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I've determined that something's not right inside the ECU for the circuits on INP11 and tachout.
I have CLT hooked to PC5. The ECU seems to oscillate around 84 degrees F, regardless if the sensor is plugged in or not.
The sensor has a resistance of around 1444 ohms, which does not correlate to 84F from what I understand.
I took a look at the schematic pdf and found that PC5 goes to INP11. Due to not being trained in schematic reading yet, I'm unsure where to look on the board (or which file) to find the Op Amp that controls PC5.

Any pointers here would be greatly appreciated.

Inp11 is one of the special inputs which has a break in the trace. Let me get to a larger device and I will get you the location of the junper which i believe you need to hook.

russian wrote:Inp11 is one of the special inputs which has a break in the trace. Let me get to a larger device and I will get you the location of the junper which i believe you need to hook.

Do you believe that the jumper may've gone out?

Also is there a chance that a ground has been messed up as well?

Do you have reason to believe the the jumper had been installed at some point? I believe it is not installed by default. I believe it would need to be installed if you had a specific need to use INPut11. I'm assuming you are working with a Frankenso, can you check if JP11 has anything installed in it? See below snippet of the schematic.

kb1gtt wrote:Do you have reason to believe the the jumper had been installed at some point? I believe it is not installed by default. I believe it would need to be installed if you had a specific need to use INPut11. I'm assuming you are working with a Frankenso, can you check if JP11 has anything installed in it? See below snippet of the schematic.

There is no jumper. I am using PC5 for CLT, which would mean that I would need to use INP11, and therefore the jumper, no?
I'm using Stefant's 99-00 Miata Frankenso.

Please post a picture of jp11 on your board.

russian wrote:Please post a picture of jp11 on your board.

Wasn't sure how to upload inline (I know photobucket doesn't work amazingly anymore). Image attached.

That jumper will need a wire or solder snot to make a connection. You will not get a signal unless you make this connection.

Unless JP11 ends are soldered together on the back, you have no signal from op-amps tp PC5. You need a 0R resistor or a piece of wire to get signal to PC5.

russian wrote:Unless JP11 ends are soldered together on the back, you have no signal from op-amps tp PC5. You need a 0R resistor or a piece of wire to get signal to PC5.

Okay, the jumper seemed to do it when I played with the board outside the car. Now to issue #2, no more tachout.
I follow the Pe8 trace, and I can't see any physical damage.

In the attached picture, I tried to focus on the jumper. I have no way of magnifying to get a closer look, but it looks like the trace either bends around it, or goes to the jumper. Any ideas?

NBytevenom wrote:Now to issue #2, no more tachout.
I follow the Pe8 trace, and I can't see any physical damage.

"no more" comparing with when? Please post picture of https://rusefi.com//wiki/index.php?title=Manual:Hardware_Frankenso_board#Hi_side - do you have jumpers soldered there to provide +5v into the chip?

russian wrote:

NBytevenom wrote:Now to issue #2, no more tachout.
I follow the Pe8 trace, and I can't see any physical damage.

"no more" comparing with when? Please post picture of https://rusefi.com//wiki/index.php?title=Manual:Hardware_Frankenso_board#Hi_side - do you have jumpers soldered there to provide +5v into the chip?

Okay....so I don't seem to have any wire to tachout. It's possible I never had it there.
Now I feel dumb.

Okay did some more tracing (I'll be honest, I've never done this before, but its intuitive).
It seems that to make wiring easier, there's a wire from the tachout pin, to the W12 pin. Does there need to be a trace in between W12 and the hole right behind it, for there to be a connection between it and PE8?