How to Bypass your VATS

**0rion** · 04-19-2011, 12:42 PM

Originally Posted by paulnei

Hello, Im new here, but as I am having some problems with dam VAT module, maybe you guys can help me.

My 98 Camaro is staying in the Garage all the winter, so as I tried to start it in this spring It did not start at all, the Security light was permanently on too.

I mesured the resistance of my key it was 4.750, bought resistor 4,7 one, cut the 2 white cables installed resistor (it is actually 4.64-4.65) as I found on http://www.thirdgen.org/vats_passkey_system
the reading can be between 4.560-4.960 so it should be fine?

Ok after that it started, I tried multiple times no problems at all. Then after few days I wanted to move my car and it wont start again, security light went off like it should, but the car still not starting, had engine light on all the time....

10 minutes later tried again and it was starting as it should...no security lights no engine light on...

Can it be a problem with resistor, should I buy gold one...? Or may it be fucked up VAT module??

the thing is if that resistor fails the security light will come on. When you say it wouldn't start (the second time) what was the car doing?
The goal for bypassing the vats is to get it as near the median of your range as possible. I would also strongly suggest using gold banded resistors.
It kinda sounds to me like this one isn't related to your vats due to the lack of the security light. Explain first what the car did when you tried to start it...nothing at all or did it turn over and just not start?

**5abivt** · 06-11-2011, 06:31 AM

I feel like for the firs time I had a problem that was the same as someone else. Thanks to the sticky I defeated my vats and my car started all in a matter of a few hours thanks to forum members help and linking me this sticky.

My key was 9.46 and 9.53

My first try was 2 4.7 1% resistors for 9.4k and the car fired right up. Such an easy fix to a potentially frustrating problem!

**KMdef9** · 06-11-2011, 07:09 AM

Originally Posted by 5abivt

I feel like for the firs time I had a problem that was the same as someone else. Thanks to the sticky I defeated my vats and my car started all in a matter of a few hours thanks to forum members help and linking me this sticky.

My key was 9.46 and 9.53

My first try was 2 4.7 1% resistors for 9.4k and the car fired right up. Such an easy fix to a potentially frustrating problem!

Glad it was a easy fix!

**silverWS6** · 09-06-2011, 09:28 PM

Well my VATS is giving me crap... again! A few weeks ago, when I thought I had already fixed the problem, I measured my key and it gave me 3.7x so I went out to radioshack and bought a 2.2 and a 1.5 and also bought a 3.9 (I measured the 3.9 one at Radioshack and it gave me a 3.7x reading so I figured that would work perfect). When I got home the damn light was off and it fired right up, so I decided to just go ahead and install the 3.9 resistor anyways. So I did that and the car had no issues after that, till today! It did the same thing again. So I pulled out the 3.9 one and put in the 1.5 and the 2.2 and still got a no go, I flipped them around and tried every combination possible and it wont start. My security light doesn't stay continuously on like before but sometimes it does, instead it'll stay on for a while and then turns off but when I try to turn it on again it'll just flash after I turn the key to the run position.

Now here is the catch, I don't have a spare key so I'm only going on the reading from my only key. Could it be that my key is bad instead and I actually got a wrong reading from my key? When the purple and white cables are disconnected from the pair of white cables does the Security light come right on? Because mine doesn't.

Also, when the VATS is bypassed does this fix any problems with the key cylinder having to be replaced? I was told from the gm tech that it might be my key cylinder when I called to get the price on a new key. I don't know if I should really believe him or if he just wants to get a job in.

Also I should probably mention that this started happening when I was constantly switching the car battery from my 02 to my 98. I sold the 98 with that battery so my 02 has been sitting without a battery for about 3 weeks now. Last Saturday I started it and moved it with the battery from my truck (02 Avalanche) and it did fine but today when I tried to return her to her position it started doing the problem again. Yes, I will buy her a battery all for herself no later than this week.

**Cutlass** · 09-07-2011, 04:39 PM

The key that is closest to the resistance you measured is #10. And it looks like its probably dead on. With VATS bypass with a resistor, the ignition cylinder is out of the circuit and can't be the problem.

**0rion** · 09-07-2011, 04:47 PM

Originally Posted by silverWS.6

Well my VATS is giving me crap... again! A few weeks ago, when I thought I had already fixed the problem, I measured my key and it gave me 3.7x so I went out to radioshack and bought a 2.2 and a 1.5 and also bought a 3.9 (I measured the 3.9 one at Radioshack and it gave me a 3.7x reading so I figured that would work perfect). When I got home the damn light was off and it fired right up, so I decided to just go ahead and install the 3.9 resistor anyways. So I did that and the car had no issues after that, till today! It did the same thing again. So I pulled out the 3.9 one and put in the 1.5 and the 2.2 and still got a no go, I flipped them around and tried every combination possible and it wont start. My security light doesn't stay continuously on like before but sometimes it does, instead it'll stay on for a while and then turns off but when I try to turn it on again it'll just flash after I turn the key to the run position.

