both low beam and high beam headlights are out.

[landcruiser3DP]

legends,
i walked out tonight to my headlights not working. i'm not driving at night so i'm not entirely sure when this started. normal headlights and high beams on both sides don't work and i'm not sure what's going on.
about six months ago i added a slee harness because i was doing some night driving and wanted more lighting.
in the last week i bought a car refrigerator at goodwill and i tested it out once or twice while driving. it plugs into the AUX outlet and is only on when key is in the ignition and on. it seems to test out fine so i'm keeping it.
i admit to having one weird headlights not turning off issue which i solved by getting rid of LED interior lights and going back to incandescent. i also still have a weird issue where the headlights,sidelights are brake lights have been going on when the hatch is opened (and the headlights are on at the stalk) even when doors are closed.
also my upper rear brake light isn't working.
anyway was hoping for some tips here as i try to troubleshoot.
i'm going to (1) pull out the electrical manual (2) check for any fuses or relays under the hood (3) check for 12V at the headlights (4) start pulling apart the harness to the upper rear brake light.
am i missing anything?
THANKS

 

[robertaleon]

Similar issue - started last week. I checked the high and low lamp fuses under the hood - tested good, no change. Purchased an aftermarket relay to rule that out - tested good, no change. Some posts have mentioned that blown low beams can prohibit low and high beams from working. I plan to try new bulbs. Other posts mentioned testing to see whether the flash/pass feature makes the high beams come on; may be worth testing on yours. The flash/pass just illuminates the dash light, my high beams do not come on. I have the older Slee harness with Hella 4K lights and the aux lights don't work either. Replaced that fuse and no change. I plan to check grounds and the two Slee relays this weekend to rule that out.

Good luck!

 

[jonheld]

Below is the OEM configuration. I don't use Christo's headlight harness. Never found the need with the 9011s.

Single relay supplies +12 to all 4 bulbs.
Fuses are for left side/right side, not high beam/low beam.
Separate ground paths for high beam/low beam.
Bad or open bulbs in a any position will have no effect on other bulbs, unless you change the laws of physics.
If all 4 are out, then most likely no +12 to bulbs.

 

[landcruiser3DP]

Similar issue - started last week. I checked the high and low lamp fuses under the hood - tested good, no change. Purchased an aftermarket relay to rule that out - tested good, no change. Some posts have mentioned that blown low beams can prohibit low and high beams from working. I plan to try new bulbs. Other posts mentioned testing to see whether the flash/pass feature makes the high beams come on; may be worth testing on yours. The flash/pass just illuminates the dash light, my high beams do not come on. I have the older Slee harness with Hella 4K lights and the aux lights don't work either. Replaced that fuse and no change. I plan to check grounds and the two Slee relays this weekend to rule that out.

Good luck!

thanks so much. keep me updated and i will do same. it's odd it is both bulbs isn't it...?

 

[landcruiser3DP]

Below is the OEM configuration. I don't use Christo's headlight harness. Never found the need with the 9011s.

Single relay supplies +12 to all 4 bulbs.
Fuses are for left side/right side, not high beam/low beam.
Separate ground paths for high beam/low beam.
Bad or open bulbs in a any position will have no effect on other bulbs, unless you change the laws of physics.
If all 4 are out, then most likely no +12 to bulbs.

View attachment 4156556

hey. that's awesome. i'll study the diagram with your explanation and keep learning here (which is great).
i don't quite follow - well the point about not high and low but left and right side is saying there is a fuse for left and one for right?
also all of this is indicating - well i test for power to the fuse box under the hood for the relay to verify it is getting 12V? then if i see power there i replace the relay since relays can be bad in weird ways?
and i check the grounds for the headlights?

 

[jonheld]

hey. that's awesome. i'll study the diagram with your explanation and keep learning here (which is great).
i don't quite follow - well the point about not high and low but left and right side is saying there is a fuse for left and one for right?
also all of this is indicating - well i test for power to the fuse box under the hood for the relay to verify it is getting 12V? then if i see power there i replace the relay since relays can be bad in weird ways?
and i check the grounds for the headlights?

Again, I don't have Christo's headlight harness. If it came with a schematic, then reference that.
Again, this is the OEM configuration.

What does it say next to the fuses?

Now follow the schematic:

 

[jonheld]

Looking at Christo's website, what he's doing is using the OEM headlight harness as a logic trigger for the 2 relays that draw power directly from the battery positive.
So a failure on all 4 bulbs using his harness could be on the passenger side connections to the OEM harness (unlikely), or passenger side fuse (check fuses with a meter, not eyeballs), or the single ground point on the passenger side inner fender that he's using as ground for the relays (more likely).

