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Old Jul 29, 2014 | 04:01 PM
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Default Security Light On

Started the car this morning and the security light remained on. 2004 convertible. Everything appears to be working. I have no owners manual nor maintenance manuals. Any ideas?
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Old Jul 29, 2014 | 04:23 PM
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Pull the codes and then post what shows up.
Here is a link for owner manuals ( I have a better one but can't locate it right now).
Good luck

found it ==http://www.corvetteactioncenter.com/specs/c5/2004/2004corvette.pdf

Last edited by Sonny71; Jul 29, 2014 at 05:41 PM. Reason: update
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Old Jul 29, 2014 | 05:57 PM
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Is your convertible storage compartment lid closed all the way?

Last edited by JR-01; Jul 29, 2014 at 09:50 PM.
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Old Jul 30, 2014 | 04:52 PM
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Sonny71,
Pulled the codes and there're several. Without listing all, here are the modules; PMC. BMC. LDCM and RDCM. No other modules has codes.

I've only had the vette for a few months so I do not know any of the past history.

Thanks for the info.
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Old Jul 30, 2014 | 04:59 PM
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Sonny,

Found this on the code list; P1631 Theft Deterrent System Password Incorrect. How is that corrected?
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Old Jul 30, 2014 | 06:14 PM
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Try another key or buy a new key. As the pellet wears on the key this can happen. It caused my car to not start a few times because there wasn't good contact with the key pellet. I bought a new key and it never happened again.
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Old Jul 30, 2014 | 07:21 PM
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Originally Posted by flier32
Sonny,

Found this on the code list; P1631 Theft Deterrent System Password Incorrect. How is that corrected?
That's a 'History' code: if it was current the car would not start or even crank. According to the FSM, it will clear itself after 40 consecutive warmup cycles without a malfunction, or it can be cleared with a Tech2 scan tool. Probably wouldn't hurt to try to clear it at the DIC, but I wouldn't be surprised if this is one that can't be cleared that way. At some point someone attempted to start the car with a bad (or wrong) key.
Originally Posted by got-20z
Try another key or buy a new key. As the pellet wears on the key this can happen. It caused my car to not start a few times because there wasn't good contact with the key pellet. I bought a new key and it never happened again.
The key he's using now is ok or the car would not have started, but it wouldn't hurt to have a spare on hand.
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Old Jul 30, 2014 | 07:55 PM
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Originally Posted by Lee DeRaud
The key he's using now is ok or the car would not have started, but it wouldn't hurt to have a spare on hand.
When my security light would come on and stay on while driving that was my issue. The worn key and pellet caused the light to come on and a few times after I would get out of the car and get back in and try to start it, it wouldn't do anything. Then after about 10 minutes, it would start. A new key fixed it.
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Old Jul 30, 2014 | 08:36 PM
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Originally Posted by got-20z
When my security light would come on and stay on while driving that was my issue. The worn key and pellet caused the light to come on and a few times after I would get out of the car and get back in and try to start it, it wouldn't do anything. Then after about 10 minutes, it would start. A new key fixed it.
Did you read what I wrote above? It takes 40 consecutive start cycles without a glitch for the light to clear by itself. That takes awhile for most people.
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Old Jul 31, 2014 | 04:02 PM
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Thanks All, I'll have a spare handy. MARKED SPARE of course.
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Old Jul 31, 2014 | 04:29 PM
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Originally Posted by Lee DeRaud
Did you read what I wrote above? It takes 40 consecutive start cycles without a glitch for the light to clear by itself. That takes awhile for most people.
40? What kind of idiotic engineer came up with that number?
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Old Jul 31, 2014 | 06:42 PM
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Originally Posted by JR-01
40? What kind of idiotic engineer came up with that number?
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Old Jul 31, 2014 | 07:00 PM
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Originally Posted by JR-01
40? What kind of idiotic engineer came up with that number?
ET to the white courtesy phone please...

<edit> 42 would have been hilarious (42 is the answer to the universe for those who don't know).
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Old Jul 31, 2014 | 07:12 PM
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Originally Posted by 66dts-v
ET to the white courtesy phone please...

<edit> 42 would have been hilarious (42 is the answer to the universe for those who don't know).
I picture a bunch of GM engineers sitting at a table trying to come up with a number. A reasonable guy suggests 5 to 10, but his supervisor wants more. Much more. That will bring the cars in for more service calls. Many more.
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Old Jul 31, 2014 | 11:15 PM
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Originally Posted by JR-01
I picture a bunch of GM engineers sitting at a table trying to come up with a number. A reasonable guy suggests 5 to 10, but his supervisor wants more. Much more. That will bring the cars in for more service calls. Many more.
I'm sure one of the considerations was how many times a thief might try with each key value before giving up. I'm sure it wasn't advertised that 40 was the magic number. It is, after all for security.
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Old Aug 1, 2014 | 12:30 AM
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I had this same problem on my 04. If you think the key is "too worn" you can test the resistance across the key's resistor (the "chip") Click here for DIY. Once you know that you can go to any quality locksmith, buy the correct number and get it cut for about $20+.

I also cleaned my ignition switch using This DIY from Bill Curlee. This ultimately fixed the problem for over 4 years and counting.
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Old Aug 1, 2014 | 01:47 AM
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Originally Posted by 65GGvert
I'm sure one of the considerations was how many times a thief might try with each key value before giving up. I'm sure it wasn't advertised that 40 was the magic number. It is, after all for security.
Not sure you understand: it takes 40 successful starts to clear the code/light. It doesn't disable the car for 40 attempts.
(And no, they didn't advertise that number, but they did put it in the FSM...pretty sure a thief could look it up if it mattered.)
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Old Aug 1, 2014 | 04:18 AM
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Forty is the number that shows up most often in both the Old and New Testament. It represented a generation back in the day which was considered a long time. Perhaps the engineer who devised the "40 successful startups" was religious. Please understand this is just a theory I came up with over breakfast and may or may not be the complete truth.
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Old Aug 1, 2014 | 05:16 AM
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Forgive me if I missed something earlier as I haven't had time to go through all the posts.

The way the system works is when you put the key into the ignition the computer checks the resistance in your chip on your key. If it gets the right answer it allows fuel to flow and the engine starts. You geta security light until the chip makes contact.

This used to be a problem a few years ago but there dont seem to be as many examples recently.

Things to check:

Try the spare in case the primary key has a chip problem.
Clean the key giving the problem to make sure the resistor is being read.
Squirt electronics cleaner into the barrel to clean up those contacts (probably wont work).
If you hang heavy stuff from your key ring take it off. If you have a worn barrel it may be causing the chip to lose contact. This often means the car starts OK but the security light comes on once the car is going.

If all that fails you can cut a new key but find out which resitor you need
If all still fails you're into rebuilding or replacing the ingnition switch in line with Bill Curlee's advice.

HTH
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Old Aug 1, 2014 | 07:30 AM
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Originally Posted by Lee DeRaud
Not sure you understand: it takes 40 successful starts to clear the code/light. It doesn't disable the car for 40 attempts.
(And no, they didn't advertise that number, but they did put it in the FSM...pretty sure a thief could look it up if it mattered.)
But, it does let you know for 40 tries that someone tried the wrong key. I believe it can be cleared with the DIC, but haven't cleared that specific code. I also understood that if the security light stayed on the car wouldn't run, sounds like that is not the case here. I'm not sure what the value of the vats system is if it lets the car run with the wrong key.
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