Accessing the computer on 01+ GM vehicles....or why I hate my new chevy

plumber mike

Adventurer
It's always sent me running in fear. The computer controlled vehicle. I'm now starting to build up several vehicles that use computer technology to stay running. I guess it's time I get some education........but where do I start?

The vehicles I am interested in gaining access to the computer........

2001 yukon xl 2500 8.1- aside from a service ride control message, yesterday I had it "reduce engine power". I'll need at least a code reader, but was thinking efi live to turn off the service ride control while I'm at it.

2014 Express 2500 6.0- I would like to turn off stabilitrak and traction control permanantly or this vehicle will have to be sold. I would like to adjust values on the TPMS, as 50 psi in the rear tires is not what I would consider low pressure for winter driving. It was a major disappointment, as the salesman said it could be turned off, but failed to mention it would turn back on every time the vehicle turns on or the wheel speed reaches 20 mph

2007 chevy tahoe 5.3- has been telling me to "service 4wd" for longer than I care to admit. The dealer recommended a reprogram, but that didn't work back when they did it under warranty. I'd like to pick up a few more ponies and a few more mpg's as well.

So, I Need to find something that is capable of reading codes. That's all dandy, but I also want to make changes to the computers, turn off torque management, and other things that I don't even know about yet.
Is efilive the only way to do this? Am I getting in way over my head? Would custom tunes from a company like Blackbear performance be a better option for a computer Noob? Is there a cheaper, easier way to turn off all the nanny features?

I've been putting this off for quite a while, but the new van purchase has pushed this to the top of my priority list. If I can't get these wheels spinning when I want them to, then this van, and any new GM will have no place in my driveway, and that makes me sad. There is a will, but what is the way?

Thanks all.

Mike
 

superbuickguy

Explorer
HPTuners is your friend. You can buy extra credits (the purchase price covers the 1st 3 vehicles) to cover all.... however, none of the aftermarket tuners work on the body control module - so abs system, the air bag system, and stuff like the daytime running lights can't be changed with that.

Which leaves you the snap on version of or the real version of a "tech II" - you'll hear much about tech IIs, it's a handheld that can get into most car computer systems... but be warned, they are spendy. There are knock-off Chinese ones that are not-so-bad pricewise, but I know of two being bought and have heard nothing from them since - they could work awesome, or they could be garbage (or somewhere between).

For your abs/traction control - pull the fuse, then it's off forever... IIRC (and you can verify this on HPTuner's forum - where you can get all sorts of tunes for your cars) you can "turn off" the reduce power request (uncheck the box)

with that said, the feds, of course, prohibit tampering with a federal required device (abs, traction control are such devices) - and while that is something to mostly ignore, some states (like Utah) can impound your vehicle if a cop stops you and sees dash lights for those fed. required devices.

Keep in mind, though, that playing with the computer system - you know that quip "dammit, you did it just like I told you to do?" with computers it goes double and you can burn your car down by changing things incorrectly - know what you're doing - but again, the HPTuners forum, the people there are pretty patient with noobs.

As for the TPS - there is no law that says you can't pull all your sensors and put them in your spare tire (well, there is, but I won't tell)... of course, finding a tire shop to do that can be a pain... but, and I live in evironaziland, if you have a regular shop where you get along well with the people (or, the gypsy tire stores as well)... they may "turn the other way" when you remove the sensors. If you do that, you need new, non-tps valve stems
 
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superbuickguy

Explorer
forgot one thing, there are professions where GM will turn off such things for you (LEO, RR companies, etc)... and, are you sure the nanny on your van is working to factory spec?
 

plumber mike

Adventurer
Thanks Superbuickguy! That will help me continue my education. I'll only lurk there unless I have a good question.

I have lived with warning lights on the dash for long enough that it doesn't bother me. I just don't want to miss a real problem that way. As I understand it, I could use resistors to fool a few things like autoride (worked well on my 2011 CTD exhaust temp probes and a little experience with H&S tuning) but it's my understanding they can be reprogrammed without the BCM or with changes to options that may or may not have come on a particular vehicle.

Pulling the fuse on the 14 is the cheapest solution for sure, but what a bummer on a brand new ride to have all the dash lights lit up like Christmas. As for the TPMS, I usually don't mind the little yellow light found on most newer vehicles, but these Chevys have to constantly remind you in the DIC as well!

