T42 Bench Flash Tool - 120 ohm Termination

[dave w]

I'm wanting to build a stand alone T42 Bench Flash Tool, without using an E38 computer for the 120 ohm CAN termination.

I'm needing help findig a T42 Bench Flash Tool schematic that shows the 120 ohm Termination resistor.

That attached .pdf shows a T42 / E38 Bench flash tool. The Tool I would like to build will not have the E38, so I'd like to use 120 ohm resistors instead.

Thanks in advance,
dave w

[NISANDA]

i can read t42 with out the e38 ECM they just dont show any vin number or vehicle info etc, but the file its readeble and writteable.

[dave w]

i can read t42 with out the e38 ECM they just dont show any vin number or vehicle info etc, but the file its readeble and writteable.

That good to know.

Would you be willing to share the wiring diagram of your T42 bench tool?

dave w

[NISANDA]

That good to know.

Would you be willing to share the wiring diagram of your T42 bench tool?

dave w

Yes, the pins are:
Pin 31 - Ign Voltage (Switch)
Pin 32 - Battery Voltage (Constant)
Pin 49 - Ground (Big Black-white wire)
Pin 37 - CAN -
Pin 38 - CAN +

Works very good read all v8,v6 and 4 cil ecotec transmisions no problem.
And it does read with Vin and vehicle info with tunercats.

[dave w]

Thanks for the information:thumbsup:

I ended up wiring like the EFI Live Tutorial, including to the ECM. See Pic below.

dave w

13993

[In-Tech]

Semi subject and a bit off topic. Do any of you know where to buy connectors and terminals for e38, e67 and t42 at a reasonable price? I haven't set up bench programmers for any of the above and would like to. Thanks,
-Carl

[In-Tech]

https://www.speartech.com/Benchtop_Programming_Harness_s/1824.htm
https://obd2allinone.com/products/m5con.asp

These are a couple places I have found and I just can't see spending that much money since I know the connectors/terminals can't be that expensive. I have no problem with people making a nice product and making some money, it's just a tough gig when I can do it myself.

[NISANDA]

Thanks for the information:thumbsup:

I ended up wiring like the EFI Live Tutorial, including to the ECM. See Pic below.

dave w

13993

Yes pretty much the same 

[dave w]

Semi subject and a bit off topic. Do any of you know where to buy connectors and terminals for e38, e67 and t42 at a reasonable price? I haven't set up bench programmers for any of the above and would like to. Thanks,
-Carl

If you already have the Molex part #'s Mouser has them: https://www.mouser.com/

dave w

[dave w]

Yes pretty much the same 

Pin 11 (Ignition Switched) is listed on the EFI Live Tutorial.

dave w

[In-Tech]

Hi Dave,
Thanks for the reply. I'll research the molex part numbers. I was hoping someone had a cheat sheet already. I haven't used my power and signal account(or whatever they are called now) in a while. Thanks for the mouser tip. I have found in the past that some of the suppliers like them are sometimes cheaper due to the volume they buy.

edit, I'll know better which connectors I need when I learn the pinouts needed for bench programming. Do you have the molex part number for the t42 connector and terminals and if the terminals are all the same for the connectors for the e67, e38 and e40?
Thanks again,
-Carl

[In-Tech]

I found the black 73 pin molex, e38 and e67, $9.80. 1 at a time through my power and signal account, still gotta find terminals and seals and the other connectors. I'll keep digging, anyone that wants anything I find can have it at cost, plus shipping obviously. And of course would be on this original order only, probably a couple weeks away.

[In-Tech]

John at TunerCat said I could pass this along as well. It's the pinouts for all the CAN based controllers if you want to make your own bench top programming station. :thumbsup:

[In-Tech]

Hi Dave, and others,
All of my older flash programming stuff, mefi, lt1, 0411 etc just had the basics and have served me well. Basics meaning, 12v, 12v switched, ground, comm, can't remember the rest if anything. Now that I am putting together some of the new stuff(e38, e40, e67, t42) I am building an enclosure that will have the 12v and 12v switched on toggles with LED's and am going to add a check engine light as well as fuel pump light. I believe both circuits just ground the pin to turn the led on. Do those last two connections need a resistor to load?
Basically each ecm/tcm harness adaptor will have a 10 pin 1/4 turn connector and the enclosure will be used for all of them with its' own 10 pin 1/4 turn. Can you guys think of anything else I should add? I'm just talking for basic programming and not an ecm test bench(that will come later, I've only been working on that for years lol).

[NISANDA]

i run kind of the same setup for bench read-writte, but only have check eng light, the obd2 port and the switch as led build in (ON on the ON position).

[In-Tech]

Here's a couple pics of a BS one I made for a pos aftermarket tbi company so I could test their crap on the bench before I tested it on a real vehicle. I used my function generator for rpm, the other two knobs were TPS and MAP, The LED's were watching main power, switched power and injectors.
The other pics are where distributor machines go to die. lmao Obviously a pressure chamber in the mix too. :)

[In-Tech]

Seems like a lot of dust and rust. Kinda like me :D

[In-Tech]

I went a different route for my bench top stuff so I won't be ordering from power and signal. I'm just posting an update in case anyone was waiting on a group buy or anything. I found this guy on ebay.
https://www.ebay.com/itm/264256482159?ViewItem=&vxp=mtr&item=264256482159
Super nice and helpful. I got e38, e40, e67 and t42 from him. They arrived and have all the leads so I can add things at a later date.