How do thieves circumvent the passlock theft deterrent?

[MassHoe04]

I don't think I will do this anytime soon, but I like the idea of a simple push button or toggle switch that needs to be pressed or on when the key is turned to start position.

Thieves will probably be looking for "hidden" kill switch devices and know how to bypass them. Most thieves aren't geniuses, so hiding a switch in plain sight might be the best option.

I would lean towards installation of a rocker switch that is labeled "Zombie Killer", "Ejection Seat", "Light Bar 3" or something that looks like a switch that might serve an everyday purpose. Your everyday car thief would probably not suspect a device that is right there in front of them that looks like it does something legitimate.

 

[DougAMiller]

Thanks for this information. This confirms what I was thinking and lines up with what is seen on the video I watched of the truck being stolen. The guy appears to push something into the driver's door, once inside the truck, it is started in less than 30 seconds and is gone. I knew about the factory alarm being bypassed by punching the lock, so the logical choice would be to install a standalone alarm system with a starter disable to not make it so easy. And maybe something else that would be a deterrent for someone looking for a fast easy steal. I suppose if you could disconnect the factory alarm from the door lock so it isn't easily defeated could also help. I realize someone determined to steal something will do whatever it takes, but considering how easy it easy to steal this era truck/SUV it's not surprising it happens so often.

Brian

Disconnecting the factory alarm from the door isn't so simple. It's all managed in the BCM and you would lose other functionality by unplugging the switch in the door latch. For most thieves, just interrupting their routine and making it take longer will often make them move on to the next car. Something as simple as a sticker or flashing LED indicating an aftermarket alarm, even if there really isn't one installed, can make them skip you for someone else that is vulnerable to their practiced technique. If they're really determined and can take the time, they will get it, the hope is that you can slow things down enough to get them to go elsewhere.

 

[rockola1971]

Easiest way to prevent your ride from being stolen is install the K.I.T.T. factory option. All us old guys know what that is.

Reminds me of the mid 80's GM "chip" on the key. Which was just a resistor. There was a reader in the ignition lock cylinder that read the resistance of the resistor (chip) on your key and that resistance was fed into the ECM for a yay or nay. What was funny was there were only around 8 different values or so for my 1985 Corvette. To install a aftermarket alarm system on these generation cars you would get this "bypass module" which was really just a variable resistor set in a box with in and out wires. Set the box to your value on your key as measured by an ohmeter and install in series with the reader and your factory alarm system was bypassed all the time allowing for a aftermarket alarm system to be wired in and it had a relay that was wired in series with the large gauge pink wire (on GM) which killed ignition voltage to the engine when interrupted by alarm system relay.

 

[briand069]

Disconnecting the factory alarm from the door isn't so simple. It's all managed in the BCM and you would lose other functionality by unplugging the switch in the door latch. For most thieves, just interrupting their routine and making it take longer will often make them move on to the next car. Something as simple as a sticker or flashing LED indicating an aftermarket alarm, even if there really isn't one installed, can make them skip you for someone else that is vulnerable to their practiced technique. If they're really determined and can take the time, they will get it, the hope is that you can slow things down enough to get them to go elsewhere

I have an update to this. You can in fact disable the key lock switch so if the door lock is punched and opened, it will alarm. I read through the service manual on the operation of the system, then looked at the schematic. The door lock has its own switch/circuit, circled in the diagram. It's a 2 wire plug. The only functions it serves is to arm the alarm when you lock it with the key and disarm it when unlocking with the key. So, I simply unplugged it and tested it. With the alarm armed, unlocking the door with the key an opening it sets the alarm off. This is the same as breaking the window and unlocking the manual door lock. The only 2 downsides I see are, you set the alarm off when using the key top open and you can't arm the alarm with the key. I've only used my key to unlock my Suburban when the battery was dead. I also attached a picture of the plug from the driver's door on my Sierra. Its the top one on the lock mechanism and the release tab is right against the metal door. Both the driver and passenger door had green plugs as well. I think this at least makes the factory alarm a little useful. Stacked with other protection measures, like a kill switch it might prevent someone looking for an easy steal.

