Passlock bypass options

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BrokenGQ

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'99 college party girl ('Hoe). She sucks good (k&n CAI), squeezes good (350 on a fresh build), blows good (flowtech LT's, true duals, cat delete, flowmasters), knows how to play the whistle (1" TB spacer), lights up the room (accel ignition system), and is built for speed (tuned by Mayhem Motorsports). But this fricken passlock man. It just started giving me problems this week. Crank, fire, stall, security light. Leave the key on until the light goes out and she'll start and run. I took the dash out to try and clean up the contacts and look for busted wires. I didn't find any problems. It's working now, but I'm sure I have less than a month before it's totally shot. Can anyone list actual ways to fix this? GM part replacement isn't an option, I don't want the problem again. And from what I've read unless I install a remote starter (which I don't want) I can't see a way around it. I'm good with electrical and from what I can tell just installing a resistor in the circuit will keep the passlock system active all the time, instead of just on start up, and I imagine will burn the system out sooner. Local stealership is refusing to tune it out of the BCM for liability reasons (don't want to be blamed for the theft of my truck) so I'm kinda stuck. I appreciate any help.
 

lesterl

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Find the wires in the column near where it bends check for breaks in the three wires there.....
 

sphillips

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For the last couple of years my 2000OBS would occasionally crank, fire, die. Let it sit for a while and it would start. A couple of days ago it did it again and happened to notice that with the ignition switch "On", the security light would flash. Looked in the manual and it said that Passlock had kept the engine from starting, but no info on how to remedy. I unhooked the negative side of the battery for about 20sec, hooked it back up and all good. Could be however the Passlock is wired inside the ignition switch is causing the intermittant start, but not sure.
 

DEzzell

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Small fix?

As a car audio guy, the ignition reads resistance through the key, so you can bypass that passlock with a resistor. I can't remember what the resistance is but any car audio shop can do this for you. It's the same solution if they were to install a remote start in your vehicle. Hope this helps.
 

lesterl

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As a car audio guy myself, the PCM reads the resistance of the internal pellet in the column (it wont be a fixed value, they use many and the resistance is stored in the PCM to be compared), the Resistance is read at a certian point in the startup cycle. The remote start system engages the resistor that is used as a bypass for a certain period of time to fool the PCM that the key is being used to crank the truck.

That being said, if you spend a few bucks on a PCM tune, you pick up some performance or MPG and you can have them turn passkey off in the programming....
 

sphillips

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As a car audio guy myself, the PCM reads the resistance of the internal pellet in the column (it wont be a fixed value, they use many and the resistance is stored in the PCM to be compared), the Resistance is read at a certian point in the startup cycle. The remote start system engages the resistor that is used as a bypass for a certain period of time to fool the PCM that the key is being used to crank the truck.

That being said, if you spend a few bucks on a PCM tune, you pick up some performance or MPG and you can have them turn passkey off in the programming....

Thx Lester, the Tahoe had an aftermarket remote start installed by some previous owner. No start issues since that event.
 
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