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1990 vats question

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Old May 5, 2014 | 03:07 PM
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Default 1990 vats question

Okay does the ccm need the vats code and then it interprets and sends signal to ecm or does the ecm only see the signal?

I have seen vats decoder boxes in earlier gm cars but no mention of it in 90 manuals.

Don't have problems just selling ecm and ccm so need to know who needs the vats code

Thanks
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Old May 5, 2014 | 04:00 PM
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Originally Posted by My1991
Okay does the ccm need the vats code and then it interprets and sends signal to ecm or does the ecm only see the signal?

I have seen vats decoder boxes in earlier gm cars but no mention of it in 90 manuals.

Don't have problems just selling ecm and ccm so need to know who needs the vats code

Thanks
VATS is stored in the CCM. The buyer will need the VATS key information. It can't be changed. If you don't know the VATS information it will require a VATS Interrogator to be used to determine the information.

Last edited by WVZR-1; May 5, 2014 at 04:02 PM.
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Old May 5, 2014 | 04:05 PM
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Or it can be bypassed by the use of a resistor to give the correct read at the key switch, or program it out of the ECM's memcal, and bypass starter relay.

www.vatssucks.com
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Old May 5, 2014 | 04:13 PM
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Originally Posted by MrWillys
Or it can be bypassed by the use of a resistor to give the correct read at the key switch, or program it out of the ECM's memcal, and bypass starter relay.

www.vatssucks.com
Regardless the VATS resistance needs decoded - now if there's a "super secret" solution to determine that then I'd be interested in being made aware of that. If the resistance is "unknown" I believe it would certainly be a more difficult sell.

BTW - there's many that don't feel that VATS Sucks but you're certainly the first to mention.

Last edited by WVZR-1; May 5, 2014 at 04:15 PM.
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Old May 5, 2014 | 04:35 PM
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Originally Posted by WVZR-1
Regardless the VATS resistance needs decoded - now if there's a "super secret" solution to determine that then I'd be interested in being made aware of that. If the resistance is "unknown" I believe it would certainly be a more difficult sell.

BTW - there's many that don't feel that VATS Sucks but you're certainly the first to mention.
I'm not looking for a pissing contest if that's what you're interested in?

You know as well as I do that a simple resistance module purchased from flea bay, or wherever is capable of bypassing the key switch at the steering column. If the memcal is reprogrammed, and the starter enable relay grounded, and or bypassed then there's nothing for the CCM to interfere with.

Honestly, do you really think this is the first time this issue has come across this board? Maybe since yesterday. Whether for or against I was simply pointing out more options that you left out.

Have a wonderful day sir!
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Old May 5, 2014 | 04:36 PM
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Not to mention his post is a bit vague as to his intention, and or need?
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Old May 5, 2014 | 07:03 PM
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Why is it vague?

I asked if buyer of my ccm needs vats value. Another wants my ecm.

I have that vats key but according to some of you the ccm buy is screwed without key.

So sending to him

Thanks
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Old May 5, 2014 | 07:14 PM
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Originally Posted by My1991
Why is it vague?

I asked if buyer of my ccm needs vats value. Another wants my ecm.

I have that vats key but according to some of you the ccm buy is screwed without key.

So sending to him

Thanks
I believe I understood the post. Is a CCM with the key or known resistance worth more than just a CCM or is it of no consequence. If you were parting a car the key might be of significant value for the sale of a column. If you've 2 keys - one for each OR the resistance value is the only requirement for the CCM. The actual key isn't but in the past I've just taped a Known key to the CCM to keep track of and send with - as you've mentioned doing. I think you did the buyer well!

Don't know that it's important in your sale or not but the mileage and the VIN are locked in the CCM also.

Last edited by WVZR-1; May 5, 2014 at 07:20 PM.
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Old May 5, 2014 | 07:44 PM
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Originally Posted by WVZR-1
I believe I understood the post. Is a CCM with the key or known resistance worth more than just a CCM or is it of no consequence. If you were parting a car the key might be of significant value for the sale of a column. If you've 2 keys - one for each OR the resistance value is the only requirement for the CCM. The actual key isn't but in the past I've just taped a Known key to the CCM to keep track of and send with - as you've mentioned doing. I think you did the buyer well!

Don't know that it's important in your sale or not but the mileage and the VIN are locked in the CCM also.
Thank you. Yes I know mileage was stored in it, didn't know vin was though.

Buyer said he would have key read and text me back the code. I just wasn't sure if the value of key would help him since some cars have a decoder box alone for vats. I figured since I didn't see a decoder box figured the key would save him on nightmares.
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Old May 6, 2014 | 04:17 AM
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The function of the VATS module was moved into the CCM in 1990.

I have heard that there is a method to get the CCM to "learn" the key resistance. It uses a different system (ADC converter) than the older VATS module (voltage comparator), so I believe that this is possible. Found it! Here ya go:

http://my.cardone.com/techdocs/pt%2077-0011.pdf
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Old May 6, 2014 | 04:41 AM
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Originally Posted by Cliff Harris
The function of the VATS module was moved into the CCM in 1990.

I have heard that there is a method to get the CCM to "learn" the key resistance. It uses a different system (ADC converter) than the older VATS module (voltage comparator), so I believe that this is possible. Found it! Here ya go:

http://my.cardone.com/techdocs/pt%2077-0011.pdf
Just which procedure do you "suspect" will work?

An "out of the box" CCM, reconditioned (properly) or new can learn an existing set of keys and it's suggested to use 2 keys for the learn. Using a single key "twice" does NOT assure that another second key or a service key will work. This procedure is for CCM vehicles

The VATS, VIN and mileage can't be "overwritten" but only written to after being properly erased.

The OP did his buyer well

Last edited by WVZR-1; May 6, 2014 at 04:59 AM.
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