Help me find the RPM lead (2002 3.4 tacoma 4x4)

Looking for some help locating the RPM lead on my truck.
I don't know why but no one seems to have the answer. Searched all of internet.
So the reason I need this is because I'm installing an AFR gauge that has a capability for rev light indicator. I'm going to do a 5 speed swap and think it would be cool to have.
So far I found that I can hook this up to ECU, OBD2, or and ignition module. But I want to hook it up to the back of the cluster for a few reasons mainly because its closest to the gauge and will keep things more organized.

So here is where I am stuck. I know that the RPM signal comes to the center plug. I found a 97-00 cluster but the wiring is slightly different. From this wright up the signal comes from the black wire located in center plug on the 7 pin side. Looking at the back of the cluster this just leads to a screw?

https://www.tacomaworld.com/threads/how-to-install-aftermarket-tach.227404/


Now on the 01-04 the back looks a bit different. I was hoping to line the two up to see if they go to same location but its not the case.
Here are a few pictures of what mine looks like.


for some reason the center plug and the rpm gauge have no connections.
Let me know what you guys think.

Thanks

 

So this one is coming from the ECU. I need to hook up behind the cluster.

 

Thanks I think I found the page I need. Now if only I knew how to read the diagram.

Looks like the wire I need will be the LG-B?. Is that Light grey with Blue wire?

 

Black wire for RPM is what my 95 model has. Your 2002 is completely different. RPM and Speed are driven by some electronic circuit inside the cluster.



All is driven by four wires on Plug A (plus ground):
A1 (L-Y) - is just power
A2 (G-R) - is the input to cluster from vehicle speed sensor feeding speedometer
A3 (G-O) - is output from cluster to ECU feeding vehicle speed. It is strange but vehicle speed sensor is not connected directly to ECU but it is going via cluster. From the EWD: "The vehicle speed sensor detects the vehicle speed and inputs a control signal to TERMINAL SP1 of the engine control module via the combination meter."
A4 (LG-B) - is input to cluster from ECU (in 3.4) feeding tachometer. In 2.7 that pin is connected to igniter.

A8 (L) on this diagram is just providing a ground to Vehicle speed sensor (via instrument cluster) - another funny design from Toyota.

So what you are looking for is pin A4. I believe it is on the left side in your picture:

 

Im not sure I understand all this schematic correctly but seems I would use the brown connector and hook up to the 4th wire (Light Green with Dark Green Line) in order to get the RPM reading.

 

You got it right.

 

Thanks my guy.
Ill hook it up tonight. Hopefully it all works.

 

What AFR gauge are you installing?I have an innovation gauge with that shift option, I was thinking of wiring it in but didn’t see how to setup the trigger for the light to come on at 5000rpms on the gauge

 

I have the Innovate PSB-1.
I have yet to figure that out. First step is to wire it up correctly and the following steps should be set up threw the gauge. I’m guessing it’s done via computer hook up. An additional wire was supplied for that connection.

 

Okay I found the setup in the menu I have the same gauge and the purple wire I think I have to wire that to the RPM wire from the junction box wire #8

 

Yes you can do that as well. I wanted to use the connection behind the gauge cluster so I didn’t have to bring the wire all the way from the junction box. Already have to much wires in the engine bay. Wanted to hide it better.

 

I grabbed the tach wire from behind the cluster thinking that it would be easier on my '03, but that entailed disassembly of most of the dash including dropping the steering column to get the dash panel out and back in. It would have been a lot easier to run a wire in from the junction box from under the hood.

 

I took most of mine apart wiring the other parts of my AFR gauge so thought it would be a good idea to just go from behind the cluster. Got it all hooked up. Need to just make sure it works.

 

If you tag into the light green with black striped wire on the brown plug, you'll be good to go. I just finished hooking mine up.

 

Have you tested it yet? Or more setting up is required from the gauge side?

 

I tested it in the garage and it works. You will have to set the RPM multiplier for it to read the correct RPM's, but it does work. I set the shift light to come on at 5k rpm and it also works. The gauge only displays real time RPMs when you are programming it. Otherwise, it won't do anything until you hit set limit. The light is damn bright, BTW.

 

Are all the setting accessible from the gauge interface or did you have to us a computer to hook up to it?
I haven’t looked to much into it yet and did see 2 pigtails that looked like was for an external connection of the gauge. Maybe it’s for data loging? Or calibration?

 

I programmed everything through the gauge itself. There's no need to run their software. It may be easier to use a computer though, as programming the RPMs using the buttons were a drag as it would go down 10 RPM per press and the meter starts at 10160 or some high number like that. It took me a good 5 minutes to step all the way down to 5k.

 

Thanks Ill give it a go over the weekend. Ill try the gauge platform first.