ISC Coil Questions

[90projecttalon]

Ok, I have a 1990 Eagle Talon TSI AWD. I took the ISC off and tested it, and 3 of the 4 coils are reading O.L. (open lead). Previously, I did not know that the ISC was bad, and it fried the IC107 in my ECU. I have replaced that now, and have a new ISC on order.
My question is, I want to make sure there is no short in the actual wire harness itself. I used my ohm meter to test it two ways.
The first way I tested it was be using the chassis as a ground and probing the pins going into ECU from the main harness themselves. They read 11.8 ohms across the board.
Now when I tested from one end of the connector to the other, they were reading O.L. Is this normal?

Is there another way to test to make sure that there is no short in the harness from the ISC to the ECU?

Sorry for the long story, and thanks for the help in advance.

 

[mark 91 tsi]

If you disconnect the harness from both ends you can go to one end of the harness and check for continuity between each of the wires. If you have continuity you know that the wires are touching somewhere.

 

[ramsack]

Open circuits won't fry the drivers in the ECU, shorts will. Disconnect the ECU, the IAC, and at the ECU end, test for shorts between each of the 6 wires.

 

[thomyd]

check the isc it self for ohms. if alls good move on to wires.

 

[miguelmcv]

I don't think the ISC can build enough current to fry a line (Wire).

If after replacing the ISC, you would off still have problems, then I might say that a line is not good.

If everything is working good after replacing the ISC, then I would say, you are good to go.

Just my 2 cents.

 

[ramsack]

He tested the IAC. The coils were open. Open circuits will not fry the drivers in the ECU...there is zero current running through them. There has to be a short in the wire.