Theft Recovered Suburban --- No Start

[krandall]

I purchased a theft recovered 99 K1500 Suburban. They were in the process of stripping it and got caught so most of the parts were inside it. THe major problem is they stole the computer and cut 2 of the wiring plugs that went to it. We purchased another engine wiring harness and computer from a same year , make and model suburban with the same engine , trans., etc. The engine will start for a second or two and then die. The security light is also on. I was told I might have to take to a dealer to have my computer programmed. Does anyone have any ideas on this mess ?

[95Sierra2500]

You have to remember that by '99 most vehicles had a type of anti-theft system that made it more difficult.

 

I'd suggest that, if you haven't tried it, unhook the battery for a few minutes (make sure it's fully charged), then hook it back up. I had the battery die on my old '99 Jimmy, and simply jumping it didn't work, it set off the security system. I ended up having to disconnect the battery to reset the computer.

 

If that doesn't work, I'd suggest taking it to a dealer to have a Case Learn performed. It could be that the computer learned the old engine, but now doesn't know this engine and will not let it start.

 

Last resort is a computer re-flash, but you may end up at this point.

[keebler]

I purchased a theft recovered 99 K1500 Suburban. They were in the process of stripping it and got caught so most of the parts were inside it. THe major problem is they stole the computer and cut 2 of the wiring plugs that went to it. We purchased another engine wiring  harness and computer from a same year , make and model suburban with the same engine , trans., etc. The engine will start for a second or two and then die. The security light is also on. I was told I might have to take to a dealer to have my computer programmed. Does anyone have any ideas on this mess ?

 

<{POST_SNAPBACK}>

 

 

 

Off the top of my head...

 

These vehicles have the Passlock security system. There's a resistor in the ignition switch that the computer expects to see when you start it. What you've described with the Security Light being on, and the computer having been replaced, and running for just a few seconds sounds like the security system.

 

The resistor in your ignition switch doesn't match the resistor the replacement computer is expecting -- it thinks you've hotwired the truck so it shuts down.

 

The Passlock system is designed to prevent engine operation if the correct key is not used to start the vehicle. The ignition key turns the lock cylinder, cylinder rotation produces an analog voltage code in the Passlock sensor.

 

The EVO/Passlock module receives this voltage code and is compared to the last learned voltage code. If the codes match, the EVO/Passlock module sends a class 2 message to the VCM/PCM, enabling the fuel injectors.

 

There's a 30 Minute proceedure to re-train the computer. (Or 10 Minutes if you have a Scan Tool.) I'll look it up and post it in another message below...

[keebler]

The following procedure allows for anyone to reprogram the EVO/Passlock™ module learned data code with any tools, other than the scan tool, when any of the following parts are replaced:

 

- The EVO/Passlock™ module

- The passlock™ sensor

- The VCM/PCM

 

 

 

The following is the Auto Learn Procedure:

 

1) Insure the ignition key is in the ON position.

 

2) Clear all EVO/passlock™ module and VCM/PCM DTCs. Record and refer any VCM/PCM DTCs to:

- For 5.0/5.7L engines, refer to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls - 5.0/5.7L

 

3) Momentarily rotate the ignition key to the CRANK position (Do NOT start the vehicle), then release it to the RUN position (Do NOT key OFF in the process).

 

4) Wait 10 minutes. Observe the SECURITY indicator. Refer to the following list for the appropriate responses:

- If the passlock™ sensor was replaced the SECURITY indicator will flash for the 10 minutes duration.

- If the EVO/passlock™ module was replaced, the SECURITY indicator will flash for a few seconds and then remain ON for the remainder of the 10 minutes duration.

- If the VCM/PCM was replaced with a new programmed VCM/PCM and connected to the vehicle for the first time, the vehicle will start and this procedure may not be necessary.

- If the replacement VCM/PCM was connected to any vehicle at any other time, even momentarily, the SECURITY indicator will flash for a few seconds and then remain ON for the 10 minutes duration.

 

5) The SECURITY indicator will transition from flashing to ON briefly to OFF after 10 minutes if remaining in the ignition ON position.

 

6) Turn the ignition switch to the OFF position and wait for 10 seconds.

Repeat steps 3-6 two more times. The new security code is ready to be communicated among the Passlock sensor, EVO/Passlock module and VCM/PCM.

 

7) The new password is learned on the next ignition lock cylinder cycle from OFF to CRANK to ON (start attempt).

[krandall]

I wish I would have seen this message before I took it to the dealer today. I bet it would of worked. When I got my replacement PCM , I got one from an almost exact twin with the same drivetrain, gearing and options. I will let you know what happened.