Off to learn! Thanks again.
 

zoomad75

K5 Camper guy
It's always sent me running in fear. The computer controlled vehicle. I'm now starting to build up several vehicles that use computer technology to stay running. I guess it's time I get some education........but where do I start?

The vehicles I am interested in gaining access to the computer........

2001 yukon xl 2500 8.1- aside from a service ride control message, yesterday I had it "reduce engine power". I'll need at least a code reader, but was thinking efi live to turn off the service ride control while I'm at it.The reduced power message is probably due to a throttle control problem, most generic code readers should be able to get you the code so you can diagnose further. As far as the service ride control message, EFI live probably won't touch it. On that vintage of truck the ride control has it's own module that has limited diagnostic capability. Typical problem is the compressor (which contains the module) dying due to a leak in one of the rear shocks or line to either that caused it to run constantly, overheat and nuke itself. Fix is to replace the compressor and fix the leak.

2014 Express 2500 6.0- I would like to turn off stabilitrak and traction control permanantly or this vehicle will have to be sold. I would like to adjust values on the TPMS, as 50 psi in the rear tires is not what I would consider low pressure for winter driving. It was a major disappointment, as the salesman said it could be turned off, but failed to mention it would turn back on every time the vehicle turns on or the wheel speed reaches 20 mph The dealer can't even turn stabilitrack/traction control. For the tire pressure monitoring, thank the FEDS for that one. ALL vehicles are required to have tire pressure monitoring. Any salesperson that would have told you it could be shut off is an idiot. Up to 2010 dealers could adjust the pressure values by going in with the Tech2 and selecting another type of tire that had a different pressure value, but GM locked it down in 2011 and later vehicles.

2007 chevy tahoe 5.3- has been telling me to "service 4wd" for longer than I care to admit. The dealer recommended a reprogram, but that didn't work back when they did it under warranty. I'd like to pick up a few more ponies and a few more mpg's as well. Here's an idea, get the problem diagnosed and fix the problem...Sorry for the smart response but it's that simple. The 4wd system is pretty simple. Could be the switch, TCCM, encoder motor or an internal problem in the t-case. The codes set in the TCCM will give the direction needed. Programming can help, but it won't fix a problem that is causing it to set a code in the first place.

So, I Need to find something that is capable of reading codes. That's all dandy, but I also want to make changes to the computers, turn off torque management, and other things that I don't even know about yet.
Is efilive the only way to do this? Am I getting in way over my head? Would custom tunes from a company like Blackbear performance be a better option for a computer Noob? Is there a cheaper, easier way to turn off all the nanny features?

I've been putting this off for quite a while, but the new van purchase has pushed this to the top of my priority list. If I can't get these wheels spinning when I want them to, then this van, and any new GM will have no place in my driveway, and that makes me sad. There is a will, but what is the way?

Thanks all.

Mike

It's the way of the industry now, not just GM. ALL manufactures are required to comply with emissions/fuel economy requirements. That's brought us the OBD2 fun and then you add mandates for tire monitoring along with new mandates coming down the pipeline for stability systems and even back up cameras you aren't going to avoid it. It does not matter if you look at Ford, Dodge or any of the foreign brands. You should be able to deal with torque management with aftermarket tuning software, but they won't reach into the "non-powertrain" type controllers. The only way to fully avoid the nannies is get something much older, pre-obd2. Best of both worlds is getting a solid pre-obd2 base vehicle and update the powertrain with modern engine/trans running aftermarket controls or modified stock controls with the nannies tuned out.
 

Kaisen

Explorer
"Reduced Power" in the Sub 8.1 is most likely the throttle body itself, but might also be the pedal throttle position sensor (TPS).... either one will throw it into the limp mode that will show the reduced power display. They are throttle-by-wire and all inputs and outputs must match or they will failsafe (govt mandate). Turning the truck off should reset the input/output values and allow them to synch again. Should drive fine for awhile then may fail again when one of the values doesn't match again. Fix the issue.

