / maintenance you've done over the years. That info would be very interesting to hear.

 

[Beowulf]

Brandon,

Some clarification please. Does it blow fuses and then your replace them or were all the fuse OK but you replaced them just in case?

Follow the above advice from the other replies first. If those suggestions do not fix it then check under the carpet in the cargo area a the very back of the truck. There will be a bare wire (green ?) going from the left side to the right side. Sometimes this wire will get shorted. This wire was port installed with the "factory" tow option.

-B-

 

[cruiserdan]

Green is the correct color for the above mentioned wire.

 

[landtank]

I second the idea of the trailer harness converter. If there is a short it will take out this thing which will continue to short future fuses. Remove it and see if this helps.

 

[Rich]

...
There will be a bare wire (green ?) going from the left side to the right side. Sometimes this wire will get shorted. This wire was port installed with the "factory" tow option.
...

I was horrified [] when I saw that an unprotected wire had been run across the cargo bay underneath the carpet. It is just sitting there, waiting for something heavy to be dropped on it, and having its insulation cut with a short circuit to follow. I reran the wire underneath the truck properly protected inside taped up plastic wire loom.

 

[original owner]

update

OK so here is the story, The lights went out after towing my friends boat out of the lake, a harnes was hooked up when the trailer was wet I think... above simptoms began, after that I removed the trailer wiring because it might be at fault and uhaul might have screwed up wiring the harness

I took off the green wire across the back incorrectly ( oops ) when figuring out how it goes back on it is either the ground across the back or a turn signal wire...(they both come out of a box that flashes the turn sigs and hazards (PS rear) I'm fixing this just need to figure out which one to connect it to.. (there are two green clipped wires one with no power and one that flashes with any turn)

anyway the fuses are fine and never blew, the bulbs are new & I tested the tail light relay and it works,

one thing I found is the fuse for the tail lights is not getting any power at the fuse box teminal, lights on or lights off...the RM says that I should check the light switch but it is working for the headlights/high beams ?

thanks for the ideas

 

[MaddMatt]

You might check the flasher for the turn signals. Years and years ago I used to haul a boat with my dads '87 heep wrangler. If we forgot to unhook the trailer wires before putting it in the water, it would do the same thing, and it was always the flasher that blew. Worth checking anyway.
-Matt

 

[cruiserdan]

How about the tail lamp relay? My bet is the trailer harness may have fried it.

 

[original owner]

still no fix

tail lamp relay tests OK, as do the plug it conects into (ground and hot)

tail fuse #2 has NO power at the fuse block, not blown just no power tested with multimeter

removed the green wire and entire stock trailer wire harness from the back completely,

tested the tail lights with a direct connection from the fuse to the battery and they do light so somewhere between the relay and the fuse, or the light control switch is a problem, or something else is out not on EWD

NO tail lights, brake lights, parking lights, dash lights, licence plate lights, NOR air/blower/fan, glove box light, cig light, ash light but everything else works...

I'm thinking the light control switch or the stop light switch went out, BUT WHICH ONE

thanks for your collective knowledge, I'm beginning to really like this place,

brandon

 

[landtank]

You will need the EWD to effectively troubleshoot this type of problem. I doubt it's wired the same as my 96 or I'd be able to help you.

Best of Luck

 

[original owner]

I have the EWD and some wiring diagrams do not show how one circuit affects the next, eg the brake lights and tail lights are shown on different circuts (though they must logicly connect)

just trying to avoid an electrican and save a few $$$

thanks for the luck I might need it

 

[Beowulf]

The stop light switch should be simple to test. It's mounted above the brake pedal.

-B-

 

[lagwagon]

I would look at the multifunction switch and possibly the ignition switch. It is rare but I have seen multifunction switches get filthy and not get contact and be fixed by taking apart and cleaning. the same with ignition switches. The ignition switch is difficult to take apart and put together due to the little springs and balls. It would also make more sense for it to be the ign switch because of the multiple circuits.

 

[semlin]

OK it is definitely on the taillight relay circuit based on the accessories you list. Acording to the 1991 FSM EWD (#14) there is a fusible link "FL main 2.0L" between the battery and the relay in something called the fusible link box. You can see that all the accessories you list work off that 15 amp fuse from the taillight relay that you have noted is dead. I would therefore check that the white wire to the taillight relay is hot. If it is not I would say fusible link, if it is then the relay leads back to your light control switch. Either way based on what you describe as the origin of the problem I suspect blown, not dirty.

I am also pretty much certain it is not your stop light switch. Power must still be getting there and it must still be functioning or you would not be able to shift out of park. In fact you should still have brake lights as they seem to be ona completely different circuit (EWD #8). Have you double checked this?