There may be a way to modify the switch so you can still arm the alarm, but I don't have a spare switch to mess with to try it. This is the text from the manual on the switch.


The only thing I don't know or know how to test it. If the alarm is going off and the person rips the column cover off and forces the ignition lock, will it stop alarming?

Anyways, hope this helps someone. I'll be doing the same on my Suburban tomorrow. Looking at the schematics, the rear passenger doors don't have the same switch, only the door ajar one. The rear tailgate and cargo doors also have a door lock switch. I may look into unhooking that one as well.

Brian

 

[DougAMiller]

I have an update to this. You can in fact disable the key lock switch so if the door lock is punched and opened, it will alarm. I read through the service manual on the operation of the system, then looked at the schematic. The door lock has its own switch/circuit, circled in the diagram. It's a 2 wire plug. The only functions it serves is to arm the alarm when you lock it with the key and disarm it when unlocking with the key. So, I simply unplugged it and tested it. With the alarm armed, unlocking the door with the key an opening it sets the alarm off. This is the same as breaking the window and unlocking the manual door lock. The only 2 downsides I see are, you set the alarm off when using the key top open and you can't arm the alarm with the key. I've only used my key to unlock my Suburban when the battery was dead. I also attached a picture of the plug from the driver's door on my Sierra. Its the top one on the lock mechanism and the release tab is right against the metal door. Both the driver and passenger door had green plugs as well. I think this at least makes the factory alarm a little useful. Stacked with other protection measures, like a kill switch it might prevent someone looking for an easy steal.

There may be a way to modify the switch so you can still arm the alarm, but I don't have a spare switch to mess with to try it. This is the text from the manual on the switch.


The only thing I don't know or know how to test it. If the alarm is going off and the person rips the column cover off and forces the ignition lock, will it stop alarming?

Anyways, hope this helps someone. I'll be doing the same on my Suburban tomorrow. Looking at the schematics, the rear passenger doors don't have the same switch, only the door ajar one. The rear tailgate and cargo doors also have a door lock switch. I may look into unhooking that one as well.

Brian

Well, it seems I stand corrected. I had to disassemble my driver door latch to clean the electrical contacts sometime back because the interior lights were starting to act up. I thought I remembered that switch having more than one function.

 

[malaka]

I have an update to this. You can in fact disable the key lock switch so if the door lock is punched and opened, it will alarm. I read through the service manual on the operation of the system, then looked at the schematic. The door lock has its own switch/circuit, circled in the diagram. It's a 2 wire plug. The only functions it serves is to arm the alarm when you lock it with the key and disarm it when unlocking with the key. So, I simply unplugged it and tested it. With the alarm armed, unlocking the door with the key an opening it sets the alarm off. This is the same as breaking the window and unlocking the manual door lock. The only 2 downsides I see are, you set the alarm off when using the key top open and you can't arm the alarm with the key. I've only used my key to unlock my Suburban when the battery was dead. I also attached a picture of the plug from the driver's door on my Sierra. Its the top one on the lock mechanism and the release tab is right against the metal door. Both the driver and passenger door had green plugs as well. I think this at least makes the factory alarm a little useful. Stacked with other protection measures, like a kill switch it might prevent someone looking for an easy steal.

There may be a way to modify the switch so you can still arm the alarm, but I don't have a spare switch to mess with to try it. This is the text from the manual on the switch.


The only thing I don't know or know how to test it. If the alarm is going off and the person rips the column cover off and forces the ignition lock, will it stop alarming?

Anyways, hope this helps someone. I'll be doing the same on my Suburban tomorrow. Looking at the schematics, the rear passenger doors don't have the same switch, only the door ajar one. The rear tailgate and cargo doors also have a door lock switch. I may look into unhooking that one as well.

Brian

Brian,

How has this worked out for you? Any issues?

 

[adriver]

They tried to steal mine this way a couple of years ago, so I can explain the procedure. First they punch the lock cylinder in the driver's door. The door handle and base are plastic and hitting the cylinder hard will break the plastic ears that hold the cylinder in. Then it is a simple matter of turning the entire lock cylinder to unlock the truck, which also turns off the factory alarm.

