07 Silverado- Brake & ABS Light on

[Dschev1]

I have a 4.8 2007 Silverado with Flow master and K& N air .
I purchased the Pred. tuner with hopes to remove the delayed throttle response. I added the 93 oct. tune and drove for about 2 miles then my brake and ABS light came on. After reading through several topics I noticed the tire size adjustment would correct this issue. I adjusted the tire size (several times) then finally found the right size that would not turn on the lights. Ran and logged my tune then made adjusted to the injection slope and managed to get the fuel curve dialed in to 0 , -2 . Then I did the next best thing for more power and got a custom tune. I loaded the custom tune and had to re-adjust the tire size but finally got it to work (OCt 30 2008). Around Christmas I had to pull the tune and reload the original tune back into the truck. (Dealer Visit). When I reloaded the tune the lights were back on. I contacted the programmer of the custom tune and we worked or tried several different tire settings. ( we tried size ranges from 28-31.5) in .5 inch sets. I pulled the custom tunes from the truck and reloaded the original 93 oct. pwr. tune only adjusting the limiters to 130 and shutting off the DOD. The lights stayed off this time, I copied the tune and had it programmed with custom setting , then when I loaded the custom tune in the truck at 2.3 miles the lights were on again.
My questions are
1- Why when I first bought the programmer did I have to adjust the tire size to get the lights off ? and why wouldn't I have to do the same now? (there has been no changes to the truck)
2- WHy would a custom tune that worked in October not work when reloaded in Jan.
3- What do i need to do inorder to run my custom tune without affecting my brake & ABS lights..
Help PLease.....

[NIGHTSTALKER]

Try using the stock tire size, use the metric size. 265-70-17, or what ever it was. I had a prob with mine after installing my tune and tried to adjust the tire size and the same lights came on in my truck. I ended up setting my tire size back to the stock size and all is well now. May be when you went to the stealership they reflashed the ecm, and tcm, with an update. Which model pred do you have, new body style chevy or classic. I'm new to all this self tuning, but i'm sure that one of the more knowledgeable members may have a better answer.

[Dschev1]

Thanks for the input. I have the 2007 new style.with the U1794 Pred loaded with the 9r05 update. I didn't want to load the latest updates because I didn't have them during the original tuning process ( custom tunes).
I did try the stock setting I currently have tried custom tunes with all tire setting ranging from Stock down to 28 inch up to 32 inch tires. My truck came with 29.5 inch tires on it (265/70/17).I tried adjusting the tire size both by the metric setting and the inch setting. Where i'm getting frustrated or confused is we had it working fine from Oct. through Jan then after the dealer the visit ( repaired the window) now I can't get it right again. I talked with the GM at the dealer (Friend of mine) who stated the truck never got connected to the tech 2/ any other computer while there. (funny all they did was greased the rail).

[06MonteSS]

bump for DSChev...

any idea mike????

[CANUCKPREDATOR]

yeah any ideas, i could use a couple for my truck too.

[Dschev1]

OK People heres an update and hopefully some help to all those out there with the light problem. Its long winded so sit back grab a beer and smoke and read on------
But First things first--
I posted my issues with hopes of getting some technical / diablo suggestions on how to get my freaken lights to stay off. or atleast some humor like we are working on it or well have it solved by the end of the year or something-- come on now not like I'm asking for TCM support here now.... You could have humored me with something. Not responding showed that Diablo don't know how to resolve the issue-- a little advice usually kick starts somebody elses thoughts... sooner or later somebody would have made a suggestion that worked.
I don't know but if it wasn't for guys like MonteSS I would have returned my programmer and said the HeLL with it, it's not worth the headache. Don't get me wrong I think you have a good product here with nice pwr. additives but when there are issues pull it to gether and solve them- I don't think anybody expects you to have all the answers "right" the first time .. Just my thoughts though...... My opinion is if MonteSS isn't on your payroll you should add him. If it wasn't for him (guys like him) I wouldn't have gotten my lighting issue resolved... Can't say anybody from Diablo worked with me until 2am trying to solve this issue....If it sound like I'm bumping MonteSS your Damn right I aim- He's logged at least 100+ hours early morning, afternoon, and middle of the night helping me solve this issue with the lights...
So there now- with my venting out of the way
To my solution - Hopefully it works for some of you guys
I had the pred. tune installed working fine ( meaning no lights) once I upgraded to the custom tune the lights kicked on usually after about 2-3 miles of driving. We tried several adjustments both in inches (ranging from 28-32.5) and also tried using the side wall (metric 245-65-17 through 245-75-17) settings My tires are the stock tires at 29.5 inches or 245/70/17.
Here is what we did, I started driving the trk and stopping when ever the lights came on, I would adjust the setting by increments of 2 (meaning 245/68/17 and so forth). Finally I thought we had found the right combination of setting then after driving with the tires set at 245/72/17 the lights kicked on after 46 miles All city driven until 44 miles which is when I hit the expressway..... Reading through the postings listed on this site I found comments talking about DOD and so forth.. I have the 4.8 2007 Silverado new body style that does not come with the DOD but the programmer shows it as an option so I selected the DOD and turned it off.
After about two weeks of working TOGETHER and trying several different combinations my lights are off and the truck is running fine with the custom tune installed....
Final setting were
1- Custom Tune (only MonteSS knows those setting haha)
2- Adjusted speed limeter # 1 to 130 mph. (whenever I adjust # 2 lights come on ) don't make sense to me either....
3- Shut off the DOD option (my truck don't have DOD anyway) I spoke with the ecm technical support guys at work and they said if the tuner offers the option then it must be adding something to the program for the option-- which would explain why the lights stayed off while driving 40+ miles until I hit the expressway--once on the expressway then the truck would have wanted to kick into DOD mode without having DOD mode the RPM/pwr. bands would have self adjusted in the program resulting in a torque change triggering the lights... (maybe they couldn't say for sure)
4- Ran it at roughly 100 miles total now with no lights coming on.

