[PhantomSupra1j]

Hey all,

I have a 1992 Mk3 that’s been imported from Japan with a 1jz and r154 combo.

Ive owned the car for over two years now and have not really had any problems with this car other than the twins going bad but no electrical issues at all.

Last night when I was about to leave work and drive home, I went to turn on the combination switch to get lights and I noticed I had no dash lights. Upon further looking, I noticed the taillights weren’t on either. However, the headlights did turn on but the motors did not push the lights up which is the first time that’s happened to me. I manually raised up the lights and tried to rotate the combination switch back to the off position and on again to see if the dash lights and taillights would light up. This time, the headlights didn’t turn on either.

So at this point, I have:
-no headlights
-no taillights
-no dash lights
-the headlight motors aren’t working.

what is working:
-turn signals are working fine

• the door lights are lighting up
• the individual lights for oil pressure, battery and misc other small lights light up on the dash

-hazard switch is working

I have searched the Internet but have only found issues that are found after radio installs or only the taillights aren’t working or the dash lights aren’t working but none of them have the same matching symptoms that I have.


i did check all fuses, which came up good. I also have removed the lower dash and the steering wheel bezel and checked for any noticeable wiring issues which I do not see and also I made sure the combination switch was properly plugged in.

I would appreciate any advice that anyone has to offer. Thanks for your time.

 

[SupraMikeCT]

^ Unfortunately it appears the headlight switch is bad. It controls the headlights, tails and dash lights and switches the headlight motors. It's replaceable separately on the combo switch. The problem will be finding a replacement. RHD shown below:

 

[PhantomSupra1j]

Dang that’s troubling news but that’s the direction I was headed. Thanks for the reply!

 

[PhantomSupra1j]

Does anyone here know where to source Japanese supra parts? I know finding this part will be difficult. I know many sources for Japanese Nissan parts but none for Toyota.

I’ve tried sourcing the part number in the diagram above but I keep finding 84110 with a sub part number such as 84110-20030 but it is a different part.

By chance, would anyone say it’s possible to repair the one I have by disassembling the unit and trying to clean the contacts inside? Or is that not a thing?

Again, I truly do appreciate all the help and advice

 

[SupraMikeCT]

^ I came up with Toyota p/n 84112-80018 for '89- 5/93 for RHD. It's called "switch assy, light control". Did you try Megazip?

Toyota SUPRA Car & Auto OEM Parts | 38377

Your #1 online source of new genuine original OEM parts for Toyota SUPRA Car & Auto (38377) at discounted prices from manufacturers' warehouses in Japan, USA, UAE. Detailed diagrams & catalogues. Fast worldwide shipping to your door. Easy to find parts & order online. Buy now!

www.megazip.net

I figured its been discontinued:

Switch Assy, Light Control, No.1

Buy Toyota - Switch Assy, Light Control, No.1 84112-80018 direct from Japan, 100% genuine parts shipped worldwide.

www.nengun.com

 

[NARFALICIOUS]

Discontinued based on Nengun...
Best bet would be to check between Ebay, Yahoo JP Auctions, and fb.

 

[SupraMikeCT]

So the complete combo switch is showing available for $257 plus shipping on this site below. Google 84310-1B050. That's the complete assy p/n for 89-93 RHD.

Toyota 84310-1B050 (843101B050) SWITCH ASSY, TURN SIGNAL

Toyota 84310-1B050 (843101B050) SWITCH ASSY, TURN SIGNAL. New & genuine Japanese car parts. Fast shipping. Low prices. Request a quote from Amayama Trading Co. online.

www.amayama.com

84310-1B050 - Switch Assy, Turn Signal, Toyota OEM | Megazip.net

84310-1B050 - Switch Assy, Turn Signal, Toyota. New spare parts Toyota from Japan with easy payment system and door-to-door delivery. Tel: +81 34 579 5625

www.megazip.net

 

[NARFALICIOUS]

Glyphs! - JZA70 Supra Light Switch Light Wiper... (yahoo.co.jp)

 

[PhantomSupra1j]

Wow! Thank you guys so much! I’m going to look into those units and make sure they are available and I will report back. Thank you all for your help and recommendations!

 

[PhantomSupra1j]

I ended up ordering it on amayama. I will let everyone know how it goes and when I receive the part.

