SMAN's Dyno Disater - Updated - Electrical Issues

[BigJeffSS]

I could help you out one night and rule out the wiring. I'm not saying it is a wiring problem but I hate to see anyone waste money on something that may not fix the problem. PCMs go bad but they just aren't as common as wiring issues. What time do you get out of work?

[sman]

Tomorrow I get off at 3, should be home by 330 at the latest.

[sman]

Was just notified, someone on second called in, I have to stay to cover them..... 'cause my day hasnt been long enough... Well im already scheduled for a double tomorrow, so the only day thatd work for me is friday, and in the morning preferably.

Let me know what youve got jeff and ill see if I can change some things around on my end.

Where roughly are you located?

[sman]

Ok, so the way I understand this is that the pcm triggers the ls1 coil like this. The pcm supplies 5v to the trigger wire, this tells the coil to charge, when a spark event is requested the pcm dropps the voltage to 0, and the coil fires.

No matter what i do, no matter what coil I check, I cant get any voltage off of the trigger wire.... I understand that even at idle the computer will be bringing up the voltage to 5 and dropping it to 0 extremly fast, but how am I going to check this?

Ive got a good lead on a pcm, that will probably go quick, so id like to rule this out today if I could. Jeff is probably going to help out tomorrow morning, but id like to fiddle with it today since im not working today.

[BigJeffSS]

Check the supply voltage to the coils... If there isn't any supply voltage check the fuses. Ign1 and Ign2. I would also go through and check all the fuses just to be safe. When checking the ignition circuit voltage are you using pins B and C at the coil? Have you tried to start the car again since you have started messing with the wiring? Spencer feel free to call me if you have questions I will answer them to the best of my ablity. I tried getting out early today but too many emergency jobs can in.

Jeff

[sman]

The supply voltage to the coil is good, pins A and D have enough juice to run a headlight, and when the car is running read 15 v on all 8 coils.

Its pins B and C I cant get anything out of.

I heading out (of the shop) to run some errands and get ready for davison. Ill probably come back afterwards to put my new cluster in and maybe do my valve seals.

[1BADAIR]

pcm controls ground. you wont get power from it

[sman]

Big thanks to Jeff! Frequency appears to be within spec so the pcm looks good, going to steal the coil harness off our Yukon and try it.

[BigJeffSS]

Hope everything is working out good. If the harness clears it up let me know as I can get terminals on Monday or I can take your harness to work and repair it.

[Gottork]

glad things are coming together for your car Spencer