Tech 2 Purchase

[TJ Baker]

So I could resist no longer and opened my own VCI to inspect. When first I received it the unit passed all tests. It now fails 2 sub-tests, TPU 12 & 15 and MUX 4WAL of the level shifters. These failures don't seem to have affected my use of the Tech 2 at least as far as I am aware.

No jumper wires seen in mine but I did find some rework had been done as 3 surface mount components had clearly be touched up.

 

[TJ Baker]

I guess it’s a mystery until we can see what the tool is doing when booting. I am hopeful my new VCI works differently and that I can send you the goofy one for testing. It would be interesting to see what is going on.

I'd love to have a look at the goofy one!! I don't think we would see any data traffic from it at the time of the fault though, as no Tech 2 traffic is happening at that time. What is happening is the hardware of the serial data bus is initializing. That would be best seen on a scope, a tool I have not yet acquired.

 

[George B]

I'd love to have a look at the goofy one!! I don't think we would see any data traffic from it at the time of the fault though, as no Tech 2 traffic is happening at that time. What is happening is the hardware of the serial data bus is initializing. That would be best seen on a scope, a tool I have not yet acquired.

I think my Dad has a scope… It’s vintage…

So I could resist no longer and opened my own VCI to inspect. When first I received it the unit passed all tests. It now fails 2 sub-tests, TPU 12 & 15 and MUX 4WAL of the level shifters. These failures don't seem to have affected my use of the Tech 2 at least as far as I am aware.

No jumper wires seen in mine but I did find some rework had been done as 3 surface mount components had clearly be touched up.

View attachment 303304

looks like mine. I have touchup in the same area! I am not home now but can get a pick when I get there.

 

[George B]

I wonder if we have this thread too far off track and need help from a Mod. Perhaps moving all the trouble chatter to a thread called “Tech2 Issues”. I dunno, maybe it’s ok. I just wouldn’t want to discourage anyone looking to buy one. I don’t regret my purchase. @07Burb

 

[George B]

@TJ Baker what would we look for with a scope?

 

[Fless]

So I could resist no longer and opened my own VCI to inspect. When first I received it the unit passed all tests. It now fails 2 sub-tests, TPU 12 & 15 and MUX 4WAL of the level shifters. These failures don't seem to have affected my use of the Tech 2 at least as far as I am aware.

No jumper wires seen in mine but I did find some rework had been done as 3 surface mount components had clearly be touched up.

View attachment 303304

That's some rough looking touchup!

 

[TJ Baker]

@TJ Baker what would we look for with a scope?

Well that is out of the realm of my experience!! I suppose I would observe normal traffic for a while to see what that looks like and then connect the Tech 2 and see what happens. Voltage spike maybe??

 

[TJ Baker]

......

 

[George B]

@TJ Baker
I got my new VCI Module today and tried it out. Seems to have corrected the issue with one exception. On the Envoy I still will get the gauge drop and UNKNOWN DRIVER but only when I request info from it for SPS but I don't have any stored communication DTCs after the event. I am unsure if this is normal or not.

Otherwise the tool boots and connects with no issue to the 2002 Envoy and it connects to my Candi in one try as well.

I wrote to Chinacardiags explaining the issue and correction but I am not hopeful they will respond with a refund for my replacement VCI.

 

[George B]

I gotta say I am a little shy to try updating calibrations in the envoy yet. Maybe I will try tomorrow.

 

[TJ Baker]

I gotta say I am a little shy to try updating calibrations in the envoy yet. Maybe I will try tomorrow.

I am of the mindset of if there is not a specific reason or need to update a module I will not do so.

I did update a junkyard 2003 TrailBlazer PCM ($15) on the benchtop just to become familiar with the process as well as snoop the class 2 data bus during the event for curiosity.

 

[Rocket Man]

I am of the mindset of if there is not a specific reason or need to update a module I will not do so.

I did update a junkyard 2003 TrailBlazer PCM ($15) on the benchtop just to become familiar with the process as well as snoop the class 2 data bus during the event for curiosity.

There’s always the chance you’ll brick the module, and then you get to buy another one which THEN creates the need to at least program it to your vehicle and while you’re at it, it’s good to check for updates! Don’t ask me how I know.

 

[TJ Baker]

On the Envoy I still will get the gauge drop and UNKNOWN DRIVER but only when I request info from it for SPS but I don't have any stored communication DTCs after the event. I am unsure if this is normal or not.

Well I have as you know a 2002 GMT360 and have literally used my Tech 2 hundreds of times including requesting SPS data with it and have never experienced any gauge drop or unknown driver events or anything like that.

I am still of the notion there is some hidden issue with your Envoy.

 

[TJ Baker]

There’s always the chance you’ll brick the module, and then you get to buy another one which THEN creates the need to at least program it to your vehicle and while you’re at it, it’s good to check for updates! Don’t ask me how I know.

I HAVE swapped in a junkyard PCM with my TrailBlazer, ran the security relearn and it ran fine. Did it just for the experiment and recorded the class 2 data stream while doing it for later analysis. Also then swapped back my original PCM. I can get used PCMs here for under $20 at the Upull.

 

[George B]

I am of the mindset of if there is not a specific reason or need to update a module I will not do so.

I did update a junkyard 2003 TrailBlazer PCM ($15) on the benchtop just to become familiar with the process as well as snoop the class 2 data bus during the event for curiosity.

There’s always the chance you’ll brick the module, and then you get to buy another one which THEN creates the need to at least program it to your vehicle and while you’re at it, it’s good to check for updates! Don’t ask me how I know.

Well I have as you know a 2002 GMT360 and have literally used my Tech 2 hundreds of times including requesting SPS data with it and have never experienced any gauge drop or unknown driver events or anything like that.

I am still of the notion there is some hidden issue with your Envoy.

There very well could be an issue with the Envoy. I have several calibrations with updates available but the last time I tried to update it it failed and I had to pull the battery cable to get it to start again. All was good after that. I wish I could find out for sure if its the truck or the tool.

 

[George B]

@TJ Baker I am half tempted to send this thing to you to mess with and see if it makes your GMT360 geek out. Shipping would likely be a killer.

 

[George B]

I still think it might be the tool. Here is what it does to my 13 Burb when I request info. I don’t think this is normal.

 

[TJ Baker]

I still think it might be the tool. Here is what it does to my 13 Burb when I request info. I don’t think this is normal.

So before seeing this video I had thought you only had this type of error on the Envoy.

That sure looks like something is bad with the tool.

For comparisons sake tomorrow I will make and post a short video of my Tech 2 and TrailBlazer requesting SPS data. For the 2002 TrailBlazer/Envoy I can even show and explain each instruction the Tech 2 sends and the data it receives!!

 

[George B]

So before seeing this video I had thought you only had this type of error on the Envoy.

That sure looks like something is bad with the tool.

For comparisons sake tomorrow I will make and post a short video of my Tech 2 and TrailBlazer requesting SPS data. For the 2002 TrailBlazer/Envoy I can even show and explain each instruction the Tech 2 sends and the data it receives!!

I decided to try pulling the info to see if it acted weird. Sure enough.

 

[3JFamily]

I'm thinking of buying this Vident scanner for my 2006 Suburban:

Vident iLink 400 GM Code Reader ABS SRS SAS Scanner ( Pre-downloaded software ) | eBay

We pre- downloaded the software and item works out of the box. The manufacturer is continuing updating the software to cover the latest vehicles. It has not only the basic functions such as reading/erasing codes and live data, but also advanced functions including actuation, adaptation and...

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Am I going to be able to read live feed ac functions?