Vats code ?
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Joined: Dec 2005
Posts: 65
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From: Utica In
Vats code ?
An 89 corvette that I am working for a a no start issue has a weird key code. The car cranks but will not start, so I wanted to try a VATS bypass. It will fire (once) then the VATS will kick in, but the car still cranks.
The car has a key that is reading 736 or 737 Ohms. I thought that would be a CODE 3 according to the chart below.
I ordered a CODE 3 bypass and now the car will not crank. The bypass reads 678 ohms. Tried multiple times with 5 to 15 min breaks. When I took the bypass out of the car and reconnected it would crank again. Then I put the bypass back in and no crank. I am now sure it is not a code 3. What your thoughts on how the key reads just outside of code three range, but code three bypass shut it completely down.
Do you think it should be code 4? Thoughts Can the VATS crank, but no fuel or spark?
Thanks
The car has a key that is reading 736 or 737 Ohms. I thought that would be a CODE 3 according to the chart below.
I ordered a CODE 3 bypass and now the car will not crank. The bypass reads 678 ohms. Tried multiple times with 5 to 15 min breaks. When I took the bypass out of the car and reconnected it would crank again. Then I put the bypass back in and no crank. I am now sure it is not a code 3. What your thoughts on how the key reads just outside of code three range, but code three bypass shut it completely down.
Do you think it should be code 4? Thoughts Can the VATS crank, but no fuel or spark?
Thanks
Le Mans Master
Joined: Aug 2000
Posts: 8,838
Likes: 31
From: Australia
Pull the ECM codes and see if it is showing a VATS fault.You may not have a VATS problem
Is possible ECM is not seeing dist pulse that it requires to pulse the injectors .
You say no spark so may be your problem lies there
TPS voltage too high while cranking will shut down injectors as well
........................................ ...
Rare but possible for fuel enable part of VATS module to be faulty so it enables the starter
but not the injectors.
If actually a VATS problem
Two fixes.
Get VATS programmed out of the tune.
Or install this
http://www.bakerelectronix.com/products_vats/
to supply correct fuel enable signal to ECM
NB;
The VATS bypass you have only fools VATS into thinking correct key is in the IGN.
Does not fix problems with the VATS module ( or wiring ) itself
Is possible ECM is not seeing dist pulse that it requires to pulse the injectors .
You say no spark so may be your problem lies there
TPS voltage too high while cranking will shut down injectors as well
........................................ ...
Rare but possible for fuel enable part of VATS module to be faulty so it enables the starter
but not the injectors.
If actually a VATS problem
Two fixes.
Get VATS programmed out of the tune.
Or install this
http://www.bakerelectronix.com/products_vats/
to supply correct fuel enable signal to ECM
NB;
The VATS bypass you have only fools VATS into thinking correct key is in the IGN.
Does not fix problems with the VATS module ( or wiring ) itself
Last edited by rodj; Jan 8, 2012 at 10:00 PM.
Instructor
Joined: Apr 2011
Posts: 180
Likes: 0
From: Warrensburg Missouri
Vats codes
Just thought I'd mention that GM only keeps codes for vats on record
For ten years then trashes the files. I know because I had to
Research vats bypass to get the 15 code values to figure out a
Car I bought at auction with no keys. GM can still cut key blanks
Using the VIN# but that only works provided somebody
Didn't change the locks. Of course if you have the original key
You can use an ohm meter to get the resister value there.
I also found you can buy the vats key blanks on eBay for $5
Instead of $27 at GM but they won't say GM on them. Hope this
Helps someone!
Ben
P.s. each time you use one of the 15 vats code values, watch
To see if the security light goes out, if it doesn't, the ECM will
Lock you out for four minutes then you try again
For ten years then trashes the files. I know because I had to
Research vats bypass to get the 15 code values to figure out a
Car I bought at auction with no keys. GM can still cut key blanks
Using the VIN# but that only works provided somebody
Didn't change the locks. Of course if you have the original key
You can use an ohm meter to get the resister value there.
I also found you can buy the vats key blanks on eBay for $5
Instead of $27 at GM but they won't say GM on them. Hope this
Helps someone!
Ben
P.s. each time you use one of the 15 vats code values, watch
To see if the security light goes out, if it doesn't, the ECM will
Lock you out for four minutes then you try again
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
If you really really want to know what the resistor value is and have a lot of spare time, you can open up the VATS module and find the test resistor on the PC board. It's next to pin W in the picture. In this case the color code (starting from the left) is orange-black-brown-brown = 3010 ohms. The band on the right end is brown for a 1% resistor.
Melting Slicks
Joined: Feb 2011
Posts: 2,322
Likes: 6
From: Los Altos CA
I was thinking of your schematic when I responded in the other copy of this thread.
I would think the 'try 15 different resistor combinations' method would be easier than digging out the VATS module...but your way would certainly yield the right answer.
To the Mods: any way to combine these threads?
I would think the 'try 15 different resistor combinations' method would be easier than digging out the VATS module...but your way would certainly yield the right answer.
To the Mods: any way to combine these threads?
Tech Contributor
Joined: Aug 2006
Posts: 9,933
Likes: 103
From: Peoria Arizona.. Resident Gold Cylon
My local ACE has a key scanner. They also sell the series of blank keys. I mention this as a possible option in you local area just call them in advance. GM wants too much to perform this simple function and yes you can get the key blanks on Ebay as well. GC