IMO, and this is just MY opinion, the concept is a good one, but it introduces more potential points of failure. I like to keep electric as simple as possible.
What I have used is his high beam jumper harness to build my aux lamp circuit, but that's nothing more than a pigtail with connectors.

https://forum.ih8mud.com/resources/aux-lamps-using-a-rear-heater-switch.93/

 

[jht3]

have you tried swapping the aux harness relays? high to low?

get out your voltmeter and check the factory low beam plug on the drivers side. that's the one the slee harness uses as its trigger.

 

[landcruiser3DP]

hi all.
looking to troubleshoot this properly this weekend so very much appreciate the help. please let me know if i am tracking here:
1. i quickly checked the slee harness ground and it seems secure. it also seems firmly connected at the battery. have not checked further towards the headlights as this takes some digging.
2. i tried flashing the high beams at the shell but did not get anything.
3. i pulled both 15A fuses (visually these look good) and replaced with new ones. i had the headlights on at the stalk at the time and i think i heard an audible click of some kind upon inserting the second fuse (from the top of i recall correctly).
4. no light so i replaced the relay with a new one and still no light.

next steps i am trying to piece together.
A. are there relays in the slew harness i am being told to swap left to right? or shouid i also consider replacing these relays?
B. am i checking for power at the fuse box for both fuses and for the relay?
C. am i checking for power where the slee harness plugs into the main harness?
D. what/where ("L1") is this light retainer relay?

also what am i missing please?

THANKS

 

[jonheld]

hi all.
looking to troubleshoot this properly this weekend so very much appreciate the help. please let me know if i am tracking here:
1. i quickly checked the slee harness ground and it seems secure. it also seems firmly connected at the battery. have not checked further towards the headlights as this takes some digging.
2. i tried flashing the high beams at the shell but did not get anything.
3. i pulled both 15A fuses (visually these look good) and replaced with new ones. i had the headlights on at the stalk at the time and i think i heard an audible click of some kind upon inserting the second fuse (from the top of i recall correctly).
4. no light so i replaced the relay with a new one and still no light.

next steps i am trying to piece together.
A. are there relays in the slew harness i am being told to swap left to right? or shouid i also consider replacing these relays?
B. am i checking for power at the fuse box for both fuses and for the relay?
C. am i checking for power where the slee harness plugs into the main harness?
D. what/where ("L1") is this light retainer relay?

also what am i missing please?

THANKS

IMO, it would make more sense to unplug Christo's harness and plug the bulbs back into the OEM harness and see if you have lights.
That eliminates 50% of the potential problems.
If you have lights, then you know that the issue is with the Slee harness. If you don't then the issue is with the OEM circutry.

 

[jht3]

you have no low or high beams?
you sure all your bulbs are good?

go to the passenger side and test the factory plugs there. there is no battery in the way, and the coolant overflow pops out easily.
find the factory headlight plugs and put bulbs in them (or unplug the slee harness plugs and use the installed bulbs)
do you have any lights?
if no, you have something going on OTHER than the aux harness

get out your voltmeter
put the black on the battery neg, put the red one in each of the open connectors for the headlight relay. two should have battery voltage (1, 3), two should show nothing (2, 4)
unless you've blown your fusible link, this test should pass

if it does pass, put the relay back in
turn on the ignition, turn on the low and high beams
insert both voltmeter probes into the pins where one of the 15 amp relays goes. now do the other. you should see battery voltage
unless you've blown all your bulbs, this test should pass

 

[Shoredreamer]

I had this issue years ago and it turned out to be some sort of wire failure near the diode, or the diode itself. I ended up bypassing the diode and running my own wiring between the head light relay and light retaining relay. I had the Slee harness at the time too which I ended up deleting.

Do as John @jonheld says and eliminate the Slee harness from the issue first by plugging bulbs directly into the OEM bulb sockets. You’ve already got the wiring diagrams, so if no lights after testing the Slee harness I would get a voltmeter, some jumpers to test with 12v and blue tape and mark the headlight circuit stream from battery to bulb sockets. I like to start at the battery and go towards the component testing for 12v until you find your issue.

 

[landcruiser3DP]

gents! thanks a ton for this. this kind of help on this kind of issue i find super helpful. somehow it makes it more obvious what you need to tackle.
an update please but also a follow up in case anyone is interested in helping me with some further electrical study?
right now i see both high beams working but only the right low beam works. the left low beam is out as you can see in the photos.
how i got here:
i replaced two fuses and then i replaced the relay. next step was i finally found time to remove the slee harness. i left it in place the harness.
1. i'm guessing one or both of the relays in the slee harness (sorry no pic yet) are broken? or is there a good way to test this? apply 12 V DC power to each and see if i hear a click?
2. i could have tried to see if i was getting power to the relay outlets on the battery side? is there a good way to test if the power is getting to the headlight side? i guess turn on the low or high beams and apply a volt meter to the contacts for the relay on the headlight side?
ALSO. can anyone help me "read" this diagram a little better? it seems like a good diagram to learn on since it's so intuitive to use these?
like:
if the head relay goes out all the headlights and the high beam light in the dash is out?
if one bulb goes out obviously only the one bulb is bad? or it's wiring that goes to the socket that is bad?
how do i "read" these two head fuses? if the left hand one is out - er - does that mean only the low and high beam on left side are out? is it the same on the right side if rhe right side fuse is out? i don't understand how to red some of this stuff like the Red Yellow wires connecting into the connectors (?) on the left and then there are White Black wires that seem to go from the right side wiring to the connectors on the left side? or can someone help me understand how these - well also the grounds work on this diagram?(!)
finally on the combination switch - can anyone explain how i should be reading how it works electrically...?