The "Service Suspension" is the Autoride system. You can ignore it, fix it, or bypass it (replace shocks with conventional, unplug compressor, ignore light). Either way, it's not working.
 

plumber mike

Adventurer
Thanks for telling me what I didn't want to hear:Wow1:
Very educational look into the newer vehicles. I guess I've got some "for sale" signs to buy.
 

plumber mike

Adventurer
"Reduced Power" in the Sub 8.1 is most likely the throttle body itself, but might also be the pedal throttle position sensor (TPS).... either one will throw it into the limp mode that will show the reduced power display. They are throttle-by-wire and all inputs and outputs must match or they will failsafe (govt mandate). Turning the truck off should reset the input/output values and allow them to synch again. Should drive fine for awhile then may fail again when one of the values doesn't match again. Fix the issue.



The "Service Suspension" is the Autoride system. You can ignore it, fix it, or bypass it (replace shocks with conventional, unplug compressor, ignore light). Either way, it's not working.

The reduced power message came during a mini blizzard, and I parked it in a heated garage. I'll try to reset it today. I also found a how to on the autoride that uses resistors from radio shack. Going to try it.

What are you guys using for a basic code reader? I'll pick one up for the wife's POS, but I can't help think there has to be a way to write that out for trucks that use a lever instead of a button. How would a guy upgrade to an actual lever style transfer case without sending the computer into a tizzy?
 

superbuickguy

Explorer
I wouldn't because the stepper motor is more reliable than linkages - however, IIRC, there is a kit for your transfer case to use a cable rather than the stepper motor... presuming it's a 4L80e, you could swap in a Ford transfer case (with the corresponding GM input shaft) or 88-98 Chevy truck transfer case to get you roughly what you're looking for... honestly, it's a lot of work and money - and if you're worried about the stepper motor, carry an extra - they are really easy to change in the wild.
 

Kaisen

Explorer
But that's not "EXPEDITION GRADE"..... it *MUST* have a lever, crank windows, rubber floors, and you have to be able to set the spark advance from the steering wheel with a brass lever. Oh, and the tallest skinniest tires you can find.
 

Larry

Bigassgas Explorer
I wouldn't because the stepper motor is more reliable than linkages - however, IIRC, there is a kit for your transfer case to use a cable rather than the stepper motor... presuming it's a 4L80e, you could swap in a Ford transfer case (with the corresponding GM input shaft) or 88-98 Chevy truck transfer case to get you roughly what you're looking for... honestly, it's a lot of work and money - and if you're worried about the stepper motor, carry an extra - they are really easy to change in the wild.

But that's not "EXPEDITION GRADE"..... it *MUST* have a lever, crank windows, rubber floors, and you have to be able to set the spark advance from the steering wheel with a brass lever. Oh, and the tallest skinniest tires you can find.

because everyone knows that you can dig down to traction with them skinny tires... :wings:

histerical.gif
You got to be kidding me. Sounds like you two have no real world wrenching for a living experience or real world off-road experience but I could see how city slickers would like those buttons, dials, electric this, automatic that, blah, blah blah. Perhaps, you two are spending time on the wrong website?? This genesis of this website and forum is about vehicle depending off-road travel where durability and reliability is key.

Seriously, while we all love technology and the reality is technology has made modern vehicles much more reliable than they were 30+ years ago, but there are certain components in the vehicle that should be left low-tech because certain technology takes away from the reliability. That is just the case with electric shift 4x4 or electric shift transmissions in the case of RAM 1500 8 speed trucks and most new Chrysler vehicles. You will have a hard time convincing a professional auto technician, someone who got stranded off-road because a button wouldn't shift into 4hi when the snow got deep, the RAM 1500 owner whose truck rolled into a pole when he turned that electric dial into Park and stepped out only to see his truck roll away into a tree because the "shift" motor never really shifted into Park or someone that had to drive their new $62,000 Suburban back to the dealership in in 4low because the stupid electric shift tranfercase control module decided to shift on its own with a random ignition key cycle and got stuck in 4low (in fact, GM has a bulletin for just that on '14 & '15 model year 4x4s) that fancy needless electronic switchgear technology is better and more reliable than the good old levers, linkages and cables just like you will never convince me carburetors and breaker point ignition are better than fuel injected computer controlled engines. Technology has its place but not everyplace. There needs to be some mechanical interface on certain components.
 

superbuickguy

Explorer
histerical.gif
You got to be kidding me. Sounds like you two have no real world wrenching for a living experience or real world off-road experience but I could see how city slickers would like those buttons, dials, electric this, automatic that, blah, blah blah. Perhaps, you two are spending time on the wrong website?? This genesis of this website and forum is about vehicle depending off-road travel where durability and reliability is key.

