Maybe Clutch Switch?

[TX '90 ZR1]

Originally Posted by -=Jeff=-

Yeah, that was in the FSM right? I was quite sure it was there

You are correct Jeff. It is in the FSM and there are some explanations available by doing a Google search.

[-=Jeff=-]

any more progress?

[TX '90 ZR1]

Originally Posted by -=Jeff=-

any more progress?

Not yet. My plan is to come up with something to simulate the key resistance and plug it into the key lock harness.
Just need a little time, which I have been short of the last couple of days, to chase down what I need to rig it up.
Main problem is that I am a little farther than in the middle of nowhere from anywhere!!
I'll figure something out and keep everyone updated.

[Paul Workman]

Originally Posted by Flyman 27

A year ago I was having a similar problem, it turned out to be the resistor readings in the connector to the key, that wasn't too hard to replace (videos on YouTube).

This past spring I was having another no start issue that I was totally lost on. -=Jeff=- came by and after checking connectors & switches, jumpered over the clutch switch and it started right up with no issues since.

Maybe -=Jeff=- can pipe in here and tell you where the connector is and what wires you jumper. The Conn was on the LH side, under the Driver's side hush panel. I didn't see where the conn was from, so I can't help you there. -=jeff=- was very systematic in his approach and saved me hours & hours of a frustrating problem I couldn't chase.

OP: Jeff's method of methodically troubleshooting is THEE way to solving electrical issues systematically. It's fine to have a number of suggestions of things to check, but randomly "stabbing in the dark" is no substitute for efficient, logical circuit tracing and verification along the way. Ya don't wanna go down that path, IMO.

[TX '90 ZR1]

Originally Posted by Paul Workman

OP: Jeff's method of methodically troubleshooting is THEE way to solving electrical issues systematically. It's fine to have a number of suggestions of things to check, but randomly "stabbing in the dark" is no substitute for efficient, logical circuit tracing and verification along the way. Ya don't wanna go down that path, IMO.

Thanks Paul,
That is what I am trying to do. I have followed the FSM trouble shooting and intend to verify before randomly changing parts.
I have checked things that were suggested, but with the codes I am getting and the FSM procedure telling me it is in the key lock circuit, I am going to follow this path until it is either verified or proven incorrect.
All I have in it to this point is my time which is generally not worth much!!

[TX '90 ZR1]

This one has been a journey!!
All the indications I was getting from codes and tests indicated the key lock circuit in the steering column. Followed the FSM troubleshooting chart. Sometimes I would get a higher voltage reading than recommended, so chased that side also. This was a slight discrepancy. ie: 5.2v vs 5.6v.
As I could not source something to make a resistor out of locally, I had to order what I needed. Got it and verified correct resistance for my car. Hooked this up and still had the same issue. What the hell? Security light still stays on steady and I can't get the code to go away in the ECM. The CCM codes cleared.
At this point I am trying to find enough hair on my head so I can pull it out!!!
Looks like I'm on my own now, so start checking all of the security system components. I started by trying to remember anything I had done to the car recently that might affect this. I had cleaned the inside of the rear glass and a defroster wire came loose. I had reconnected it. This did not sound like a security issue, but checked anyway.
Had also cycled the door locks while checking the security system operation. Everything in the drivers door checked OK. BUT, and here it is!!! The passenger door lock was not making good contact.
Who would have thought??
Anyway, it is operating properly now. Now I can go on to doing little picky things to it and not have nightmares about wiring schematics.

[zrfast1]

.....well Ill keep that in the memory banks. Good for you. Now enjoy the car...you earned it.

[TX '90 ZR1]

Originally Posted by zrfast1

.....well Ill keep that in the memory banks. Good for you. Now enjoy the car...you earned it.

Thanks. I think any tidbit of information is worth storing in the memory bank. Whenever I run across something I try to post it for others use. I know I scour the threads for information so turn about is just good manners.
To be clear, the initial no-start issue was the key lock cylinder in the column. Erratic resistance readings. I still have it bypassed and will change it sometime. The passenger door lock issue arose while in the midst of troubleshooting the original problem. It did not raise it's ugly head until I had eliminated the original problem.

[zrfast1]

Originally Posted by TX '90 ZR1

Thanks. I think any tidbit of information is worth storing in the memory bank. Whenever I run across something I try to post it for others use. I know I scour the threads for information so turn about is just good manners.
To be clear, the initial no-start issue was the key lock cylinder in the column. Erratic resistance readings. I still have it bypassed and will change it sometime. The passenger door lock issue arose while in the midst of troubleshooting the original problem. It did not raise it's ugly head until I had eliminated the original problem.

You mentioned your background is in aviation. I (we) see this everyday as everything is not what it always seems to be. Apply troubleshooting techniques
and just when you think you have it, you dont. Been there many times. At least it showed its ugly face when you corrected the main issue. Broken wires are the worst..at least you didnt have that! Cheers

[TX '90 ZR1]

Originally Posted by zrfast1

You mentioned your background is in aviation. I (we) see this everyday as everything is not what it always seems to be. Apply troubleshooting techniques
and just when you think you have it, you dont. Been there many times. At least it showed its ugly face when you corrected the main issue. Broken wires are the worst..at least you didnt have that! Cheers

Yes, most of my mechanical background is in aviation. I have the A&P and used to have the IA, but mostly I was the "guinea pig" that got to test the limits and try to make them break! As I say, and others as well, " Flying is hours upon hours of boredom interrupted by moments of sheer terror!".
Here's a pic of one of my Reno races.
Reno '90.jpg