 

[PhantomSupra1j]

So unfortunately, amayama has sent me a message saying the part could not be shipped. So now I am back on the trail of looking for one. I will look at the other options posted by the members on here and report back with what happens.

 

[SupraMikeCT]

So unfortunately, amayama has sent me a message saying the part could not be shipped. So now I am back on the trail of looking for one. I will look at the other options posted by the members on here and report back with what happens.

^ That sucks! Is it because they don't have it or it's not available?
I tried years ago taking just the light switch apart on a friends 87 but it couldn't be fixed and I'm pretty good with fixing stuff. It had broken black bakelite fragments inside, the circular contacts, the detent ball bearing & spring were all OK. He lucked out and found a complete used one on ebay.

EDIT: Megazip is showing it in their Japanese warehouse but $402!
They were just doing a 15% off code but now it's only 10% off.

84310-1B050 - Switch Assy, Turn Signal, Toyota OEM | Megazip.net

84310-1B050 - Switch Assy, Turn Signal, Toyota. New spare parts Toyota from Japan with easy payment system and door-to-door delivery. Tel: +81 34 579 5625

www.megazip.net

 

[PhantomSupra1j]

They said it was unavailable from their supplier unfortunately.
I was thinking about trying to take it apart to repair it but didn’t want to break it while disassembling it. How did you get your buddy’s switch apart?
Also, I saw it on mega zip and emailed them to see if they could verify the part was available before I ordered it but haven’t received a response. What are the chances that they actually have it?

 

[SupraMikeCT]

They said it was unavailable from their supplier unfortunately.
I was thinking about trying to take it apart to repair it but didn’t want to break it while disassembling it. How did you get your buddy’s switch apart?
Also, I saw it on mega zip and emailed them to see if they could verify the part was available before I ordered it but haven’t received a response. What are the chances that they actually have it?

^ So I found the old switch with the bad light switch and took some pics. I really don't think it's possible to take it apart to repair and actually get it all back together. There is a ball bearing for the switch detent for the 3 positions and a spring and a copper ring that makes contact with the copper contacts on the black part where the 4 wires are soldered on.
There are 4 wires that raise & lower the headlights, turn on the park lights and turn on the headlights. Red, green, white and a shielded wire in pics. It's safe to touch them all together, there is no + & -. Nothing will short out. They are all negatives to control the taillight, headlight and headlight cover retractor relays.
Those 4 wires in pics control everything on light switch stalk.

The white wire is the common wire so it connects to the red, green and the shielded wires as you turn the switch thru its 3 detents.

 

[SupraMikeCT]

The end cap comes off to get inside:

So the end black cap on light switch turns to remove to open and than there is the horseshoe shaped clip that needs to be removed and the spring and ball bearing fly out. I have more pics but I think you get the idea. The stalk removes from the complete switch. it is on a drift pin with a spring and ball bearing in the end. See spring still in at bottom. A ball bearing goes on that spring and the stalk fits in slot in main switch. It's held in by a retainer clip with 2 screws. It rocks on the pin for flash to pass which is a separate switch.

I have more pics should you attempt to repair the switch. I would use the 4 wires and a switch to operate the lights and raise/lower the headlight covers until you find another switch or the light switch stalk.

 

[PhantomSupra1j]

That is a lot of amazing info and I think it’s great that you have no documented it for people who have the same problem in the future. So thank you!
I have taken the stalk apart from the switch and will be attempting to open it this weekend to do the repair pending the response from mega zip. They did email me back and said they have emailed their supplier and will let me know if it is actually available.
I will attempt to repair this one regardless just to see if it is possible it can be done. Im thinking the contacts are possibly pitted or a slight bit of corrosion may be built up so I willclean it with electrical contact cleaner and possible some scotch bright and depending on the amount of material, I may drop some solder onto the contacts and sand them smooth to guarantee positive contact and reduce the possibility of arcing.
I will let you know how it all goes regardless! Thank you!

 

[SupraMikeCT]

So test the following: The White wire is the common ground to the other 3 wires.

In OFF there is No continuity between any wires.
First position from OFF- White wire has continuity to Green wire.
Second position from OFF- White wire has continuity to Green and Shield wire.
Third or last position from OFF- White wire has continuity to Red and Shield wire

White wire to Shield which becomes the Pink wire at pin 2 at connector plug under steering column is Park lights.
White wire to red wire which becomes the V-W wire on M/T and R-G wire on A/T at pin 13 is headlights.