Seriously, while we all love technology and the reality is technology has made modern vehicles much more reliable than they were 30+ years ago, but there are certain components in the vehicle that should be left low-tech because certain technology takes away from the reliability. That is just the case with electric shift 4x4 or electric shift transmissions in the case of RAM 1500 8 speed trucks and most new Chrysler vehicles. You will have a hard time convincing a professional auto technician, someone who got stranded off-road because a button wouldn't shift into 4hi when the snow got deep, the RAM 1500 owner whose truck rolled into a pole when he turned that electric dial into Park and stepped out only to see his truck roll away into a tree because the "shift" motor never really shifted into Park or someone that had to drive their new $62,000 Suburban back to the dealership in in 4low because the stupid electric shift tranfercase control module decided to shift on its own with a random ignition key cycle and got stuck in 4low (in fact, GM has a bulletin for just that on '14 & '15 model year 4x4s) that fancy needless electronic switchgear technology is better and more reliable than the good old levers, linkages and cables just like you will never convince me carburetors and breaker point ignition are better than fuel injected computer controlled engines. Technology has its place but not everyplace. There needs to be some mechanical interface on certain components.

oh yeah, you got me... I've never built a 70 Buick Skylark, a 62 Buick Skylark, 7 S-10 V8 Blazers, countless chevy pickups, an H3 Hummer, a FJ40 (my 8th), a 50 buick sedanet, a Fiat Spider with a twin turbo CTS Cadillac motor, several C3 Corvettes... but outside of that, there was that whole flipping car period of my life that included VWs, Hondas, toyotas and anything else I could make a buck on.

But you're next line will be about my lack of offroading... funny, both Search and Rescue organizations I'm part of think I know what I'm doing - but you, keyboard jockey, will set them straight... they'll feel so foolish.

All you do is run your mouth, Larry, if only you knew what you were talking about.
 

toylandcruiser

Expedition Leader
histerical.gif
You got to be kidding me. Sounds like you two have no real world wrenching for a living experience or real world off-road experience but I could see how city slickers would like those buttons, dials, electric this, automatic that, blah, blah blah. Perhaps, you two are spending time on the wrong website?? This genesis of this website and forum is about vehicle depending off-road travel where durability and reliability is key.

Seriously, while we all love technology and the reality is technology has made modern vehicles much more reliable than they were 30+ years ago, but there are certain components in the vehicle that should be left low-tech because certain technology takes away from the reliability. That is just the case with electric shift 4x4 or electric shift transmissions in the case of RAM 1500 8 speed trucks and most new Chrysler vehicles. You will have a hard time convincing a professional auto technician, someone who got stranded off-road because a button wouldn't shift into 4hi when the snow got deep, the RAM 1500 owner whose truck rolled into a pole when he turned that electric dial into Park and stepped out only to see his truck roll away into a tree because the "shift" motor never really shifted into Park or someone that had to drive their new $62,000 Suburban back to the dealership in in 4low because the stupid electric shift tranfercase control module decided to shift on its own with a random ignition key cycle and got stuck in 4low (in fact, GM has a bulletin for just that on '14 & '15 model year 4x4s) that fancy needless electronic switchgear technology is better and more reliable than the good old levers, linkages and cables just like you will never convince me carburetors and breaker point ignition are better than fuel injected computer controlled engines. Technology has its place but not everyplace. There needs to be some mechanical interface on certain components.

That's just because it's a dodge :)


Sent from my iPhone using Tapatalk
 

plumber mike

Adventurer
But that's not "EXPEDITION GRADE"..... it *MUST* have a lever, crank windows, rubber floors, and you have to be able to set the spark advance from the steering wheel with a brass lever. Oh, and the tallest skinniest tires you can find.
I just want the vehicles to work. Not a big request, really. Or so I thought. Carpet or rubber floor, plastic or brass lever. It doesn't matter. It's a sad day when my old snowplow truck is my most reliable vehicle. It was also the cheapest. I've owned it the longest, so I know it's been beat the hardest. I'm not asking the newer ones to do anything that one hasent done, but I expect them to be able to bust some fresh tracks to town without so much drama and failure.

So I post up here, to hopefully find a way to turn off the failing features, or find out what others have used to replace the failing features. It's sad to hear you just learn to live with them.
 

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