Chevy does NOT recommend "ScanGauge II" for Sonic

LorbeerTLC

LorbeerTLC

Member
Well, I just learned that my Chevy dealer thinks it's unwise to hook up my ScanGauge II to my Sonic and he has a valid reason

ScanGauge - Trip Computer + Digitial Gauges + ScanTools

For the past two months, I've been getting the monthly OnStar diagnostic reports and everything has been highlighted with yellow triangle alerts saying it couldn't process the diagnostics because a third-party device was using the OBD II port.

I use ScanGauge II because I like to see what the coolant temperature and the voltmeter is on my Sonic. It's a shame everything has "idiot lights" with the only gauge being for fuel.

Here's what the Operations Manager opinion was and I believe he may have a point:

"Tom,
Regarding the use of an aftermarket device that connects to the ALDL for monitoring performance is a little bit scary.
When this is into the connector it “over rides” the communication of the vehicle with control devices.
That being said the possibility exists that air bags will not deploy in a crash because the system thinks you are in diagnostic mode.
I recommend against its use.
GM does not make an accessory gauge package to my knowledge, and I understand your desire to monitor.
If there were an aftermarket pack that you find perhaps I could look at how it connects to the vehicle.
That is the only way I could tell you there would be no problem upon install. It might interfere with fail safes built into the ECM.
For example the oil pressure is monitored and the engine can go into a passive mode if it detects loss of pressure.
If another device is in the system I don’t know how it would work or if it would trigger a fault code.
With the capabilities of your car, the on board computers should alert you to an issue before it becomes a problem
It can detect a misfire without you or I ever feeling it and turn on the check engine light. It does more than just allow capture data to be stored."

Butch Smith
Fixed Operations Manager
Roy Robinson Inc

So now I'm looking into an alternative like maybe installing a set of VDO gauges.
VDO - We are a leading international supplier of OEM and aftermarket solutions.

We'll see what happens… :popcorn:
 
BNRacing

BNRacing

Supporting Vendor
This happens with any obd2 stuff plugged in. I did progressive snapshot for the insurance discount and my onstar would do the same thing. All comes down to what you'd rather have. I personally don't care about the onstar reports, I just want them to respond if there's and accident.
 
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oldertech

New member
Well that's a head scratcher. I had no idea that my UltraGuage could cause an ECU issue. Is there any way to verify that is could mess up air bags from GM?
 
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laborsmith

New member
Per Butch Smith: "I don’t know how it would work..."
Butch Smith is the Operations Manager whose response is included in the original post.

When I took the Sonic in to the dealership for the first oil change, I had the UltraGauge velcroed to the instrument cluster, and there was no comment from the service personnel.

I am not enrolled in the OnStar monitor program as I am a paranoid person who has little trust in big anything to have my interests at heart. But I do know OnStar works because I will call in to get directions every once in a while.

I would say the only way to determine if the air bags are disabled is to drive into a solid wall at speed with something plugged into the port, something I am not willing to do nor recommend anyone else try.

And we should not forget that GM including Chevrolet has a vested interest in promoting OnStar.

And I question making this a sticky.

Laborsmith
 
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oldertech

New member
laborsmith said:
Per Butch Smith: "I don’t know how it would work..."
Butch Smith is the Operations Manager whose response is included in the original post.
Click to expand...
Sorry, I missed that he was with GM. When I got the first email that said OnStar couldn't read my car's status, I poised the question to UltraGuage. Here is the response.

Date: 02-10-2012 08:48:48
Name: UltraGauge
Message:

GM has known about this issue since before 2004 and they have chosen to do nothing to correct it. Unfortunately, there is nothing we can do as their On-star diag does not function in the presence of external devices. We suspect this is on purpose as they want to sell the on-star service and external devices are competition. No other functions of On-star are affected. Note that UltraGauge constantly monitors for trouble codes while you drive, as opposed to once a month like On-star.

Best regards,

UltraGauge Support
UltraGauge Automotive Information Center and OBDII Scan Tool
Support is available Monday-Friday, 9-5pm Central Time
 
LorbeerTLC

LorbeerTLC

Member
The point is, new cars are driving computers. Everything is linked to the point that I don't fully understand how it all works anymore.

My automotive comprehension stopped after the 1990's when there was an electronics boom in automobiles. The old days of tuning-up my 1966 Plymouth Valiant with the 225 slant six engine are golden! Kids growing up today probably look at a car like that about the same way as I would see an old Ford Model "T."

Open the hood on a brand-new car and my first glance is to see if I can find the dipstick. Heaven help us if they decide to do away with those and replace it with a "sight-glass" (like they're doing on some motorcycles). :eek:

My biggest insecurity on a new car is the electronics and while my common sense tells me that it's probably ok to leave the ScanGauge II connected, I'm certainly no technician. And with the OnStar Vehicle Diagnostics monthly report telling me that ever since I plugged the ScanGauge II into the OBD II port, it's now unable to connect or run a diagnostics on the car… along with Butch's cautious comments… that's good enough for me to unplug it.

The other imposing factor is should I experience problems later on, GM might say that because I have a foreign device plugged into the OBD II port they won't honor the warranty. So why risk it? I love my new Sonic and I want to keep it as long as possible with little to no problems. :D
 
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omniman

New member
I have a scan gauge II also.Bought it for my Aveo if there was a problem with the Airbag it would set a code and turn on the airbag light which is always being monitored.If you look at were it plugs in each pin is for something different ground, power, and computers. But as a diclaimer I work for GM as a tech and cant say will or will not cause airbags to not go off or Onstar not to perform crash responce. But I use mine and love it.
And will do some research on it.
 
wingman

wingman

Active member
My ultra interfering with monthly diagnostics didnt bother me, but as a safety issue I might have to remove it. :(
 
LS1notFOUND

LS1notFOUND

New member
Bit lengthy but this is what an afternoon where you are a bit sick and sitting in front of computer is about all you feel like doing...