So at the switch assy 2 black connector plugs under steering column you can apply a ground to terminal pin #2 which on LH USA 89-92 is a Pink wire to check that the park and gauge lights come on to prove your light switch is bad before taking it apart.
Apply ground to pin #13 for headlights and ground pin #20 in the longer black "G" connector which is a G-R wire ( Green with Red stripe)


In pic below are the 2 black connectors I circled in red. They are marked as the F and G connector plugs. They are carbody to the complete switch assy.
Terminal pin 2 with Pink line is park lights. Apply a ground - to it and taillight relay should click in, do same to pin 13 and pin 20 on the G connector. You should get headlight relay energized on pin 13 and headlight motors on pin 20.

See 2 to 11 on light control switch K, Pink wire to ground:

Before taking apart the light stalk switch try soaking it upside down ( rotary switch end vertically down in a glass) in 91% isopropyl (rubbing) alcohol. remove it periodically and operate the switch thru its 3 positions and resoak it. I did this on a non-working spare light switch and it worked. It cleaned the contacts without taking it apart. I had no ohm readings before on any wires in any position.

 

[PhantomSupra1j]

So I just did the continuity test for all positions and here are the results:
Test 1:
First position: 2.8ohms
Second position: white to green: 8.9ohms and white to shield:11 ohms
Third position: white to red: 111.5ohms and white to shield: 284ohms.

Test 2:
First position: No continuity
Second position: No continuity on either wire
Third: white to red: 2.5 ohms and white to shield 2.4 ohms.

I’m getting real erratic readings depending on the actual position of the switch in each detent. For example, in the third position, if I move the switch mid way between the second and third position, the resistance decreases.

I am going to soak it in the isopropyl alcohol and will retest. I find it weird to not be getting consistent test results.

 

[SupraMikeCT]

So I just did the continuity test for all positions and here are the results:
Test 1:
First position: 2.8ohms
Second position: white to green: 8.9ohms and white to shield:11 ohms
Third position: white to red: 111.5ohms and white to shield: 284ohms.

Test 2:
First position: No continuity
Second position: No continuity on either wire
Third: white to red: 2.5 ohms and white to shield 2.4 ohms.

I’m getting real erratic readings depending on the actual position of the switch in each detent. For example, in the third position, if I move the switch mid way between the second and third position, the resistance decreases.

I am going to soak it in the isopropyl alcohol and will retest. I find it weird to not be getting consistent test results.

^ I had the same thing, if I wiggled the switch's knob around I would get a reading, than I'd lose it. After I soaked the switch in rubbing alcohol for a day, all readings were consistent and read 0 ohms which they all should be. It's a movable copper disc with 3 fingers that spring out that make contact with the 3 stationary terminals around the perimeter of the black plastic (backlite) with the white wire being soldered on for the center ring contact.
I believe after you soak it and operate it and resoak it, you'll be fine. The copper tarnishes and gets that green patina on the 2 copper contacts.



In pic below the copper ring with the 3 raised fingers hanging around the 4 wires fits down on the metal plate that has 4 holes 180 degrees apart. Those holes are for the detents. 2 springs drop into holes under that plate with a ball bearing on top of each spring, than the metal plate that turns with the plastic switch knob, than that copper movable that fits over the square tab at about 1 o'clock in the left pic. The copper has a 3 sided tab at 7 o'clock in left pic that fits over the metal with 8 holes side tab. They are then stacked together, the 2 ball bearings with springs are pushing up from below the 8 holy metal plateand the 2 ball bearings fall into each hole for the detent. The end black plastic piece at top in pic which has the 4 wires soldered to it with the stationary copper contacts below is what the rotary copper makes contact with when you turn the knob.

^The reason I went thru all the above as you can see how hard it would be to keep 2 ball bearings sitting on top of 2 springs 180 degrees apart from each below the holy metal plate while positionig the the movable copper contact over the metal's side tab and get the recess square slot in the plastic knob indexed correctly and slid on and than getting the last coil spring and the horseshoe retainer clip installed. Never going to happen!

 

[PhantomSupra1j]

That gives me hope lol. Thank you for all the advice you’ve given me and for documenting this! Tomorrow I will redo the test with fingers crossed and I will let you know what happens!