Forged 383 LT1 wont start, intermittent DTC 41, how do i test low res opti output?

[MavsFORMULA]

My car wouldnt start as of yesterday. It has no spark at the coil. I found DTC 41 on the pcm. After resetting and cranking it didn't come back. After all the steps in the factory manual, I need a way to test the low res side of the opti.. Apparently its either that or my PCM is fried. I tried another ICM, that is known to be good. Opti just replaced, with used Delco mind you, about 5 weeks ago... Thanks for the help guys, Im dyin here!!!

Nick

[MavsFORMULA]

Basicly, its either the low res signal not being sent from the opti to PCM or the PCM not sending the signal to the coil... Any ideas how to test? Should I be in advanced tech?

[Paulster2]

Check over on Rob's website (www.shbox.com (http://www.shbox.com)). I believe he has some procedures for checking the Opti. You might want to double check to make sure the coil is good as well.

[MoeHorsePower]

Well that code is pretty much telling you that the Opti is the culprit. I have installed Brand New Delco Opti's from the dealer that were bad...

[MavsFORMULA]

You sure that code is opti specific? I thought it told me just what I said.. That either the opti wasn't sending low res to PCM or the PCM wasn't sending signal to coil. I already ordered a new opti yesterday, but I'd like to save the money if my PCM is fried or lost it's program.

What kind of worries me, is I thought there was another low res opti dtc. 16, 42, and one other are the common opti codes. But I too have seen them go with no code. Thanks guys

Nick