Oldstreetracer said:
Thanks all, I just purchased a new scan tool that reads ABS codes (it's rated very highly on Amazon), you are correct my older one does not. I was told in a different forum that this failure could not be read on a scan tool and that the dealership has to test each sensor input that relates to the failure instead. Shame on me, I Should have to to this forum first for my Avy. I will post the scan tool findings
Thank you
Ability to read codes and scanning sensors/monitoring systems are two completely different things and are highly dependent on both the vehicle and scanner involved.
First the scanner has to establish communications with the vehicle computer. There are 4 or 5 different protocols used by different manufacturer's/vehicles for communication with the vehicle computer through the same OBD2 connector. 2006+ are mostly standardized on CAN protocol.
Ability to read basic OBD2 powertrain codes and display a handful of basic OBD2 powertrain values/sensors is standardized. This is the "compatibility with all OBD2" that the scanner manufacturers like to quote. Just because a scanner claims to be compatible with all OBD2 from 1996 up to present, that doesn't mean you will necessarily be able to get what you want or be able to do what you want on a particular vehicle.
Each car manufacturer has developed the OBD2 system to monitor many other things. Like manufacturer specific powertrain items, ABS, SIR, and the entire myriad of things controlled by the BodyControlModule (BCM) and specific function modules such as the TransferCaseModule (TCM), and anything else on the vehicle system bus. Because enhanced functions are not standardized.... in order to access any of this enhanced funtionality a scanner needs to know what to send to the specific vehicle computer to get the desired response back - furthermore, then it needs to know how to interpret what it gets back.
So the information the scanner needs to know to perform enhanced functions on a 1996 Blazer is not necessarily the same for a 2010 Avalanche, or a 2006 Ford, and so forth. All of this enhanced info is controlled by the manufacturer who developed it and they will charge a scanner company for that info. then the cost is passed on to you. Some scanners allow you to buy enhanced GM PIDs or Ford or Chrysler as an add-on. Others expect you to buy a set for a specific year and make. This set of enhanced PIDs will not be exhaustive, but will include a significant number of PIDs and hopefully the one you need will work on your vehicle. There are also software apps that have reverse engineered a lot of the PID info, but sometimes the same enhanced PIDs doesn't work for all models within a manufacturer.
So the top of the line is the GM Tech 2 scanner - it does it all.
Then comes the high end scanners like Snap-on and the high end Windows software like Autoenginuity. These can do most things if you buy the option.
Below that is the software Tuners use to modify the software for their vehicle computer like EFI Live and HP Tuners. These provide some bidirectional communication functionality with the vehicle PCM, such as crank sensor relearn and injector balance tests and transmission control. Also a lot (but not all) of enhanced functions for the powertrain that I have tried on my GM vehicles. As I understand it they do ABS and SIR PIDs but no experience there. I do have VCM Scanner myself at $350.
Below that is ScanXL Pro with GM enhanced PIDS at about $150. I also have it, but don't have much use for it anymore. It does a lot like VCM scanner does, but without the bidirectional communication functions.
The best deals I know of are specific smartphone apps that use the BAFX Bluetooth OBD2 adapter as found on Amazon for $22.
Torque Pro - good for many enhanced GM powertrain PIDs - slick look - easy to use. Does not do ABS, etc $5.00
Dash Command - same company as ScanXL Pro. Good for many enhanced GM powertrain PIDs - slick look - easy to use. Also offers iPhone version to use with a Wifi OBD2 adapter. Does not do ABS, etc $10 + $10 per vehicle for enhanced PIDs.
Car Gauge Pro - in my experience reads all codes for all systems including BCM, SIR, ABS, etc. Does not support enhanced PIDs for GM CAN protocol vehicles (really was made for Ford/Nissan). Reads tons of PIDs for Powertrain, but both system modules and PIDs are completely unfiltered except by manufacturer. You have to experiment and see what works with your specific vehicle. Difficult to use interface, and its a try and see what works software. With Car Gauge Pro I have even read ABS wheel speeds on my 2008 Ford (GM ABS won't work), watched fuel tank pressure on my 2004 Avalanche during the EVAP testing sequence. Also read BCM codes for HVAC on the Avalanche. Best value at $8.95 if you have patience and understand what is going on.
good luck!