REPOST -- My previous thread identified the part I was working on as CPU 2 and it should have read CPU 1. I closed the previous thread but could not find a way to delete.--

I fell into a 93 RX-7 that has been sitting for a long time, the previous owner connected the battery backwards doing untold damage.

I have been going through the electronics and repairing them. My current project is CPU 1 in the fuse box.

The electrolytic cap on the PCB had popped and caused damage to a small part of the board. After reverse engineering the PCB I decided its easily repairable but there is one particular component that was completely off the board and the silk screen was removed as well. It is the highlighted resistor in the schematic image. I assume it is a resistor that finishes the voltage divider network as measured by P101. But I could only guess what the value is.

Does anyone here know, or have a picture I can use to figure it out?

 

Was it stored underwater?
Did you replace x1? The reason I ask is that looking at what I think is it's pad on the backside next to the c13 label it just looks like a solder ball.
First thing I would do is grab a meter and start checking some traces in that area to make sure you have continuity.

 

I did not replace it, that is just an ugly bodge done so I could apply power to the MCU and check for life.

Not underwater, but about 200 meters from a brackish river. With the battery connected backwards. Caused all sorts of galvanic corrosion issues, especially in the ECU connectors. Had to completely re-pin the harness and replaced the ECU.

 

You are much braver than most people

 

Or dumber, it remains to be seen.