I see where some members are discussing a China made Tech 2 for around $500 shipped. What are the most common uses of the Tech 2? I am interested but am not sure I would use it enough to justify cost, probably because I don't really know what all that can be done with it. Post up what you have used it for.

 

I seriously doubt there is any way to follow the diagnostic procedures in the factory service manual without a Tech2 or equivalent: it can read out internal voltages and switch/relay states that would be near-impossible to access in real time while cables are connected and critical systems actually operating. Think of it as a software breakout box for (almost) every cable in the car. An appropriate analogy would be like trying to develop software without a debugger.
That said. once you get close to the $500 mark, I think I'd back away from the handheld scanners and consider one of the software-based units that use a laptop as its user interface.
http://www.autoenginuity.com/products/scan-tool.html

 

http://www.aliexpress.com/item/GM-TE...891987335.html. Good price

 

It's a good price, assuming the customs fees he mentions waaaay down at the bottom of the page don't eat up the difference...

 

I would like to program my fuel cutoff speed to a higher speed, just in case. I assume you can do that with the tech 2. I've heard it is used when changing brake fluid, not sure how, maybe someone could explain

 

First post here. I have a repair shop specializing in Cadillac and Corvette. Honestly, more Cadillac than Vette but still a healthy serving of Vettes. If you have factory service info there are some surprising simple diagnostic routines for some issues. Evaporative emissions issues that set the check engine light come to mind.

There is also the access to sensor data that with the right knowledge and experience or guidance can lead you to a concrete diagnosis. You can access some of that sensor data with an Aftermarket tool. But, to access all of it in every module you need the Tech2. The genuine Tech2 displays information very fast and navigates through the cars systems quite fast. I cannot speak for clones as I have not used one.

Also, you can actuate certain items like the motor that drives your AC temperature door. These "bi-directional" controls allow to quickly test circuit integrity and component function. If it works when scan tool says the circuit is good and the part is good and your problem must be on the control side.

Someone mentioned brakes. There are hydraulic circuits in your ABS module that are not always exposed to the rest of the system. If you change your fluid you will need a tool to actuated the valves and the ABS pump to purge all the fluid. If you ever get air in the ABS unit you will need the Tech2 or a capable tool to actuate those valves and free the trapped air. Or it will eventually migrate out into the rest of the system. Sometimes when a technician short cuts the bleed process because the pedal "feels good" the car returns in a few days with a soft pedal and must be bled again this time with the scan tool assisting bleeding the ABS unit.

I have always been frustrated when I have participated in these types of forums in the past. Someone will ask for help and I know that if the car were in my shop I could have it diagnosed and estimated in 15 minutes but the person asking for help has none of the tools I have at my disposal. If you were to have one. The pros that visit forums like this would have a much easier time walking you through to a solid diagnosis.

There is also programming and module updating. Unfortunately, the clones have a lot of issues in this area. When connected to TIS2Web (GMs programming site) many clones freeze up, permanently. Almost all fail to program. I'd be scared to try it. If a module programming event fails there is a chance the module "bricks". It doesn't program correctly it may no longer communicate and therefore not be able to be programmed correctly. It is then about as useful to your car as a brick.

I think as a DIY tool you might be better off getting something like drewtech's mongoose pro GM2 cable. The Cable is around $500 and is compatible with Tech2Win, a PCbased Tech2 emulator. You have to pay for Tech2Win whenever you use it. But, it does everything the Tech2 does for C5s and with it you can program confidently if need be. Say you need to replace your PCM or your tune is acting up you could program the PCM back to factory yourself. Either that or try to steal a used Tech2 on eBay. They often sell for under $1000.

 

Also, you cannot move the fuel cutoff speed with the Tech2. Unless you do it by reprogramming the PCM with a file that has had the value changed. I am not familiar with that process. The easiest method would be with tuner software like HPTuners.

 

The Tech2 can only be used for diagnostic purposes or to flash modules with stock GM calibrations or change options. I like the misfire graphic that can be displayed. It helped track down a cracked spark plug to a specific cylinder when the only code was a P0300.

You can use the tech 2 to do things like add or remove the TPMS or RTD options among other things.

Any modifications would need to be done through something like HPTuners.

 

Wow, great info. Helps me decide that I may not need one of these knock off tech 2 scanners. Saved me $500.

 

The one thing the TechII can do that almost no other scanner does is program key FOBS to the car, after 2007/2008 GM took out the functionality to program a fob yourself through the dash.

 

If you need to ask what a Tech 2 is for, then you don't need one. But if and when the day comes that you or a friend needs one, and have to rely on a GM dealer, you will completely understand why some forum members decided to get their own (myself included). It's actually already payed for itself with the diagnostics I've performed in the short time I've had it.

For some members, it's a paperweight (per 8Vette7) and not worth much. I think it is the single most valuable tool that a do-it-youself C5 owner could ever have.

 

It has definitely paid for itself on my end, not for the C5 as much as the Quadrasteer pickup truck which even the dealers seem to be dumbfounded by.

 

For some members, it's a paperweight (per 8Vette7) and not worth much. I think it is the single most valuable tool that a do-it-youself C5 owner could ever have.[/QUOTE]

Thats why I was asking. I had a hypertech that I used on my C4 to adjust the speedo for wheel/tire size and to set my fans to come on at a lower temp. It would also allow you to change shift settings on the auto trans. Nothing critical. I'm not saying it is not worth having, just wanted to know what some of the more common uses were. How is it the single most valuable tool, what would be the must have uses. Also, what are the risks of doing permanent damage with a knockoff version. I have only had my C5 for 5 months now, and have already done quit a bit of do-it-yourself service and some minor mods, have not needed the tech 2 for any of the things I have done, just trying to be prepared.