The ignition cylinder is forced by ripping away the column cover to expose the protruding end of the cylinder and using vise grip or channel lock pliers to force it to rotate. There is a steel pin that prevents this, but the cylinder housing is aluminum, so they are trying to break that. The Passlock is entirely contained in the ignition lock cylinder and housing, the key has nothing to do with it, so if you can turn the cylinder the Passlock system is happy and lets it start. Getting the locking pin housing to break is a 50/50 proposition and depends partly on how good of a grip they get with the pliers. In my case they twisted off the end of lock cylinder instead and couldn't get another good bite on it with the pliers, so they gave up at that point. Sometimes, instead of pliers, they drive a screwdriver into the ignition lock cylinder and try to force it by using some kind of lever to rotate the screwdriver, but again, sometimes the soft metal of the lock cylinder gives first.

There are products out there that try to interrupt this method, like the Club or Jimmi Jammers, but from my research I don't think any of them are more effective than a good aftermarket alarm or a hidden kill switch, as others have been suggesting. Back when mine was broken into I had modelled the door handle base in CAD and was planning to have it machined from aluminum or steel so that they couldn't punch out the door lock, but before I got finished with that project I got a new Escalade, so never did get any made.

This is why I get ......... I want to talk about how this is a COMPLETE lack of street smarts to post something like this. Isn't this about the same time when all the hyundai and kia thefts started too. I also don't think this is how, I think I know how, and I'm not going to say how.

Personally, the best way to prevent theft is to wire in a kill switch.
Disconnect your battery, pull up the fuse panel, and pull out either the: injection or fuel pump connector pin off the panel. Wire a switch in line, and feed it into the cab. Route your wire hidden and install whatever switch that can't be seen. You could wiire it flush to the kick panel, under the seat to where you can only feel for it, under the center console, under the dash, heck wire it up the a-pillar and replace a map light. You could even swap make it the onstar button. Could even do a small push button above the pedals that you step on, kinda like the old high beam truck switches. It could also be completely under the carpet lets say next to the seat, where it's completely hidden even if looking right at it, and won't get accidentally kicked, and can be engaged with, where your passenger wouldn't even notice. (I THINK IT'S BEST NOT SAY EXACTLY WHERE TO PUT IT). Wire it back up and connect it in. If you can find a hidden spot, you could even just splice it in in-line.

If you really want to be slick about it, you could even (go pull if you need to, and) use old wiring so it blends in on both sides of the firewall.

 

[RST Dana]

Insurance can replace most of your investment. It hardly ever covers the labor hours we spend on making these rigs “ours”. Unless you have a perimeter system to announce an invasion, your custom theft protection efforts are may only be giving you the feel good vibes. Bad guys need access to the inside, once inside, they either need to start and drive, or take out your goodies. No bueno. GPS tracking/Onstar and or perimeter defense protection would be Primo. Switches, sirens, etc may not be enough. Even if the perp rolls in with a ****** and grab rollback truck, you can still hope the efforts would deter the removal of it, or hope it could be tracked before more damage has happened.

I awoke this weekend from a dream I experienced where my RST have been on some one else’s wish list, except I had to learn about it when I discovered it missing. Man, I was happy when I realized I was still in my bed!!

 

[Doubeleive]

Insurance can replace most of your investment. It hardly ever covers the labor hours we spend on making these rigs “ours”. Unless you have a perimeter system to announce an invasion, your custom theft protection efforts are may only be giving you the feel good vibes. Bad guys need access to the inside, once inside, they either need to start and drive, or take out your goodies. No bueno. GPS tracking/Onstar and or perimeter defense protection would be Primo. Switches, sirens, etc may not be enough. Even if the perp rolls in with a ****** and grab rollback truck, you can still hope the efforts would deter the removal of it, or hope it could be tracked before more damage has happened.

I awoke this weekend from a dream I experienced where my RST have been on some one else’s wish list, except I had to learn about it when I discovered it missing. Man, I was happy when I realized I was still in my bed!!

around here they just break a window and climb in and do whatever they need to, no need to open a door and trigger the alarm. I have opted for a 3rd party solution to that and other possibilities.

 

[swathdiver]

I have opted for a 3rd party solution to that and other possibilities.