What can Techstream do that others cannot?

Techstream is the official Toyota software, which you use with Toyota/Scion vehicle’s. I think it is the most comprehensive because of this. The interface you purchase to connect to the vehicle can cost as little as $20 (Chinese clone) and up to $2150 (current MSRP) for the CarDaq M.

 

Code:

https://www.amazon.com/obdator-Reader-Scanner-Engine-Diagnostic/dp/B074V5YBYR/ref=sr_1_8?ie=UTF8&qid=1536354242&sr=8-8&keywords=usb+elm327

$12 with Prime shipping...

 

Add another key fob

 

LasVegasaurusRex, I’ve only had Techstream, and none of the others, for Toyota at least, so I’ll have to cede to others to explain the differences.

 

$12 that one is, but it also doesn't say J2534 anywhere in the listing, so that would make it an example of a reader that will not work with Techstream. I notice the listing also says "(Not support Hybrid or electric vehicles)".

To answer the original question, there are about two dozen computers in your car. The generic code readers are usually good for reading generic diagnostic info from about three of them. So, one thing Techstream does is it saves you from being that guy who comes and posts on PriusChat someday when your car has a problem, saying "I've got these warning lights on the dash but my Acme CodeBoy Pro tells me there aren't any trouble codes at all so that means the car is just crazy right?" (and then five or six people jump on and say yeah, look how your 12 volt battery's at 11.9 so the computers are probably totally making stuff up, and a week later your thread's at 50 posts and your car still has the same problem that nobody's identified yet). Just kidding, that never happens here.

Now, the stuff you can do with a diagnostic tool goes beyond just reading trouble codes when the car throws them. You can also read lots of actual data on how the car is operating, and that can be a great help when you are trying to track down a problem.

Some of the alternative products do allow you to load Prius-specific data definitions in some way or another, and then they can also show you that stuff, at least from the subset of the car's computers they are able to talk to. Where those data definitions come from is often other people painstakingly reverse-engineering them based on the stuff they can see with Techstream, and the lists can be incomplete, and some of the entries may have errors.

Finally, in Techstream, there are a bunch of active tests, where it can command various parts of the car to do things. Headlights not working, and you're not sure if it's a problem with a switch or a fuse or the lights? Go into Techstream and tell it to turn them on; if that works, you know they're ok and the trouble might be in the switch stalk. Those active tests are things that can really save you time and scraped knuckles if you're trying to solve a problem. (Saves you scraped knuckles because back in the days before you could do that, you used to have to dig down to the right wiring connections buried under other stuff and poke at them with your electrical tester.)

Those kind of active tests are often not nearly as well supported on the alternative products, even if somebody has reverse-engineered a lot of the data-reading functions for them. That's probably because a lot of people are comfortable trial-and-erroring around with data-read requests on their cars' comm networks, but sort of draw the line at blindly sending half-understood commands to the computers in their cars to find out what they'll do.

So if you just want to be able to do necessary diagnosis and work on your car without having to add a sideline in computer protocol geekery to your list of hobbies just to be able to do it, Techstream is the thing.

-Chap

 

Yes, but I haven't found one that didn't work yet. They all mostly use the same counterfeit ELM chip inside. It is more effort to redesign the silicon or schematics to not support something than to just steal like for like. It may not say it supports it, but it almost certainly does inside. Maybe the software they sell with it doesn't support it. But again since all the chips are the same, flashing a competitors firmware and using TS should work.

It looks identical to one of the the ones I have that works just a different brand on it.

 

Just to make sure I understand ... you're saying you have used one of these ELM-knockoff, non-J2534 dongles with Techstream, or you haven't quite exactly done that but it "should work"?

If you have, what did it show up as in the Techstream "VIM select" menu? What was the name of the J2534 DLL that you used with it, and where did that come from?

Thanks,
-Chap

 

I have used an ELM knockoff that wasn't listed as being compatible. But the insides are the same thing. I've bought like 100+ of these things over the years. I just buy the cheapest crap on eBay or Amazon and give most of them away to people that need a reader. I have never changed my Techstream install from years ago or used multiple apps on the phone for the bluetooth ones.

 

Here are the three VIM Select options set up in Techstream on this laptop:

I don't actually own a "TIS Techstream VIM" (made by Denso), though I'm told it works really well. But the driver DLL for it is there, in case I ever win one in a raffle.

I do own an OpenPort 2.0 (bought directly from Tactrix, not counterfeit), and an "XHorse" MVCI (not really from XHorse of course, as the counterfeiters made their original business unsustainable AIUI.) Both of those work (the OpenPort more so than the MVCI)—but only when the matching driver is selected. I can't go plugging one in, and selecting a different one in VIM Select, and expect it to work.

You can see they have slightly different sets of capabilities, and the driver function libraries come in different DLL files (ComTol32.dll for the Denso one, op20pt32.dll for the OpenPort, and MVCI32.dll for the MVCI knockoff).

So, what driver are you using with the $12 ELM dongle you posted about?

-Chap

 

Just in case anyone stumbles into this thread looking for it, another VIM, officially supported by Toyota, is the Drew Technologies MongoosePro MFC2, for which the J2534 function library is called MongooseProMFC2.dll.

 

XHorse. It is the only one I use. It just works with everything on my system. Perhaps I've been incredibly lucky, but I literally have bought over 100 of these things just by buying the absolute cheapest.



PriusChat keeps chopping the resolution. So here is the full resolution image: http://image-host.us/images/KVwiJAaVgx/techstreamxhorse___xsAhcq9wIf.jpg

 

Something I do that most don't though is I actually run it through a VM as shown. So technically it always the VMWare USB driver that acts as a negotiating host within the XP sandbox.

 

Which is kind of funny, when you think that Drew Technologies was (as I understand it) involved in writing the J2534 standard, which wants the DLL file names to be no longer than 8.3....

-Chap

 

The 8.3 limit was removed from the October 2015 revision of J2534-1. You still have a good point, though: the file name is still supposed to end in “32,” which Drew Tech’s doesn’t:

8.1 Naming of Files

Each vendor will provide a different name implementation of the API DLL and a number of these implementations could simultaneously reside on the same PC. No vendor shall name its implementation “J2534.DLL”. All implementations shall have the string “32” suffixed to end of the name of the API DLL to indicate 32-bit. For example, if the company name is “Vendor X” the name could be VENDRX32.DLL. The programming application can determine the name of the appropriate vendor’s DLL using the WIN32 Registry mechanism described in this section.
​

You know this already, but since others may not: the “Registry mechanism” requires the available devices and their DLLs to be described in subkeys of HKEY_LOCAL_MACHINE\Software\PassThruSupport.xx.yy, where xx and yy are the major and minor version numbers of the J2534 API.