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Discussion Starter #1
I bought my 94 fleetwood in August 2015, that october I bought and installed a vats bypass from ebay. Lately when I go to start the car it acts like it tripped the vats system but the light doesn't stay on like it did befor the bypass. Usually takes a few times of removing and inserting the key before it will fire ul.
 

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Just spitballing here, but you may want to bypass your bypass. Maybe there is an issue with how it was installed or something not working right with it. Why did you bypass it in the first place? Was it due to similar issues and maybe that issue is still present? Again, just some wild guesses.....
 

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Discussion Starter #3
Just spitballing here, but you may want to bypass your bypass. Maybe there is an issue with how it was installed or something not working right with it. Why did you bypass it in the first place? Was it due to similar issues and maybe that issue is still present? Again, just some wild guesses.....
the same reason I assumed everyone else does it, it started to do the problem where you start the car and the system woul trip and make you wait to start. I bought one of those pre-assembled bypass kits off eBay that you just plug directly into harness for the vats
 

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I bought my 94 fleetwood in August 2015, that october I bought and installed a vats bypass from ebay. Lately when I go to start the car it acts like it tripped the vats system but the light doesn't stay on like it did befor the bypass. Usually takes a few times of removing and inserting the key before it will fire ul.
Now that you by-passed the VATS,if you can put the key into the lock cylinder and it turns then it's not a key or lock cylinder issue.Sounds like the VATS module and or VATS relay may be acting up.More so the relay than the module imo.

Jim
 

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Discussion Starter #5
Now that you by-passed the VATS,if you can put the key into the lock cylinder and it turns then it's not a key or lock cylinder issue.Sounds like the VATS module and or VATS relay may be acting up.More so the relay than the module imo.

Jim
How would I go about fixing that? I have discovered that 75% of the time if I turn the key to the on position and wait five seconds to crank it will usually start.
 

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I bought my 94 fleetwood in August 2015, that october I bought and installed a vats bypass from ebay. Lately when I go to start the car it acts like it tripped the vats system but the light doesn't stay on like it did befor the bypass. Usually takes a few times of removing and inserting the key before it will fire ul.

Phil,
In re-reading over your original post,almost sounds like it could be another unrelated to the VATS issue? Especially since you say the light does not come on now when you're having the starting issue.
Jim
 

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I just went through this last week.

My pass key light was blinking though.

If you want to bypass the vats module completely see his post I made in the pass key/vats thread:

http://www.impalassforum.com/vBulletin/11949745-post210.html

It was a bit of an after thought so that's the best how to I could make.

IDK what kind of module you got off ebay. Do you have a link? Seems most of them are just the resistor trick...it's not a vats bypass it's just a key bypass. The vats module still controls whether or not the car will start...all you're doing is making it think the key is inserted. Apparently the modules like to fail as I found out recently.

NSS could be the culprit as well and so could the ignition switch or the wires leading to it. Apparently those are also a common point of failure. I would think more common than NSS.
 

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Discussion Starter #9
I just went through this last week.

My pass key light was blinking though.

If you want to bypass the vats module completely see his post I made in the pass key/vats thread:

http://www.impalassforum.com/vBulletin/11949745-post210.html

It was a bit of an after thought so that's the best how to I could make.

IDK what kind of module you got off ebay. Do you have a link? Seems most of them are just the resistor trick...it's not a vats bypass it's just a key bypass. The vats module still controls whether or not the car will start...all you're doing is making it think the key is inserted. Apparently the modules like to fail as I found out recently.

NSS could be the culprit as well and so could the ignition switch or the wires leading to it. Apparently those are also a common point of failure. I would think more common than NSS.
This is the one I used

Vehicle Anti Theft System Vats Bypass Keycode 2 | eBay

I just saw this one, is it the same thing just more money?

Fortin - PASSLOCK-SL2-V2 - GM Passlock And VATS Transponder Key Bypass Module
 

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You can't just bypass the VATS in the ECM. All you can do is disable the fuel cutoff.

The first link you posted is just the key bypass...this rules out a bad key in your case. The second one I'm not sure what it does. That's a lot of wires to splice though.

It says on the manufacturer website:

***** A FULLY functioning Passlock system and Working Key which is able to START the Vehicles at all times is required. FOR REMOTE STARTER USE ONLY.*****.
You don't have a fully functioning system. It doesn't say exactly what it does though. The wording makes it sound like it's just a key bypass but it's got too many wires for that lol

There's only one kit I know that completely bypasses the VATS module and that's almost $300 and you have to get it professionally installed.

If it is your VATS module then your options are to perform the bypass like I did (requires VATS fuel cutoff disabled in ECM). It's only one wire...or try your luck with the fortin thing which is 6 wires.
 

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Discussion Starter #12
You can't just bypass the VATS in the ECM. All you can do is disable the fuel cutoff.

The first link you posted is just the key bypass...this rules out a bad key in your case. The second one I'm not sure what it does. That's a lot of wires to splice though.