Now here is the catch, I don't have a spare key so I'm only going on the reading from my only key. Could it be that my key is bad instead and I actually got a wrong reading from my key? When the purple and white cables are disconnected from the pair of white cables does the Security light come right on? Because mine doesn't.

Also, when the VATS is bypassed does this fix any problems with the key cylinder having to be replaced? I was told from the gm tech that it might be my key cylinder when I called to get the price on a new key. I don't know if I should really believe him or if he just wants to get a job in.

Also I should probably mention that this started happening when I was constantly switching the car battery from my 02 to my 98. I sold the 98 with that battery so my 02 has been sitting without a battery for about 3 weeks now. Last Saturday I started it and moved it with the battery from my truck (02 Avalanche) and it did fine but today when I tried to return her to her position it started doing the problem again. Yes, I will buy her a battery all for herself no later than this week.

almost everytime someone does a vats bypass and it doesn't work right it's because they have something wrong. Go over everything with a fine toothed comb and verify you're using gold band resistors and they're secured well. Get those ohms as close to 3740 as possible.

**silverWS6** · 09-07-2011, 05:57 PM

Originally Posted by Cutlass

The key that is closest to the resistance you measured is #10. And it looks like its probably dead on. With VATS bypass with a resistor, the ignition cylinder is out of the circuit and can't be the problem.

Well that's a relief on the ignition cylinder!

Originally Posted by 0rion

almost everytime someone does a vats bypass and it doesn't work right it's because they have something wrong. Go over everything with a fine toothed comb and verify you're using gold band resistors and they're secured well. Get those ohms as close to 3740 as possible.

Yeah, I think that's the problem! I will try again this weekend when I buy a new battery and try once again. I will try to solder them if I can find a friend that has one.
These are gold bands right?

**silverWS6** · 09-22-2011, 07:11 PM

Quick question! White wires go to ignition cylinder and the colored wires go to the pcm? If so, can I just cut the white wires and add the resistor there with some butt connectors for a secure fit instead of just electrical tape? Then plug in the connector of the white wires back on?

once again...

**0rion** · 09-22-2011, 09:16 PM

that's how I did it except I soldered the resistors to the white wires. I cut those wires about an inch or so on the column side of the plug, soldered the resistors end to end between them, and pluged it back in. That's another thing...if you have more than 1 resistor you have to do them end to end in a series and not all twisted together in parallel. Current is like water.....it'll take the path of least resistance. You probably already knew that but thought I'd throw it in there just in case.

**silverWS6** · 09-22-2011, 10:20 PM

Originally Posted by 0rion

that's how I did it except I soldered the resistors to the white wires. I cut those wires about an inch or so on the column side of the plug, soldered the resistors end to end between them, and pluged it back in. That's another thing...if you have more than 1 resistor you have to do them end to end in a series and not all twisted together in parallel. Current is like water.....it'll take the path of least resistance. You probably already knew that but thought I'd throw it in there just in case.

Yeah I think I'm going to do it that way instead to get a more secure hold on it so it wont slip out again. Now I am going to use the 3.9 resistor as it gave me a reading of 3.81. So according to the chart up there my key is #10 so if I put the 3.8 in then I'll be fine within the lines of maximum and minimum resistance needed. Correct?

**silverWS6** · 09-23-2011, 02:22 PM

Wtf am I doing wrong! I tried it today again, I did exactly what I said up top. I put in the 3.9 resistor that gave a actual 3.81 and once I put it up to the white wires with butt connectors it gave me a 3.83, in between the maximun and minumum right? So it fired right up and all was good. Then I head to go put some gas and while I was pumping gas the light came back but after 2 times of trying and it resting about 5 seconds it turned off and started up. Ill do a mspaint drawing later of how I put the resistor in and wired it up. This shit is getting annoying.

I've cranked about 5 times and it that just once and it was about the 3rd time, the pcm doesn't always check that or what?

**Billk** · 09-23-2011, 02:24 PM

Hello, new here. I have a 2000 camaro v6 automatic. When I first got the car it did this no turning over and security light on. It quit doing that for like a year but now its doing it again. I checked the resistance of the key and at the plug with the orange wires. There is about the same resistance at the plug as at the key. Does that mean I probably need a new BCM? Thanks.

**Cutlass** · 09-23-2011, 02:30 PM

Originally Posted by silverWS.6

Wtf am I doing wrong! I tried it today again, I did exactly what I said up top. I put in the 3.9 resistor that gave a actual 3.81 and once I put it up to the white wires with butt connectors it gave me a 3.83, in between the maximun and minumum right? So it fired right up and all was good. Then I head to go put some gas and while I was pumping gas the light came back but after 2 times of trying and it resting about 5 seconds it turned off and started up. Ill do a mspaint drawing later of how I put the resistor in and wired it up. This shit is getting annoying.