Key points during adjustment to the tires & DOD are to go into the option screen select reset parameters on the custom tune/ load the reset to original tune parameters into the truck - start the truck and let it run a few minutes/ turn off the truck/ connect -reboot the pred. programmer)/ make adjustments once it boots up then load program back into the truck... Otherwise the pred programmer starts adjusting shit on its own when you go in a try adjusting the sizes without resetting to original..

Funny in October of 2008 I had never programmed a tune --- no I can talk or tune my truck in my sleep--- Thanks to the help of MonteSS...

[electrotyper]

I posted my issues with hopes of getting some technical / diablo suggestions on how to get my freaken lights to stay off. or atleast some humor like we are working on it or well have it solved by the end of the year or something-- come on now not like I'm asking for TCM support here now.... You could have humored me with something. Not responding showed that Diablo don't know how to resolve the issue--

What a cheap shot about TCM Support... I LOVED IT !!!!

[electrotyper]

I posted my issues with hopes of getting some technical / diablo suggestions on how to get my freaken lights to stay off. or atleast some humor like we are working on it or well have it solved by the end of the year or something-- come on now not like I'm asking for TCM support here now.... You could have humored me with something. Not responding showed that Diablo don't know how to resolve the issue--

What a cheap shot about TCM Support... I LOVED IT !!!!

[electrotyper]

SORRY! Didn't mean to say it twice... OR could I have done it subconsciously??

[06MonteSS]

WOW!!!

thanks man!! your good words are much appreciated!

...worked with me until 2am trying to solve this issue.... logged at least 100+ hours early morning, afternoon, and middle of the night...

and weekends, let's not forget weekends...

AAAHAHAHAA!!!

j/k man! hahah

[Dschev1]

oyea, Weekend and don't forget Christmas and New Years either.... You've got my vote

[podrup42]

I had the same prob i turned the DOD off and put the side wall height in and no more lights I took my truck into work and scanned it with my teck 2 and found it had set some weird frequency out of perameter code in the EBCM and i have a ? adjusting tire size will that change power out put in the tune

[Dschev1]

podrup42,
What I've noticed is depending on the tire size, I can tell a huge difference on the power band.
For an example I have two settings now that will run in my truck without kicking on the lights , set in metric size is equal to 31" tire has the speedo off by 2 mph but has good torq at low end but sucks at mid and top end.the other equals 29.2" tire with the speedo dead on and good pwr at low end and better at mid & top end but sucks at passing gear over 50mph.
GM has an update that will flash the ECM to larger tires but they charge you for that- My dealer is checking into getting me the flash and I'll post what type of charge they are looking for.
I found another issue with my truck.
According to all calculations my original tires should be 29.5" but according to the conversion calculation my new tires should have caused my speedo read 45 mpg when my actual speed was 47mph- in reality my speedo reads 45 but my actual speed is 43. My assumption is the original program was incorrect.
My actual speeds match a 265/65/18 tire when my truck was equiped with 245/70/17 tires. causing me (and Lew) nothing but a pain in the ass.....

[Dschev1]

http://www.csgnetwork.com/speedocalibcalc.html
Try this site, There are a lot of interesting calculators on this site- Scroll to the bottm of the page and hit automotive and you'll see what I'm talking about. You'll be able to enter your current sizes and compare it to what ever size you would like.
it will tell you what your speedo should be and the actual tire sizes. check it out you'll find good info here on the tire-light-abs issues...... Its where i found the difference between what my actual speeds are compared to what they should have been..
I know I haven't answered your question but I hope I've provided some info that might help.. I suggest getting in touch with 06MonteSS (Lew) or John/ Mike (Diablo) to get a better (accurate) response...

[podrup42]

Well my truck came with the 275/55/20 and that is the oem size allready in the ecm i work at a dealer i am one of the tecks and in order to reprogram tire size you have to call teck line to get a vci number and what is setting the code is the EBCM and ECM are seeing to different freq so reflashing the ecm may mess with the tune i am not 100% sure i am trying to talk with one of the software enginers at GM if I find anything else out i will post it