It says on the manufacturer website:



You don't have a fully functioning system. It doesn't say exactly what it does though. The wording makes it sound like it's just a key bypass but it's got too many wires for that lol

There's only one kit I know that completely bypasses the VATS module and that's almost $300 and you have to get it professionally installed.

If it is your VATS module then your options are to perform the bypass like I did (requires VATS fuel cutoff disabled in ECM). It's only one wire...or try your luck with the fortin thing which is 6 wires.
I'll have to ask around, I'm sure I have to know someone locally with the means to modify the tune and turn off the vats fuel cutoff.
 

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Could it have anything to do with the neutral safety switch? My column is old and the shifter does have some play to it, sometimes if I jiggle it around it will start
Yes it could easily be something like neutral safety switch.You're original post still leads me to beleive it may not be a VATS issue.

Try this Phil, turn and hold the key to start position with your left hand,then slowly move the column shifter around down from park. do this in neutral too. See if it starts.
 

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Discussion Starter #14
Yes it could easily be something like neutral safety switch.You're original post still leads me to beleive it may not be a VATS issue.

Try this Phil, turn and hold the key to start position with your left hand,then slowly move the column shifter around down from park. do this in neutral too. See if it starts.
I will try this tomorrow when I got to work (pizza delivery) it seems like I am usually good for the first bit of my shift but the longer I'm on the road the more trouble it gives me
 

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Discussion Starter #16
Yes it could easily be something like neutral safety switch.You're original post still leads me to beleive it may not be a VATS issue.

Try this Phil, turn and hold the key to start position with your left hand,then slowly move the column shifter around down from park. do this in neutral too. See if it starts.
That was a no go but so far tonight I have been having good luck by turning key to on position, waiting for pass key fault light to go out then wait an additional 5-10 seconds before attempting to crank
 

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Ok so since you already have the key bypass/resistor mod done, there is little to no chance that the VATS module is not receiving the proper resistance.

Have to checked the bypass resistor with a voltmeter to make sure it's still within spec? Compare it to your key resistance and compare to this chart:



If it's within spec then it really limits you to 2 or three things.

1) the connections for the ignition switch behind the key cylinder are broken. Seems to be a common issue as the wires are pretty flimsy, but this would produce a no start at all. Waiting 5 seconds wouldn't make a difference if the physical connection was broken. Also, moving the shifter or banging on the column might temporarily make a connection and allow the car to start. According to you, this is not the case.

2) The NSS is bad. I don't know how common of an issue that is but I would say pretty rare. And as you said it doesn't make and difference if you try and start in neutral, etc. It could be bad. Save for getting under there with a power probe or a volt meter and checking it out all you can do is guess. Or replace it.

3) The vats module is indeed bad. The way the module works is it reads the resistance from the key it's been programmed to. The bypass you have mimics the key. If the resistance is within the range on the chart, then the module provides ground to the starter relay and will allow the car to crank and start. If for any reason the VATS module has failed, or is failing, it will cause a no crank situation. In my particular case, the pass key light was blinking which means the module was getting no signal at all from the key, which was not possible so it was a failure of the module. However, based on everything I've read, that is not the only way it fails. Seems like based on the pass key thread you are in one of the stages of failure. Intermittent. Sooner or later, if it is the module, it will stop working all together.
 

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Discussion Starter #18
Ok so since you already have the key bypass/resistor mod done, there is little to no chance that the VATS module is not receiving the proper resistance.

Have to checked the bypass resistor with a voltmeter to make sure it's still within spec? Compare it to your key resistance and compare to this chart:



If it's within spec then it really limits you to 2 or three things.

1) the connections for the ignition switch behind the key cylinder are broken. Seems to be a common issue as the wires are pretty flimsy, but this would produce a no start at all. Waiting 5 seconds wouldn't make a difference if the physical connection was broken. Also, moving the shifter or banging on the column might temporarily make a connection and allow the car to start. According to you, this is not the case.

2) The NSS is bad. I don't know how common of an issue that is but I would say pretty rare. And as you said it doesn't make and difference if you try and start in neutral, etc. It could be bad. Save for getting under there with a power probe or a volt meter and checking it out all you can do is guess. Or replace it.

3) The vats module is indeed bad. The way the module works is it reads the resistance from the key it's been programmed to. The bypass you have mimics the key. If the resistance is within the range on the chart, then the module provides ground to the starter relay and will allow the car to crank and start. If for any reason the VATS module has failed, or is failing, it will cause a no crank situation. In my particular case, the pass key light was blinking which means the module was getting no signal at all from the key, which was not possible so it was a failure of the module. However, based on everything I've read, that is not the only way it fails. Seems like based on the pass key thread you are in one of the stages of failure. Intermittent. Sooner or later, if it is the module, it will stop working all together.
How do I check the resistance of the bypass? Its a sealed unit that plugs into the stock harness
 

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Good thoughts on this TGO. Agree the bypass mod resistor could be failing that's where I'd test first.Easy check as you describe above.

Good luck with it Phil.Let us know your ohm reading.

Jim
 
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