PCM reset methods??

Yes, Forscan should do it.
Calibration shouldn't be needed unless the ABS module was changed or the yaw or steering sensors. If it's had this problem since you bought it, then this could be a part of the problem.
 
FWIW..before I ever went to the dealership, I had pulled the front wheels to try and clean and re-grease the sensors and connection. Obviously this didn't work, as they needed to be replaced. But, I noticed that my front driver side was the standard clip-on (2002) but my front passenger was the bolt-on type. Upon further inspection, the passenger hub assembly was clearly newer. At this point I figured the previous owner replaced the hub with a newer type model. Not sure if changing things like this (and who knows, maybe other things related have been replaced as well) would cause possibly a recalibration when new things are added within the ABS system? Not sure if that's just a reach or what.

Needless to say, I have an OBDlink MX(Bluetooth) on its way from Amazon, due tomorrow. I'm excited for this Forscan program. I've done a lot of research since you mentioned it to me and I don't think I can thank you enough for pointing me in its direction. Wow, seems like it can do everything!
 
NickyCapo said:
... But, I noticed that my front driver side was the standard clip-on (2002) but my front passenger was the bolt-on type. Upon further inspection, the passenger hub assembly was clearly newer. At this point I figured the previous owner replaced the hub with a newer type model. Not sure if changing things like this (and who knows, maybe other things related have been replaced as well) would cause possibly a recalibration ...
Click to expand...

No, no recalibration needed for new sensors or hub assemblies (or tires). All correct assemblies/sensors will give the same number of pulses per wheel revolution. If not, there would be no way to calibrate around that problem.
 
You didn't happen to clear the codes with a scan tool? I did that and my advancetrak light was flashing, had to do the recalibration with Forscan.
 
Zr0 said:
You didn't happen to clear the codes with a scan tool? I did that and my advancetrak light was flashing, had to do the recalibration with Forscan.
Click to expand...

just clearing the OBDII codes will not cause this. I've done it several times. You would have to clear the ABS calibration data or start the calibration procedure and not complete it.
 
I did clear all codes on Advanced Autos code reader/scanner. The reason I asked earlier about calibration is because of a post made on the forscan forums. Upon cross checking it, I see that you were actually the one who posted about it (and was successful) at getting the blinking light to go off. I went out to my car today and the AdvanceTrac light is still blinking, but also the ABS light has come back on? Any of these things sound familiar with the issues you had, Zr0? Guess I won't be able to diagnose properly, or possibly fix, until tomorrow afternoon when my OBDLink MX comes in.
 
NickyCapo said:
I did clear all codes on Advanced Autos code reader/scanner. The reason I asked earlier about calibration is because of a post made on the forscan forums. Upon cross checking it, I see that you were actually the one who posted about it (and was successful) at getting the blinking light to go off. I went out to my car today and the AdvanceTrac light is still blinking, but also the ABS light has come back on? Any of these things sound familiar with the issues you had, Zr0? Guess I won't be able to diagnose properly, or possibly fix, until tomorrow afternoon when my OBDLink MX comes in.
Click to expand...
Yeah that s me in that thread. If you did clear the steering angle calibration the free version of Forscan will fix it. Your abs light however I dunno I did not have that problem.
 
Hmm. I'm wondering if it's possible that after installing the new sensors that it satisfies the abs module temporarily but has been triggered back on because it's something more, such as the wheel hub like you said earlier, joegr. Is that possible? I'm hoping forscan can locate the exact problem for me. Just curious if it's the wheel hub why the dealership told me it was the just front LH wheel speed sensor..
 
joegr said:
just clearing the OBDII codes will not cause this. I've done it several times. You would have to clear the ABS calibration data or start the calibration procedure and not complete it.
Click to expand...

Hate to disagree with you Joe, but it can and does. Perhaps a difference in scanners or gen 1/2? I cleared the dtc's and that's exactly what happened. Started the car shortly after unplugging the scanner and light was instantly flashing, reread the codes and c1280 was present.

Here take a look, particularly the 5th post in: FORScan forum • View topic - Clearing DTCs Problem
 
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My scan tool only clears DTCs when I select for it to clear DTCs. Clearing other data is another selection. Perhaps yours is unable to make that distinction. If this were true of most scan tools, imagine all the posts that would be on this board about people having AdvanceTrac problems after clearing problem codes, something that folks on here seem to do all the time.
 
joegr said:
My scan tool only clears DTCs when I select for it to clear DTCs. Clearing other data is another selection. Perhaps yours is unable to make that distinction. If this were true of most scan tools, imagine all the posts that would be on this board about people having AdvanceTrac problems after clearing problem codes, something that folks on here seem to do all the time.
Click to expand...
Very possible, I don't exactly have tons of experience with scanners. And yeah it doesn't seem to be too common of a issue, that's why I threw that question in :)

That said FORSCAN did fix it, and it was with an ancient laptop, a cheap bluetooth OBDII adapter and the free version of FORSCAN. Took less than five minutes.
 
Received my OBDLink MX (bluetooth) adapter and 'plugable' brand bluetooth USB adapter for my laptop today. Everything was plug-n-play. Took a minute to get everything hooked up and paired but wasn't hard at all.

