gm passlock ii bypass problem

Hi all,

I'm installing a remote start on a 2003 GMC Sierra. I am using a DEI 456GW passlock bypass module. I have connected the module as per the installation instructions and verified its communication with the car via the double lock after connecting it. The remote start is installed with tach programming procedure completed successfully.

The issue I am facing is the Passlock immobilizer is kicking in shortly after cranking. I have verified this is the case because the passlock light on the dash lights up when the remote start attempt is killed (car with a lock through it). I have checked that the disarm output is properly connected to the 456GW module. It pulses this wire before the remote start (as described in the remote starter manual). I have double checked this with a DVM.

I'm confused because I'm confident the 456GW is working correctly (power locks work) but the starter kill bypass isn't working. I can't find enough documentation on the 456GW, the paper it came with is pretty thin. I'm assuming the pulse on the disarm wire is correct.

I have also tried enabling securelock mode on the remote starter just in case it would help. The remote starter succesfully unlocks the doors tries to start and relocks the doors. But the start is still shut down by the Passlock system.

Any help would be greatly appreciated.

Scott

This is what I did with my PassLock II on my 0 Grand Am GT1... I started the car by key, and cut the Yellow wire in the 3 wire Passlock II harness... The "Security" Light comes on all the damn time, but I'm working on that... I think,  I'm just going to take out the bulb. Anyways, this is per a GM Buliten posted by GM.  The main trick is, to ONLY cut the wire while the car is running, AND must be started by KEY... Check this link for a pic of what the wires look like..... https://64.85.6.121/diagrams/Images.asp?ImageID=967&link=BULLDOG As a matter of fact, check out www.bulldogsecurity.com and click on Vehicle Wiring Diagrams, Select GMC, and then Sierria, Read through everything they have to say, and look at their pics.... I'm just offering you a way to check to see if it's your bypass module.  If you start the car by key, cut the yellow wire, shut off the car, then try to start if by key again, then by remote.... this should work... If not let me know and we'll try somthing else

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The Only Stupid Question, is the one Un-asked

i would never do the relay and resistor method. during the cold days, it doesnt work properly. Just for out the extra 15 - 20 and get a proper data bypass.

Me either... I dont see the point of using the relay, when you can just use a dmm, to check the resistance between the KEY side of the cut yellow wire, and a stripped part of the Black Wire, and get a corrisponding resistor, and add it to your alarm bypass wire from the R/S. All that relay business just sounds like more stuff to go wrong. By using the resistor in this fashion, you can get rid of the PassLock Warning light.

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The Only Stupid Question, is the one Un-asked

Forgot to add.... If you read his orig post, he has a Bypass mod, but it's not working. I'm just giving him options on how to check his Module, or get rid of it entirely... I spelled that wrong, I know   lol

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The Only Stupid Question, is the one Un-asked

The problem that you have here is that the 456GW does not do Passlock bypass. It is only designed to operate the locks/factory alarm/panic functions on '03-'06 full-size GM trucks.

What you should do depends on how easily you can return the 456GW...if you can take it back directly, do that and get a 457GW which will do Passlock bypass in addition to the functions that the 456GW will do. A 1700G or Bypasskit GMDL-BP will work also.

If you can't return it, you should get a standalone Passlock bypass such as the 555L, 556L, or Bypasskit PLJX, and continue to use the 456G for locks, etc.

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C Renner's Auto Electronix
My service is cheap, quick, and good - pick any two

Also agreed... all good input.... this is why I love this Forum

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The Only Stupid Question, is the one Un-asked

Thanks to all, I'll give it a go today. It looks like I was misled on the 456G interface module. I bought it off e-bay with the understanding that it bypassed the immobilizer as well as doing power locks.

Scott

I agree, it is the wrong bypass. Get the 457g or the 1700g like Chris says...

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Mike M2
Tech Manager
CS Dealer Services

As mentioned - it will depend on what you can find. Since DEI bought Trilogix(Bypasskit) they have stopped producing a lot of the DEI bypasses that duplicate Bypasskit's product functions.

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C Renner's Auto Electronix
My service is cheap, quick, and good - pick any two

I'm sorry, I'm a bit new at this...our 2002 Cavalier's Passlock II system is engaging for no reason, shutting off the fuel pump....I'm not sure what to do....I saw bypass kits for 50-60 dollars and I don't have that much money, but I guess I don't have a choice....I was wondering if there is anything I can do myself to get the car running and whether there was a cheaper form of bypass kit and where I could get one...

thank you

wjkreuser - unfortunately you can't use a bypass kit to permanently override any passive antitheft system, including Passlock. It will draw enough current to drain the battery excessively.

What makes you think that the Passlock is the problem?

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C Renner's Auto Electronix
My service is cheap, quick, and good - pick any two

Look at this.... https://documents.codesystems.com/700055.pdf if you need to Log in, use ID Alarmtech and the same is the password.  I didn't use the relays, I just tested the resistance between the yelllow and black wires, and added the corrisponding resistor on  OEM alarm bypass wire, then tied that wire to the Yellow Passlock II Wire

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The Only Stupid Question, is the one Un-asked

Hope that helps

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The Only Stupid Question, is the one Un-asked

As mentioned in my previous post - any bypass module or permanent Passlock bypass such as bbullers is referencing will not work with a malfunctioning Passlock system on the car, and cannot be used as a band-aid to avoid fixing the Passlock. Additionally, we haven't established yet that the Passlock is the problem.

wjkreuser again if you can specify why you think the Passlock is causing your problem, it would be very helpful. The Passlock system only stops cranking/fuel during the first few seconds after the key is turned to "start" position...it won't do anything for the rest of the run-cycle.

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C Renner's Auto Electronix
My service is cheap, quick, and good - pick any two

I was looking up the problem online and its similar to every other case involving the Passlock II. The Anti-Theft light comes on when its trying to start...the firing is normal...and I read that the fuel pump is disengaged by the Passlock II, which would explain why the car won't start despite the mentioned.

Ok...the first thing you should do is check all the fuses on the car, particularly those for the BCM and PCM.

The Passlock sensor, which is mounted on the ignition switch housing, sends its signal to the BCM during startup - if that signal is correct the BCM will send a signal over the data line to the PCM to enable fuel.

At any point recently was the car worked on, did anyone try to add something into it, or was a very large magnet placed near the ignition switch?

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C Renner's Auto Electronix
My service is cheap, quick, and good - pick any two

No, nothing changed....happened after a large thunderstorm the night before...

I tried starting it without the BCM fuse already with no luck

I guess I wasn't clear in my last post - I meant you should check all the fuses to see if they are blown.

If you haven't already, try disconnecting the battery for several minutes and then try to start the car.

If that doesn't work, let me know and I'll post or e-mail the Passlock learn procedure.

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C Renner's Auto Electronix
My service is cheap, quick, and good - pick any two

Did you ever get it going?

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The Only Stupid Question, is the one Un-asked