SCwidaGTE

can someone please explain to me why there is such a big secret about this? what kind of a person are you people to find out information about something that can help alot of people, but keep it a secret? like, what is the big deal. isn't the point of an online community to help people out and share information? those of you who know how to get the tach working and won't say, are just ignorant fools who rely on the ability to withold info to make yourselves feel more important than you really are. once i figure this out for myself, i will be sure to post a sticky up with pics on exactly how to do this so there will be no more secret about it. no one will get rich off this, and it really is just common wiring and electrical knowledge. so, you are not any more important than the others here, even though i'm sure you feel that way. but, i will have a sticky posted soon enough on exactly how to do this mod.

kaosman

Okay guys here's the deal. I completely ripped apart the cluster, and isolated the tach input, 12+ and ground down to the tach daughterboard. IG- (the tach signal) goes into pin 2 of a 16-pin IC, after passing through a resistor. The tach signal goes straight to this resistor through the main circuit board of the cluster. At this point I'm 100% positive that the ignitor output needs to be inverted to a negative signal in order to get the tach to work. But I'm not sure how to *safely* go about it.

Dew23

iTrader: (1)

For all who are upset about me not posting in this thread, i have a new camera on order and i am waiting for the car to come back from the shop. I did not have to start this thread my temp guage and tach work perfect and the other we have done work as well.

nasc300

2.5tsoarer

iTrader: (3)

from this pic the resistor between looks disconnected, is this correct ?

5spdSC300

iTrader: (1)

Didn't mean to come off upset if that was directed towards me. It just look like the thread was dying and we were still confused on what to do. I really do appreciate you stepping up and posting the info since it seem like a big deal to keep this info a secret by other members for some reason .

kaosman

I just did this mod tonight and it works...although I had to bypass a different resistor, my board is different. It shouldn't matter if you cut the resistor or not. I left mine intact.

nasc300

Now anyone know how t do it for a Supra MKIV GE to GTE swap

kaosman

It may be pretty easy...that resistor that's being bypassed above, that's for the tach signal. All you need to do is find the tach wire going into the cluster, follow it on the circuit board, and bypass the resistor on that trace with a wire. That's what I did with my cluster...my board is different and you have to jumper a different resistor (R73).

nasc300

Where did the other thread go with the pic of the other cluster.
It was not merged as far as I can tell.
it was here:https://www.clublexus.com/forums/sho...d.php?t=213164

kaosman

Looks like it was deleted...probably by the original poster. Which cluster were you looking for? If it was the pic I posted, here you go...

blksc300mt

so still nobody has shown how to fix the temp gauge...without ripping off the needle! would anyone care to show how to make it work correctly without using the 330 ohm resistor, since it does not function correctly with the 330 ohm resistor installed.

Supra Dr

iTrader: (14)

Agreed, the gauge is annoying. the response time is beyond slow. i tried playing around w/
different resistors & so on. then it just got back burnered as a low priority. i'm using the msd
tach adaptor also.

when Dew gets his new camera & continues his thread to resolution. i'll fix the gauge &
probably remove the tach adaptor.

So no i'm not hiding the secret, just living w/ it.

john

Jzz31turbo

To make the tach 100% accurate, you have to replace 4 resistors on the back of the cluster. If i ever get around to it, ill post up what to do

ConSynX

iTrader: (1)

just bypassing that resistor R109 seems pretty accurate
once i get an intake i'll see if it cuts at the rpm it should
(stock airbox sux)