gtstcactus

Ok so today I opened the cluster up again....

I pulled off the temp needle thinking I'd put the fuel & temp needles in each others place....

So upon inspecting the temp needles I discover no copper counter weight.... meaning I'd had it in the correct gauge after all..... I still think it's reading 2 notches higher than it was prior to me changing the needles.... So it was removed and put back on... no real change to the reading still a little higher than it was... I really don't see how you can put it back on any different to get it to read what it was...... I mean the connectors and centre post line up where they do so you insert needle accordingly... I don't see how to wind it back a couple of notches or really anyway to fix it.....

I'm happy with the tacho, it's working just fine.... The speedo I think must be ok, I think I was just convincing myself something was wrong there, I matched it off my GPS and it seemed close enough, and I seemed to be at the right speed when in traffic at all speeds so close enough I think... I'll not know how the fuel is working until I fill up...........

All in all I'm happy tho.... regarding the temp needle - so long as you know what normal is be it 2 notches higher than before or not, it's normal that;s they key..... so no big drama I guess...

Perhaps the old needle was reading low...

someone had been into my cluster before as the little post stopping the fuel gauge going to high was broken and rolling around inside the cluster....

Someone had also removed the bulb for the rear brake light out warning light... The tacho needle wasn't sitting right tho it worked too

jrtalbot

I need some help from the contributors to this thread or any other thread for that matter. There is not much information in the SC forums on redoing the needles and cluster lights for a 1993 SC300. I am getting ready to redo all 4 needles using the method described up front in this thread by Lexucan. I am going to attempt to put two SMD LED's on the Speedo and Tach and one each on the temp and gas gauge (boy are they small!!!). I have the cluster pod completely removed and have dug out the old led structures from all four needles. As an experiment I put the ( now LED-less) needles back on their poles and contacts. On the bench, the speedo read 50 mph, Tach read 2200 rpm, temp was mid way between cold and hot and gas guage read completely full. This was with the cluster on the test bench! So it's obvious the needles are finely balanced and I'm trying to figure out how to get them balanced after I install the led's and resistors. Unlike the ES models, the needles cannot be repositioned on their posts because the contacts and the center drive shaft are all mounted inline on a small plastic carrier on the motor assembly. At this point my only option seems to be to use trial and error with adding weights or moving the resistors to get the needles in the same state of balance that they were before I took them off. Any other ideas on how to do this would be welcome. For calibration I can use a gps to get accurate readings of speed, temp gauge isn't critical and I can fill the tank to be sure where that needle should be. But I don't know how to calibrate the Tachometer. Any suggestions here would be useful.
Also on each of the gauge center drive posts, there are two contacts, on has a small brass (yellow colored) base and the other has nothing at the base. Which one is the positive terminal?
I am also replacing the back lighting with LED bulbs. Does anyone know which are the positive and negative contacts on the circuit board that the back lights plug into?
Before I took the cluster out, I had a problem with the tach and speedo not working until I smacked the dash. This problem was worse in hot weather. There's a lot of info on this in the LS forums and with the LS it seems to be related to some sticky material getting on the lower stops for the needles. But I can't see anything like that on mine. Any info on this specifically for the SC models would be gratefully received.
Lots of questions, and any suggestions on how to proceed will be welcome.
Its obvious nobody is reading this thread anymore, but I'll answer some of my own questions for posterity and maybe to help others.
first on soldering the LED's, they are very very small and you will need something to hold then. I got a spring loaded needle nose tweezer, soldered one end of the resistor to the positive side and then was able to use the the tweezers again to solder the 30 gauge wire wrapping wire to the other end. Having the resistor on one end helps to find the LED when you drop it. I was able to solder two LED's together for the speedo and tach and used 2 resistors in each needle. used 1 LED for the temp and gas needles. A tip on this is that the needles become transluscent about 1 mm from the tip (the tip is opaque), so you need to place the LED's about 1 mm or so from the tip to maximize the glow spot. For this soldering i bought a soldering iron with a replaceable tip , very fine angle and very small tip.
With respect to the positive and negative terminals for the needles, there is no set pattern, but the speedo and tach are the same but different from the temp and gas needles. I cant remember which is which, but if your existing LEDs have any life left in them at all, you can use a 9volt battery to light them up and then note which is the positive terminal in the needle. Otherwise good luck, its trial and error. I made 3 errors to start with and had to go back in a re-solder the wires in the needles.
I think I have found the solution to the sticking needles. I can't be sure of the cause, but I drilled two very small hole in the "zero" position on the tach and speedo dials then inserted a 1 cm x 1 mm roll pin to act as a "zero stop " for the needle. Super glue to fix it in place. For 1 month now I have had no needles sticking at zero. some else on the website suggested this fix and it seems to work.
For the backlighting, I used the LED's from Superbrightled's that have 3 SMD's and are like a basic circuit board (info elsewhere on the site). They are a bit loose in the sockets so they need the contacts to be bent a little. They are pretty good but have slight hot spotting. So I added reflective aluminum tape to the curved and flat surfaces in the back of the cluster. It helps somewhat but it's not perfect. I'd say 90% good. Not going to mess with it anymore.
I also added colored LED's for the turn signals, hi beam and cruise indicators as they were a little dim. Finding +/- on those takes trial and error.
Now for positioning of the needles after all this work. the needles can only be placed back on their posts in ONE FIXED POSITION there are no adjustments that can be made. For me this meant that the speedo and tach were accurate. But indicated temp and gas were not correct. The reason for this is that the new additions of 2 resistors into the needle upsets the balance. I decided to accept that the temp needle read a bit low but added a counterweight to the gas needle to make it read higher than after the modification with the resistors. If your speedo and tach read in error , then you may also need to addd counterweights. Be aware that these adjustments may take some time and are not as easy as seems from reading the threads on the site. As a suggestion the use of two resistors for this modification seems a bit like overkill and one 1/4 watt resistor may not need the fiddling about with the counterweights.
Finally, for anybody attempting this job, be prepared to remove and install your cluster multiple times to get it right. I ended up putting to silicone grease on the connectors at the back of the cluster as they were quite difficult to release especially the one on the right as you look at the cluster in the car. But after 3 months I think i've got it all fixed. Thanks to all on this site in the various threads. Also thanks to Lexucan for the individual help. If anyone wants to get specific details of the materials I used, like LED's , soldering iron, wires etc, PM me and I will respond.

plosey93es

I know this is a bit of an old post but such a good one that I want to try it. I just got 93 ES300 with 125k. The needles don't illuminate at all so I don't know what stock looks like and how it compares to this mod. Can anyone post a stock pic of the entire instruments illuminated so I can see the difference. That would be great, thanks.

Patrick

TaninAuto

For $84 you'll be much happier with our DIY needle boards.

https://www.taninautoelectronix.com/...needle-boards/