Maybe Clutch Switch?

[A26B]

Several years ago, there was a similar incident & the owner went through literally everything. It turned out to be a bad battery terminal connection. They were loose, cleaned, tightened & all was good.

[TX '90 ZR1]

Originally Posted by A26B

Several years ago, there was a similar incident & the owner went through literally everything. It turned out to be a bad battery terminal connection. They were loose, cleaned, tightened & all was good.

Thanks Jerry,
I know the connections are tight, but have not cleaned the positive since battery was installed about a year ago.
Before I start tearing out the under dash, think I'll disconnect the battery and see. Best to eliminate all the easy, simple stuff first.
By the way, someone mentioned to clean the key. Did that to no avail.
Really appreciate your input.

[zrfast1]

Do yourself a favor...bypass the clutch switch.

[TX '90 ZR1]

OK.
Cleaned battery connections and re-installed. This did not fix the problem, but the positive terminal did need cleaning.
Gained access to under the driver's side dash.
As suggested by Flyman 27, located orange sleeve with 2 small white wires in it. Disconnected connector and checked for readings between the two wires going into the steering wheel housing. There is no difference in the reading whether key is in place or not, and irrespective of the key position. There is no resistance indicated.
I decided to test the individual wires to ground. One of the wires shows continuity to ground. I have not checked the schematic yet, but I would not think one of these wires should be grounded.
I am going to continue following the FSM procedure, but I am thinking that this wire being grounded may be an issue?
Feedback Please.
Thanks Guys.

[QB93Z]

I have worked on two ZR-1's that had a ground problem related to the wiring under the dash and the steering column harness. The symptoms didn't match your current problem but were very perplexing.


There are two electrical ground connections on the back of the block. Once again I don't know that this is related to you symptoms but may be worth checking. The grounds each have multiple ground wires on a bolt into the back of the block. They are hard to see but the guide is to look above the bell housing bolts on the top right and top left of the bell housing to block connection. On some cars, the left side ground bolt can be reached from above by reaching down below the area of the PCV valves and feeling around the back of the block.


Jim

[5ABI VT]

This happened to me when I was bringing the car home after moving. No prior no start ever. Happened at the gas station on the way home out of all places and times. I ended up push starting it and got it home. Later found out it was the clutch switch. I bypassed it eventually after tinkering with another plug I mistakenly thought was the clutch switch and it solved the problem.

[TX '90 ZR1]

Thanks for the reply Guys.
I will see if I can get to the ground points and check them. Also, I intend to take a look at the clutch switch while I am in there. With the codes I am seeing, it does not "appear" to be the cause of the current issue.

[TX '90 ZR1]

Had a chance this afternoon to do a little more troubleshooting.
Refer to the attached page from FSM to follow my progression.
Code #53 is set on the CCM which indicates either circuit open or shorted to B+.
By following the diagnosis chart I come to a short in circuit #1073. (See Chart)
Is this telling me that the wire in the steering column is shorted and needs repair? To get there I will need to pull the steering wheel and want some back up before I do that.
Also, refer to my post of earlier today about readings I got from wires in steering column.
I'm going to wait for some feedback before I go any further.
Appreciate everything
!CCM Code 53 .jpg

CCM Code#53.jpg

[TX '90 ZR1]

Still trying to figure this out.
Everything keeps pointing to the key lock cylinder or the wires going to it.
I checked the battery connections as suggested.
I checked the clutch switch as suggested.
I cleaned the key contacts in the lock cylinder with electrical contact cleaner.
Cleaned both keys. Both keys have the same resistance and the symptoms do not change no matter which key is used.
Cleared, or attempted to clear, codes in the CCM and ECM. They do not go away. The codes are there next time I turn the key on. I guess this would make sense as the codes are probably being set as soon as the key is turned?
I am now getting some resistance through the two wires going into the column to the key cylinder when key is inserted in the lock position. With meter set to the 2k position, the reading in the lock position is 1.876. This is the same reading I get when checking the keys. The resistance goes away when I move the key away from the lock position. I would think the resistance should be present in all locations??????
Feedback, suggestions please.

[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.