Got it to connect to Forscan. Man Forscan is f'in cool.
Setup my dashboard on there with all 4 wheel sensors, YAW, and steering angle sensor. Didn't really know what I was looking for except to see all 4 sensors reacting, which they were, as well as the others showing at least some function. Cleared the ABS codes (C1233, C1234) and then ran the calibration tests. YAW Rate/Lateral Acceleration calibration went through first time, no problems. Brake Booster/Stearing Angle Sensor calibration errored out on me the first time for some reason. Ran it again, zero issues. Blinking (AdvanceTrac) light is off. Closed Forscan and re-opened and re-connected to my LS. Set up the dashboard on Forscan again for the sensors and such. Everything looks great on my drive up and down my road.
Hope that was somewhat descriptive enough in case someone else has a similar problem.

I don't want problems to arise on my LS, but if they do, I'm pretty excited about this OBDLink and Forscan.
joegr - thanks for initially pointing me in Forscan's direction, much appreciated.
Zr0 - thanks for chiming in on here, and thanks for your Forscan forum post which I had put on the top of my bookmarks list.

All is right again...for now, anyways.
 
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Awesome, glad to hear you got it fixed Nicky. That flashing light is annoying isn't it?! Did the ABS light turn off as well?

FORSCAN is a pretty neat tool to have in the arsenal, especially pricewise.

And I know you're somewhat new around here, but don't ever discount Joe's advice. The man is a veritable unclimbable mountain of knowledge, LS and otherwise. It's pure luck I managed to guess a correct answer before he figured it out ;)
 
Zr0 - The ABS light went back off on itself yesterday after it had come back on. Very strange. But, weirdly enough, it was present today when I went out to the car with my obd adapter and laptop. And yes, after clearing the DTC's as well as doing l the calibrations with Forscan, the ABS light is off, and has been since. That blinking AdvanceTrac light is super annoying! Really glad everything turned out okay. I did quite a bit of driving around this afternoon and everything has been fine with the LS.
Joegr seems like the man around here, that's for sure. Everytime I've searched online and clicked a link that has led me to this forum, I've seen him in the thread. Thanks for pointing me in the right direction! Saved me some $ and stress.
 
Little update;
ABS light came back on. Connected back to Forscan and set up my dashboard with all 4 sensors. ABS module is throwing code C1234. At a dead stop, all the sensors are reading 0.00, except for my FR speed sensor(C1234). Its values are jumping all around, usually single digits. When I am driving, all the values on the speed sensors are of equal value. Pulled wheel and checked connections, all is well. Joegr, what do you think? Wheel hub assembly maybe?
 
If there's noise in the signal when stopped, then it's probably either a wiring problem, a sensor problem, or an ABS module problem.

Unplug the sensor while stopped. Does the reading settle down to zero? Take a paper clip or something and short out the two pins in the car's harness to the sensor. Does that settle it down? If yes to either, then it's probably the sensor. If not, you need to check the wiring all the way back to the ABS module.
 
2005_LS_V8 said:
Thanks for the clarification, joe! Maybe I'm feeling the throttle drop, but I swear it feels like the brake is on or the car perhaps is in a low gear, because as soon as I take my foot off the gas, it slows quickly.

Now I know my next step, get the codes!
Click to expand...
 
I have an 03 LS with the V8 motor which has the harsh shift from first to second gear. I would like to know more about how to get the firmware update for the PCM that is suppose to correct this problem. Is this covered under warranty for anyone that needs it, or will it cost me? Can I take the PCM out and just send it somewhere to be fixed?

I just bought the car 2 months ago, and have gone through replacing all the plugs and coils, new valve cover gaskets with sp plug seals, cleaned the MAF sensor, replaced air filter. None of that made any difference in correcting the harsh slamming into 2nd gear shifting at all. Then I bought a shift kit from Superior, polished and cleaned all the valve bores and installed new parts from the kit, changed the trans filter, adjusted the bands, and even installed the new servo fix that has the o-rings installed to stop any fluid leakage.......none of this has helped at all. I would like to get this problem solved! Thanks
 
It's not a firmware update. It's a physical repair. FETs in the PCM sometimes go bad.
Your LS is long out of warranty.
 
Ok, looks like SIA is the place to send it from what I've read. Has anyone used forscan to reprogram their PCM? It might be that my PCM was never updated, because there were a lot of problems with the LS's shifting harsh in 03 and up which did require the PCM to be re-programed in order to solve the problem.
 
Do you didn't replace the automatic transmission solenoid pack while you were down there?
 
Yes I did replace the solenoid pack with a brand new one, not one of those reman ones on ebay. It did not change a thing. I'm not sure if I can do anything with forscan, even if I was able to reprogram the PCM, what values would I use to replace the old programming?
 
Does anyone know if Forscan support is still active? I need that version 2.3.5 Forscan test build since I accidentally cleared the IVD Parameters and have the flashing AdvanceTrac light on my dash like some of you did. Maybe there's someone here that still has it and could email it to me? I'd like to stop that flashing today.
 
Yes, Forscan is still very much active. Go to their forum.
 
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