mark kibort

Thanks Z! Yep, all this made it real easy to fix the Tach issue. So, obviosly the tach signal was going to the LH and EZK, but never made it to the Tach, as that wire was cut coming from the LH to the connnector W and subsequentily connector J. I dont know why the holbert car had this issue, but I need to do the same jumper or just wire where it is supposed to go, W11.
I have a feeling that that will be the fix.
Thanks again all, and sorry for the interruption! great drawings. they are going into my archives.

mk

Tails

Davek9,

I have made my voltage divider, brought a PCB, the 10k and 2.2k resisters and a stereo speaker jack for my PC and made the voltage divider as per the drawing and installed the PCB within a plastic box with one inlet with the 'earth' alligator clip and a positive probe and one outlet with two leads connected to a stereo male plug.

I made a drawing to install the second voltage divider circuit, if I wish to use the 2 channels as a later date.

I did my initial test on the output using a 6 volt battery and got the correct output as per the calculator on the net.

Downloaded the Oscope program onto my PC tested it in situ. All appeared to work OK, so now I need to do is test a sensor on my car.

I recently removed the Hall Sensor and cleaned it and at tested it using a analogue volt meter and got a kick when I passed a metal object through the magnetic field.

I will now go into the disconnected plug of the CPU and see what wave form is generated by by the hall sensor whilst cranking over the engine.

Thanks for the help, and I will keep you posted when I have tested the sensor and the total cost of the parts was just over $10.00 and some time.

Are you and JS going to prepare a write up on the Oscope via a PC throuigh thru the sound card using the voltage divider?

Tails 1990 928S4 Auto

davek9

Sounds like you are on your way to start tracing signals cool!

You may just want to plug it all together and just probe the connecter(s) on the CE panel and look for the signal (if you don’t see it then back track). You should be able to get your probe in along next to the wire(s) that is what I did.
I don’t like to power up things with the connection to the computers disconnected unless I have to.

A new thread w/ a write up as suggested would be good, but like I stated earlier on, much of what I learned was from others here in previous threads.

Also I meant to thank Z for the corrections he pointed out, Thanks Z !

DaveK9