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Discussion Starter · #1 ·
Ive recently become victim of the passlock system on my 99 gmc suburban 1500 4x4.
I want to bypass this security system all together. After some research and studying the wiring diagrams it seems plausible that you could cut the fuel pump relay wire and run it directly into the "hot when on or start" part of the ignition. Just curious if anyone else has done this?
 

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Discussion Starter · #2 ·
Or is it the fuel injectors this security system disables?
 

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taggat......the Passlock System, means Your Vehicle is Equipped with the Passlock Theft-Deterrent System,

Passlock is a Passive Theft-Deterrent System. Passlock Enables Fuel if the Ignition Lock Cylinder is Turned with a Valid Key. If a Correct Key is Not Used or the Ignition Lock Cylinder is Tampered with......The Fuel is Disabled.
 

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Discussion Starter · #4 ·
The fuel is disabled... is it the fuel pump relay or the fuel injectors?

Its been running fine until the other day when the security light came on flashing. Attempted the reset sequence a few times and nothing. Replaced the security light fuse, checked the other fuses as well. Ive looked into the proper repair procedure to replace the ignition cylinder that has the passlock sensor in it. If that doesnt work start replacing all of the other crap that makes up this system until it works. I simply want to drive my burb not throw money at it. I only received one key when I bought it. It is the early version with no sensor in the key stock.

I dont care about the security system and I dont want it to fail again at any time.

Has anyone ever put a performance vcm on their suburban?

Vcm swap to the 0411 off of earlier vans and such?

Im curious if the passlock system couldnt just be turned off in the vcm via a tuner, "you know, a really smart laptop mechanic".
 

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Fuel pump, injectors, igntion, starter, radio are all disabled withou a valid key.

If you want to actually disable PassKey, you need to program the computer modules to not use it. It can be disabled (is done all the time when swapping newer engines in older cars), but you shouldn't go around trying to cut wiring and bypass things with wires. You'll only make things worse, and possibly even cause a fire, if you go that route.
 

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Discussion Starter · #6 · (Edited)
With my version of the passlock system it still allows the vehicle to run for 3 seconds before cutting the fuel.
I shimmed the loose 3 wire connection at the key and got the reset sequence to work last night but.... Im still looking for the ultimate bypass.
 

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Discussion Starter · #7 ·
Finally found someone to take care of it.

Mike Norris Motorsports
3828 Clarks Creek Road
Plainfield, IN 46168
407-616-2518

The quote 250 bucks to reprogram the vcm so that the VATSystem is "off"!

Im happy, cheers to you all.
 

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Finally found someone to take care of it.

Mike Norris Motorsports
3828 Clarks Creek Road
Plainfield, IN 46168
407-616-2518

The quote 250 bucks to reprogram the vcm so that the VATSystem is "off"!

Im happy, cheers to you all.
For that amount of money you might as well call blackbear and have them do a custom tune, they can shut off the security while they do it. Then you get a performance upgrade, your security issue fixed, and save $10
 

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$250 is ripoff to just do the disabling, when I disabled mine I just used the $20 fix on eBay and it's worked beautifully for the last 3 years. Google eBay vats bypass, it's a little micro chip with three wires blue, black and red. Red goes to pink 12v ignition wire, black to ground, and blue to vats input wire.
 

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Discussion Starter · #12 ·
Checked out Blackbear, I could be wrong but it looks like its 330 bucks.
 

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You keep saying you don't have a chip in your key. Did you have a new key cut to replace the original factory key or something, without having the chip in the key?
 

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You don't need to buy anything other than a 4-pack of resistors at Radio Shack $1.50, and do some minor soldering.

I think I've figured out the main cause of the Passlock 2 system's failures. It was poorly designed, and wears out. Some a lot earlier –too early - than others, but wearing out is inevitable.

Basically, the Passlock 2 security system disables the fuel supply if the computer doesn't recognize the keyed ignition lock cylinder is turning legitimately. The turning cylinder has 2 small magnets and as it turns past a coil - more or less - creates a hall effect. The computer sends a signal to the key switch and when key cylinder is turned with correct key, the returning signal or "code" runs through to the Passlock 2 module that tells the car's computer that's all's well and everything works fine. Unfortunately, GM owners have had to deal with intermittent immobilization, no-start conditions, and even total failures.

A typical incident would be – you go out to your car, put in the key, turn it over, it cranks and starts and within 2-3 seconds, stops running. You try to crank it again, but it won’t start up and the SECURITY light is blinking.
The reset process – if you’re lucky enough to know it - is to turn on the key, and wait until the blinking security light goes steady (usually 10 minutes), then turn off the ignition, wait 10 seconds and then it will start back up and off you go. This can happen at the worst times, and it can be a month or so between events. Or it happens every day. When you perform a reset, the system really isn’t resetting, it’s “relearning”. The value or code returning to the module has changed somehow. The 10-minute wait is for the computer to learn to accept the new value or relearn the “code”, which it does. The reason behind these failures is simple. The "code" sent to the module that tells the car's computer has changed somehow, and therefore the module doesn’t recognize the new “code” and tells the computer to turn OFF the fuel. So what causes the "code" to change?

-Bad connections. There have been a few on-line videos that show loose connections, and bad or dirty contacts. Cleaning and better securing has helped lots of owners out there. Basically the bad connections changed the "code" out of its tolerance. It’s all very sensitive. But the owners plagued by these failures overwhelmingly have a bit more going on. All the cleaning won't help.

-Bad components.
Basically, the internals of the Passlock key component wear out. The lockset, magnets, the connections, the resistors etc. all wear out. Your choice is to replace it all or BYPASS the system for good, which means your car can be hot-wired and stolen. If you replace the system components, I recommend replacing the whole enchilada, key cylinder included. Cost at the dealership is about $1000+. If you choose to BYPASS the system, the process involves locating and cutting into 2-wires between the module and key switch and soldering a resistor (5-10k ohms) between the two wires. Go through “relearn” process and no more issue. Cost is about $2 and a ½ day.
 

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or you could get a reman module for 150.00 with lifetime warranty and be done with bypassing anything or cutting wires
 
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