I've cranked about 5 times and it that just once and it was about the 3rd time, the pcm doesn't always check that or what?

I'm thinking you did the bypass correctly, but there can be/might be other issues with the VATs system causing your problems.

**Cutlass** · 09-23-2011, 02:32 PM

Originally Posted by Billk

Hello, new here. I have a 2000 camaro v6 automatic. When I first got the car it did this no turning over and security light on. It quit doing that for like a year but now its doing it again. I checked the resistance of the key and at the plug with the orange wires. There is about the same resistance at the plug as at the key. Does that mean I probably need a new BCM? Thanks.

Did you check the resistance as you turned the ignition cylinder. the wires might go open as you turn the cylinder.

**Billk** · 09-24-2011, 12:44 PM

Originally Posted by Cutlass

Did you check the resistance as you turned the ignition cylinder. the wires might go open as you turn the cylinder.

I checked today. I didnt notice the resistance dropping at all as I turned it. Think it would be worth it to replace the key lock cylinder anyway or any other ideas? It did start about 3 times when I tried the resistor trick but I think that without the resistor even in, just the wires unplugged from each other. Thanks.

**Cutlass** · 09-25-2011, 05:06 PM

Originally Posted by Billk

I checked today. I didnt notice the resistance dropping at all as I turned it. Think it would be worth it to replace the key lock cylinder anyway or any other ideas? It did start about 3 times when I tried the resistor trick but I think that without the resistor even in, just the wires unplugged from each other. Thanks.

Hard to say. When everything tests ok, its trickier to diagnose

**0rion** · 09-26-2011, 09:23 PM

Originally Posted by silverWS.6

Wtf am I doing wrong! I tried it today again, I did exactly what I said up top. I put in the 3.9 resistor that gave a actual 3.81 and once I put it up to the white wires with butt connectors it gave me a 3.83, in between the maximun and minumum right? So it fired right up and all was good. Then I head to go put some gas and while I was pumping gas the light came back but after 2 times of trying and it resting about 5 seconds it turned off and started up. Ill do a mspaint drawing later of how I put the resistor in and wired it up. This shit is getting annoying.

I've cranked about 5 times and it that just once and it was about the 3rd time, the pcm doesn't always check that or what?

why are you shooting so high on the scale? You really want it to be as close to 3740 as possible. All resistors will have variation....you want to make sure you're not getting out of tolerance with it so you shoot as close to the median as possible. You may end up having an issue other than the key cylinder but before you go down that road get those ohms dead on the median and solder them together. 99 out of 100 vats issues are in the key cylinder I bet. Make sure you're doing it correctly the first time though. Gold band resistors like you have, measure your key pellets resistance to make sure you're using the right pellet code, get those ohms as close to the median as possible, and solder everything.

**pk222** · 09-26-2011, 09:29 PM

Not to jump on anyones thread but friends going through this to in his 97. Wouldn't it be way easier to use a pljx module?

**2001SSVert** · 01-07-2012, 10:42 PM

It's funny how when VATS starts to go... it goes really QUICK.

I've had my 2001 SS Convertible for 7 years now, never a problem starting, but suddenly in the last few weeks it went from an occasional 'SECURITY' lamp and then start...to waiting for one 3 minute cycle for the lamp to go out and try again and start... to waiting TWO 3 minute cycles and then start... to changing the tilt up all the way and turning the steering to the right and swearing loudly then start.

Went to what was once RadioShack up here (now called the Source), bought a resistor value pack (5% 1/4W), a multimeter, already had the soldering gun & solder (from fixing the factory flaw solder cracked connections on the BCM for the intermittent windows/convertible top problem - has worked perfectly since)

Tested my keys... Original Key was 4.72K Ohm, Newer Spare was 4.76K - Corresponds to pellet 11 that the chart says 4.75K is nominal.

Soldered a 4.7K & 47K resistor together in series to the ends of the cut white wires with orange shrink connector, wrapped in electrical tape... Completed Bypass tested in the multimeter to be exactly 4.75K

Plugged back into the connector, turned the key... Started up good as new, NO 'SECURITY' Light! Imagine...Actually starting your car the moment you actually need to GO! Like NOW!

VERY HAPPY! Thanks LS1.com

**2001SSVert** · 01-08-2012, 12:10 PM

THANK YOU! So HAPPY!

EASY FIX - My SS is pellet 11 - 4.75K / Keys tested @ 4.72 & 4.76

Cut the orange shrink/white wire side of connector... Soldered a 4.7K & 47K resistor together in series to the connector, wrapped in electrical tape... Final test was exactly 4.75K

Plugged bypass connector back in...Car starts instantly everytime, no more false 'SECURITY' lamp wasting my life in 3 minute cycles.

Thanks LS1.com!