 

[TreadingLight]

Your next step should be to test the connector going to the bulb that doesn't light up.

* Disconnect the wire from the back of the bulb.
* Photograph connector. Take note of the wire colors going to that connector.
* Turn on low beam headlights with ignition off.
* using a voltmeter or test light, probe the low beam (negative) and common (positive) terminals. You should see ~12v across w-b (ground) and r-l (common positive). Try all the combinations to be sure.
* repeat with high beams on, probably across r-y and r-l.

Report back.

 

[jonheld]

if the head relay goes out all the headlights and the high beam light in the dash is out?
if one bulb goes out obviously only the one bulb is bad? or it's wiring that goes to the socket that is bad?
how do i "read" these two head fuses? if the left hand one is out - er - does that mean only the low and high beam on left side are out? is it the same on the right side if rhe right side fuse is out?

That was explained to you in post #3. Please re-read it.

i don't understand how to red some of this stuff like the Red Yellow wires connecting into the connectors (?) on the left and then there are White Black wires that seem to go from the right side wiring to the connectors on the left side? or can someone help me understand how these - well also the grounds work on this diagram?(!)
finally on the combination switch - can anyone explain how i should be reading how it works electrically...?

It's a lightbulb. All you need is +12 and ground.

Low beams have a hard ground connection on pin 1 (W-B) that runs to ground points EA and EB (left and right inner fenders).
When the combination switch is turned to the HEAD position, pin 13 of the switch is connected to pin 11. This energizes the headlight relay and sends +12 to the 2 fuses and to pin 2 of all 4 bulbs.
Since the low beams have a hard ground point on pin 1, the low beam bulbs light.

The high beams are a switched ground through the combination switch.
When either the HIGH or FLASH position is selected, pin 12 (hi beam ground path) of the combination switch is connected to pin 9 (ground) and the hi beams light.
You'll notice in the FLASH position on the combination switch pin 12 is connected to pin 9, AND pin 14 is also connected to pin 9. This energizes the headlamp relay and fires all 4 bulbs.

Since you have 3 out of 4 bulbs working correctly, the obvious choice would be to change the lightbulb first.

 

[landcruiser3DP]

I had this issue years ago and it turned out to be some sort of wire failure near the diode, or the diode itself. I ended up bypassing the diode and running my own wiring between the head light relay and light retaining relay. I had the Slee harness at the time too which I ended up deleting.

Do as John @jonheld says and eliminate the Slee harness from the issue first by plugging bulbs directly into the OEM bulb sockets. You’ve already got the wiring diagrams, so if no lights after testing the Slee harness I would get a voltmeter, some jumpers to test with 12v and blue tape and mark the headlight circuit stream from battery to bulb sockets. I like to start at the battery and go towards the component testing for 12v until you find your issue.

thanks man. still learning here with the electrical. do you know where that diode is and where is the "light retainer" relay and what does it do?
lastly i did get things going (mostly) by deleting the slee harness. i'm starting to wonder about my DC refrigerator. the diode prevents voltage from going in some direction? is it possible i blew the slee relays by plugging in this refrigerator?

 

[landcruiser3DP]

Your next step should be to test the connector going to the bulb that doesn't light up.

* Disconnect the wire from the back of the bulb.
* Photograph connector. Take note of the wire colors going to that connector.
* Turn on low beam headlights with ignition off.
* using a voltmeter or test light, probe the low beam (negative) and common (positive) terminals. You should see ~12v across w-b (ground) and r-l (common positive). Try all the combinations to be sure.
* repeat with high beams on, probably across r-y and r-l.

Report back.

thanks. i'm realizing even basic stuff like visualizing that this diagram is showing me two wires from the harness plugging into the bulb has been somehow going over my head. i'll test it....

 

[jonheld]

thanks. i'm realizing even basic stuff like visualizing that this diagram is showing me two wires from the harness plugging into the bulb has been somehow going over my head. i'll test it....

You need to learn how to read a schematic. Below are some helpful resources, but you have to take the time to learn.
There are also countless resources on basic DC electronics.

Google Search

The octagonal symbols are simply splice points as explained in the EWD.

Here is a simplified version of the low beam circuit with everything else removed.
It's a lightbulb. You need +12 and ground.

Here is a simplified version of the high beam circuit with everything else removed.
Again, it's a lightbulb. You need +12 and ground.

 

[jonheld]

delete post please