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What does OnStar know?

BlackSilver

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BlackSilver Senior Enthusiast

BlackSilver

Posted
Posted

My truck lit the SES lamp yesterday afternoon, so I asked OnStar to run a diagnostic check.

 

They reported back that they found "a problem in the power-train control and management system, but that other systems would compensate for the problem.  It is OK to drive the vehicle but get to a dealer within 7 days".  I don't know if they had a trouble code or not, but if they did, they would only report their "canned speech".

 

The dealer ran diagnostics and found no power to the glow plugs.  A nut was loosely attached under the fuse panel.  Tightened it down, and problem cleared.

 

At least the OnStar check gave some confidence in that I could continue to drive the vehicle, but I guess I'd have liked more detail.

CMNTMXR81 Senior Enthusiast

CMNTMXR81

Posted
Posted

With OBDII, all they can tell at this time is what the "general" problem is.  As long as your cranking system, charging system, fuel system, and ignition system (you don't need to worry about this) all work, you could drive it till the wheels fall off with all the idiot lights on, on the dash for all anyone cares.  They just have to say that (7 days).  They figure you're not gonna run right over to the dealer to get it fixed but figure within a week you should be able too.

 

Now when OBDIII comes on board in the next 3-4 years, they will be able to give more specific info as well as report it to the proper EPA authorities if deemed necessary (say if you don't fix the problem for a month) if it's an emissions related type problem.  Another thing they'll be able to do, is monitor all vehicle parameters in real time.  I.E. speed!  They can then alert the local authorities who can then intercept you.

 

In reality, While on GM's side they may be able to do this, I can speak for the State of Illinois, that they do not have the funding for the EPA, State Police, County Police, and local Police to get all of them online with this system.  Hence, I highly doubt all the doom and gloom you're hearing about it will come true.

 

This was a similar scenario in the mid 90's when OBDII was on the platform about to be launched!  Everyone screamed about "more control to big brother" and how it'll be the death of the performance industry because it was supposed to be more stringent than OBDI.  Turns out, it was a blessing in disguise.  The more complete and inclusive parameters an OBDII PCM allows, allowed more real time data acquisition (as well as logging) that us performance enthusiasts can use to fine tune our vehicles.  When performing a mod, instead of blindly thinking it worked, with OBDII, if you threw an SES code, you knew the mod you did either A) didn't work or B) gave you sufficient info to adjust other parameters to MAKE it work.  

 

At the same time, it has made emissions testing considerably easier.  I'm not sure if you know this, but up until recently, most state's and large metro areas had adopted a test called the IM240 roller test.  It was essentially a dyno run that mimmicked everyday driving situations while at the same time sampling exhaust gasses (sniffing).  With OBDII (96+), many metro areas (Chicago included) now only use the IM240 as a backup test.  Now an OBDII scan is done into the PCM.  You pull up, they do the standard visual inspection and gas cap test, pull you forward, connect a PC to your DLC data port under the dash, 15 seconds later you pass or fail.  It checks for DTC's and for readiness monitors being all active.  I've done this already with the Camaro.  It was fantastic!  No worry about some incompetent, high school dropout, f*cking up your car on the dyno.  This almost happened to me with my Bravada (AWD).  The emissions jockey insisted on putting it on the dyno despite my repeated arguments that it's AWD and if you put it on that dyno, the State will be paying for my broken drivetrain parts.  Finally after enough screaming, the Supervisor came over and basically told the jockey that I was right, this vehicle was AWD and that it could not be roller tested.  With this new OBDII PCM test, this is all avoided.  You're in and out in less than 2 minutes total.  Before it was about 5-10 minutes per vehicle to strap it down, perform the driving test, unstrap it, get your pass paper and go.

 

I feel the OBDIII system will also turn out to be a blessing in disguise.  Of course you'll get those conspiracy theorists, you know the ones that freak out over black helicopters, complaining about Big Brother being able to watch us.  "Whatever", I say...I've got nothing to hide.

 

To sum it up, don't worry about what OnStar can know.  They do not posses the manpower or constant time to monitor every OBDII PCM on the road.

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