DEREKC

How do you power up a 94 SC300 cluster for benchtesting?
I need to find out the odometer reading and test for polarity for LED bulbs.
Someone selling the same cluster on ebay shows it is possible. Here is the photo of his:



My cluster is here:

CatManD3W

iTrader: (18)

I would like to know the same as well.....

oldManTan

yea same here, i wanna do some work to mine.

BlackIRON

Bump i need to know.

Kris9884

iTrader: (7)

You need to find which pin is the power and which is the ground, then connect a 12v power source to it. The positive tends to be gray or red, and the ground is always black. Just look at the harness and look at which pin it would connect to on the cluster. In a perfect world the service manual should have this exact pinout.. You can even use your car battery if you just run a wire from it to that pin.

Here's the pinout I found online for the 92-94 cluster.

https://www.clublexus.com/forums/att...emp-sensor.gif

roc

iTrader: (7)

bump this,need to know this also

PseudoK

the answer is right above your post!

logix7

bumping an old thread. would like to know this. kinda hard to tell from the diagrams in the manual

logix7

does anybody know?

GrantReid

bump again.
how about the colour of the wires maybe?

blood

so the bulbs was out and needed to figure out what bulb is blown so using jump pack and 3 alligator clips 2 ground 1 positive as you see in image and cluster is working and is you used 1 ground not all of them just 2-5 like check engine oil and when using 2 ground it will light and you can disconnect the tow connector so you can flip the board and you can remove the bulb and test is it working and there is 2 types of bulb and socket small and big big one will not win in small but small one will fit the big one and work






middle plug

GrantReid

AND THERE YOU HAVE IT FOLKS!!!!

Thank you Blood for a very thorough and complete answer with photos included. That is more than I would have expected.

Well, actually as nice of an answer as you provided, I would still have to flunk you for being too slow with it (10 years).

blood

O. L. T.

iTrader: (17)

The answer has been on the forum for 15 years, but nobody searches unfortunately. As a bonus the easier way is in the same post which is to grab power at the ribbon cable on top by the diode row rather than the middle plug which will give you access to the diodes that you need to check because they control power to the bulbs on the board. in blood’s pic grabbing power at the middle ribbon plug doesn't give you the ability to check power at the diodes on a different plug.

while this way will show you if power passes through the diodes, it wont tell you if its the bulb or the diodes that are bad. (Its usually bulbs). The diodes are not on the same plug, but they are in a row in the pic above. In the original post about this, those diodes are circled in a Red circle showing which ones they are.

its all in the FAQ stickied to the top of the forum. Thread is “everything about the cluster” and “true ice blue caps for the cluster” and was done in 2004.

I’m glad you figured out what you were looking for blood,and it will likely help some who dont use the faq we provided. I’m glas you were able to get your issue fixed.

blood

i dont know how to read the diagram this is why i did it like that