Depends on the device I'd think, basically probably the scan gauge causes the OBD II single/bus to give OnStar a busy signal.

Would all the automated features of crash response work? OnStar may not get the signal should something happened. I'm sure airbags would deploy because if they have an issue the dash light would be lit or it would indicate an issue at initial start up. If not, this is a bigger issue.

Basically your always pulling information from the computer when that's plugged in, it listens, the dash board is listening, other modules are listening, the scan gauge could possibly leave the vehicle in diagnostic mode or something similar because your literally using a scan tool the whole time its plugged in

In 04 up Grand Prixs people would pull radio and other electronic fuses before flashing the PCMs for a tune because, albeit rarely, you'd have "cross traffic" interfere with the flash from other modules etc.

I had an issue with an aftermarket Axillary in unit that would play and randomly which off and disappear from the radio options because of the Scan Gauge, unplugged all was well. Changing aftermarket AUX brands fixed that however and Crutchfield was great to troubleshoot with.

MY 98 Firebird would leave the scan gauge on if I didn't unplug it, the Grand Prix would boot it up and turn it off with the turn of the key....however once in a blue moon it cause some funky things with gauge cluster to cease proper function and that a key off door open unplug the gauge would have to be done.

The gauge wouldn't read oil pressure on either vehicle if memory serves correctly.

Scan Gauges are about 200 bucks right? You can get decent temp and oil pressure gauges tapped into the actual source/sensors (not always the case but hopeful) for nearly the same I would think and have a Gauge pod of some sort.

Don't get my wrong, I loved my scan gauge II, it was great knowing when i got a bad tank of gas and I would get 18 degrees of knock at WOT [wide open throttle] but its a vehicle to vehicle thing if it will work 100% as vehicle to vehicle you have different computers that talk with the other computers...differently. A Cadillac or BMW with more computers and sensors than you can shake a stick vs our Sonics which probably have 1 computer do most of the work is going to act differently, when you throw another device in the mix.

The simple solution is to only use the gauge when your doing "out of warranty" or lesser evil "spirited driving" that actually needs monitoring. Actually have it not connect with onstar during those activities and possible keeping the real time date off the PCM would be handy....

Crusing 70 down the freeway and having a look at battery volts doesn't need to be monitored as closely as oil pressure or temp when your hot lapping the Glen or Road Atlanta.

Now I've discovered a coolant issue as I watched the temp gauge rise or failed alternator as my volts drop and drop before the little "check gauges" like would come on but most vehicle dashes on todays cars are simply "dummy" gauges. All listening to the same function of dash lights. Coolant temp on some vehicles is simply cold to the left, up to temp strait up, over heating detect throw on a light, send needle right, it doesn't actually follow real temp, but a filtered version of volt numbers and the computer tells it where to go...seems over complicated to me really.

Also try unplugging the gauge when the vehicle is parked for extended periods (over night/in the lot at work, watching titanic in 3d and enjoying the sinking scene) and see if the OnStar e-mails begin to work correctly. They usually come to my inbox when mines parked and I can check fuel, range, tire pressure, unlock the doors, panic from my phone as long as I have cell signal so something in there is awake all the time
 
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laborsmith

New member
It occurs to me that the diagnostic mode does not disable tpms which can not be disabled due to safet without causing a response (both on the DIC and a chime) and as there is no such reaction to an Ultragauge (cousin to Scangauge) for the air bags, I have decided that using the OBDII port will not interfere with these two safety elements but will certainly interfere with some of the OnStar monitoring.

Laborsmith
 
LorbeerTLC

LorbeerTLC

Member
Laborsmith,

Is there anything official like a Service Bulletin from GM that I can pass this information along to my servicing dealer?

Before I plug mine back in, I want to have something written from GM as to not possibly conflict with a warranty issue down the road.

Otherwise, I'll take a safer route and probably install gauges directly to the sending units, like the ones you'll find at VDO.

VDO - We are a leading international supplier of OEM and aftermarket solutions.

Thanks! :)
 
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laborsmith

New member
Lorbeer, I am not sure what I wrote that would lead you to ask about a Service Bulletin from GM, but to answer your question, I am not aware of such.

Another thought: there is an insurance company (Flo is the spokesperson) that advertises a part that plugs into the OBDII port and keeps track of drivers habits; ostensibly one gets a discount if one avails themselves of that. I suspect that if it interfered with the operation of an airbag or any group of airbags that an insurer selling auto insurance would not be promoting the use of the device.

Laborsmith
 
SteveSonic

SteveSonic

New member
laborsmith said:
Lorbeer, I am not sure what I wrote that would lead you to ask about a Service Bulletin from GM, but to answer your question, I am not aware of such.

Another thought: there is an insurance company (Flo is the spokesperson) that advertises a part that plugs into the OBDII port and keeps track of drivers habits; ostensibly one gets a discount if one avails themselves of that. I suspect that if it interfered with the operation of an airbag or any group of airbags that an insurer selling auto insurance would not be promoting the use of the device.

Laborsmith
Click to expand...

That's a really good point, Laborsmith
 
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