im back with results haha.

well the maf was bad, changed it but, the scanner with the scanxl pro gave me some realy interesting codes, specially one related with the no start condition:

Trouble Codes

P1602 Serial Communication Problem With Device 2
P1610 Serial Communication Problem With Device 10
P1626 Theft Deterrent Fuel Enable Signal Not Received , this one worries me, it cause the no start condition.
U1301 Class 2 Data Link High
C1298 PCM Class 2 Serial Data Link Malfunction , this one i think is the trac off it got activated after the car got towned.

Pending Codes


P1602 Serial Communication Problem With Device 2
P1610 Serial Communication Problem With Device 10
P1626 Theft Deterrent Fuel Enable Signal Not Received , this one worries me, it cause the no start condition.

Your P1610 not communicating with device 2(I'm guessing BCM) not getting the fuel enable code is probably it.

All modules are connected via daisy chain on a Class 2 serial bus. If you cut the connection, all hell breaks loose. I've seen some BCM'* fail so bad, that it cuts itself out of the communication circle.

Your about to become very friendly with some schematics of your car and a DMM.

oh god, so i need to search the cables and conections?, do i need to replace the bcm?

please help ):.

guide me thru this pain.

Not unless you know someone with a Tech2. Those scanners/programmers are designed to "ping" each module and make them do self tests. If the Tech2 can't operate a module, more than likely its the culprit.

wow, to be honest i dont know anyone with one of those.

but just to know, whats the process to check and repair that failure?

cause even if i replace the bcm the failure will still be there right?

No process. External test equipment is needed to test each module for failure. The Tech2 can tell which module is bad. IF it is bad. Sometimes a bad ground can cause a module to fail, and cause a condition as this.

i see, well what can i do if i cant locate someone with tech2?

Honestly, if your asking that question, take it to a dealer. Diagnosing a condition such as this isn't exactly easy to teach over the internet. A background in automotive electrical systems, electronics etc is needed.

Ok.

What are the possible solutions to this problem, after a propoer diagnostic is done?

You really need to get a diagnosis before we can really help.

Because the remedy will differ depending on what the cause is.
It could be a failing passkey sensor, or the BCM itself.
One will require you to replace the ignition switch, which is not too easy for a DIY job, I'll give you a link to look at to see what you'd need to do if it was the ignition switch.
Your key does not have a visible pellet it it right?
I ask because I am pretty sure you have Passkey 3 and not Passkey 2.

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If it is the BCM then they would be easier to replace, but they are not cheap, and they need to be reprogrammed once installed, and in your case you'll most likely need the dealer to do it.

The thing I do not understand is you mentioned the car shut off while running, I guess that could have been from the faulty MAF, but the theft deterrent signal issue will not shut the car off while running, but it will prevent it from starting once shut off.

If it is diagnosed as a bad BCM, I think you can have somebody that tunes PCM'* tune VATS out of the system, that would be cheaper than replacing the BCM, you'd lose the security system though..