Passlock II SECURITY light and truck won't start!

[ScottyBoy]

If you already have a bypass for your remote start, does your remote start ever give you problems starting like it does with the key?
Also, the bypass module does not permantly bypass the passlock system. There is a trigger wire on it that is energized by the remote start module. So only when the remote start is activated is the bypass active and working. If you wanted to have your bypass modue permanantly bypass the passlock, you could just ground that trigger wire.

Just found this site. Perhaps a way to bypass the Passlock without purchasing an aftermarket kit/alarm add-on. Seems like it would apply to all vehicles, but perhaps those of you out there with more experience than I can confirm this.

http://www.bergerweb.net/PasslockFix/index.shtml

Also, the way its permanantly bypassed in that link is actually a very reliable way of bypassing it. I used to be an alarm/remote start installer and back before the bypass modules even hit the market thats how we used to bypass the passlock when installing a remote start. The only difference was that we wired it to a relay so that it was only active when triggered by the remote start. The ONLY time I have heard of any problems with the resistor bypass is in severely cold climates up north where temps dip below 0 degreez for extended periods.

 

[tlamot01]

Scott, when the truck displays symptoms of Passlock failure, the remote starter will not work either. So you're telling me that the bypass module is passive and only activates when it is triggered by the remote starter; perhaps through a relay triggering the bypass's resistance value through the yellow wire and back into the ignition switch?

Then this leads me to believe there is still some common wiring or connectors between the two units that may be faulty. I recall cutting the yellow wire and attaching both ends of it to leads from the bypass module. I don't think the other two wires were cut, but maybe one of them (middle orange/black wire) was tapped into...

Perhaps the BCM is the issue then, since both systems now feed into it?

PS. Day three and the SECURITY light is still on, but truck continues to start...

 

[ScottyBoy]

Scott, when the truck displays symptoms of Passlock failure, the remote starter will not work either. So you're telling me that the bypass module is passive and only activates when it is triggered by the remote starter; perhaps through a relay triggering the bypass's resistance value through the yellow wire and back into the ignition switch?

Then this leads me to believe there is still some common wiring or connectors between the two units that may be faulty. I recall cutting the yellow wire and attaching both ends of it to leads from the bypass module. I don't think the other two wires were cut, but maybe one of them (middle orange/black wire) was tapped into...

Perhaps the BCM is the issue then, since both systems now feed into it?

PS. Day three and the SECURITY light is still on, but truck continues to start...

You are describing a DEI 555L module. Thats EXACTLY how it wires in. You cut the yellow wire and each end connects to the 555L module. See if you can find the module and confirm that it is indeed a 555L. If so, you should be able to ground the blue/black wire and have it be permanantly bypassed. The blue/black wire should be connected to a wire on your remote starter. Try cutting it off of the remote starter and permanantly attaching it to ground. But make sure its not in anti theft mode when you do that or it will not work.
Also, that may put a drain on your battery . If it does, you may want to wire it up to a switch.

 

[ScottyBoy]

You get this figured out yet?

 

[992dr]

You get this figured out yet?

I'm also curious to know.

 

[tlamot01]

Honestly guys, I had to get the truck in for smog/safety inspection so I could get it registered here in Missouri. Once the thing started working again (after the 30 minute passlock relearn procedure), I put the dash and column back together. So far, the truck continues to start but the security light is still illuminated. I read somewhere that the fault code remains for 100 ignition cycles. I'm not about to start my truck 100 times just to test that...
Now that I'm registered, I might re-visit this problem this weekend (with pics). Thanks fellas.

 

[992dr]

It sounds about right. At first it would happen every other month.
Good luck, check back in and let us know.

 

[letsbangout]

This all sounds like foolishness to me. I, too, have persistent Passlock problems. I'm prepared to permanently disable Passlock by buying HPTuners' software and programming the PCM not to act on the injector enable signal (yes, you can do that. Why more people on this board don't talk about it, I don't know.) Or I might be able to disable it by generating the TDM's "enable signal" and feeding it straight to the PCM. That seems to be my problem (like countless others) - that the TDM/BCM are inherently broken by design, and it doesn't matter what resistance you feed it, it's still broken. My research has revealed two candidates to fix this on a permanent basis:

DIY: http://home.hiwaay.net/~davida1/passkey.htm

Commercial: http://www.bakerelectronix.com/products_vats/

The only thing puzzling to me at this point is which signal line do I use? I can't identify it on the PCM, per this diagram: http://www.tahoeyukonforum.com/forum/showthread.php?t=28479 and on the BCM wiring diagram as well.

Does anyone have experience with these or similar bypass mechanisms that also bypass the TDM/BCM? And which signal line to feed the PCM with on a 99 Yukon?

 

[letsbangout]

This all sounds like foolishness to me. I, too, have persistent Passlock problems. I'm prepared to permanently disable Passlock by buying HPTuners' software and programming the PCM not to act on the injector enable signal (yes, you can do that. Why more people on this board don't talk about it, I don't know.) Or I might be able to disable it by generating the BCM's "enable signal" and feeding it straight to the PCM. That seems to be my problem (like countless others) - that the TDM/BCM are inherently broken by design, and it doesn't matter what resistance you feed it, it's still broken. My research has revealed two candidates to fix this on a permanent basis:

DIY: http://home.hiwaay.net/~davida1/passkey.htm

Commercial: http://www.bakerelectronix.com/products_vats/

The only thing puzzling to me at this point is which signal line do I use? I can't identify it on the PCM, per this diagram: http://www.tahoeyukonforum.com/forum/showthread.php?t=28479 and on the BCM wiring diagram as well.

Does anyone have experience with these or similar bypass mechanisms that also bypass the TDM/BCM? And which signal line to feed the PCM with on a 99 Yukon?

So in the absence of any relevant replies, I decided to buy the e-book from http://newrockies.com/the-problem-and-the-solution/diy/ to build a VATS/Passkey bypass mechanism. This is the same circuit I referenced above. The reason I bought it is because 1) I figured it would include instructions on how to interface it to the PCM (which it does), and 2) I didn't realize that module is only for VATS/Passkey systems, in other words, cars with stand-alone Theft Deterrent Modules, of which 97+ Tahoes/Yukons are not (because the TDM is integrated into the steering control module). It was probably not money wasted, because I'm now of the opinion that the only real way to deal with this, besides buying one of NewRockies' "Pro" modules (I'm guessing it's something that taps onto the serial interface of the TDM and tells the PCM it's ok to start the truck), is to break down and get a tune with HPTuners of EFIlive software that instructs the PCM not to look at the TDM's status.

Before I do that, though, I'm going to pull out my Steering Control Module (because my power steering is acting up - it seems to be commanding max pressure from the pump at all times, even with the steering position sensor disconnected - not sure if that's normal behavior). Since I already have the yellow Passlock sensor wire clipped, I may solder in a resistor directly to the SCM. So unless the SCM is broken (which it could be, given what I said above), it should work for a while. But I swear I'm going to start socking away money to buy HPTuners Pro package for $650 and turn this big negative into a positive.

 

[slipping]

Awesome research. I'm gonna try and get the items necessary to build me one of these deals. For both the Tahoe and my camaro. Right now I have a wire running from the relay under the Hood to a spot next to ground so when I turn key and touch it starts. Ghettofabulous

___________________________
99 4 door Hoe lifted
04 Hoe stock
94 z28 lowered, being referbished