I'm about ready to throw in the towel on this one. I get paid tomorrow, I need my truck running, I'm ready to just throw money at the problem.
Who's got a solution for the 89 1227747 ECU that is plug and play into a USB port and can ship overnight?
Printable View
I'm about ready to throw in the towel on this one. I get paid tomorrow, I need my truck running, I'm ready to just throw money at the problem.
Who's got a solution for the 89 1227747 ECU that is plug and play into a USB port and can ship overnight?
Six Shooter, I owe you beer!
I've already got an order laid in for a better cable, but when I read the above, a lightbulb went off.
Got my test harness (two wires to go into the ALDL, one which bridges RX and TX on the Arduino FT232 board) and plugged it in (not into the ECM) while I tested the unit in Tunerpro 4 and 5...
Cable is now "Found and Functional". R&R of the harness reproduces and resolves the problem. Apparently the cable test tests the onboard components all the way to the far side pin header and wants to see loopback on the pin header.
I'm going back out to my truck to see if some combo of futzing with things will get me talking to the ECM. Hope to have good news soon.
I was just able to successfully pull data from the truck whilst it was running!
I'm ashamed to admit that it took me all of a week to get this to happen. At the same time I'm proud to admit that it took me all of a week to get this to happen.
Apparently the TXD and RXD pins must be bridged for successful test of the unit, without it being plugged into the vehicle(as has been said, plugging the unit into the vehicle will not be a successful test).
I did so, tried the FT232 unit. Worked fine. I have another unit, an FT232RL, here- tried it too, it too passed once I bridged RX to TX. This more or less proves the test process wants loopback on the chip TXD/RXD circuit. (Kinda like testing a T1 smartjack, or a POTS jack ;) )
Went to the truck, connected the FT232 unit to the harness in the vehicle. No joy. I couldn't get data with the TX and RX bridged to the ALDL "E" pin (89 S10 Blazer 7747 BTW). Tried in WinALDL and was able to get partial, though useless, data- I couldn't even get TPS volt or anything else useful. Don't care, I'm moving toward Tunerpro and ALDLdroid for my solutions.
Tried the "RXD and TXD bridged with a diode and a 1Kohm resistor) trick. No joy.
Resigned myself to spending $100+ to get a cable and a BT module overnighted (which while a good deal for it, really need to be buying tires)
On a lark, but the FT232 in.. using the resistor and diode network, no joy. Just for S&Gs, I tried the "hardwire bridged TX and RX". Looked good, I clicked "connect"..... and got an endless "connecting" indication, but never a rejection.....
OK, interesting.... I recall hearing something about signal reflection and the TX not being needed on the 160-baud ECMs anyway... so I disconnected the TX side of the bridge.... and the damned thing CONNECTED!
BS, says I... something is fooling me. I pulled up the dash, and darn if I wasn't getting full range data.
I'm also seeing something REALLY odd. My injectors are registering 170% duty cycle. I'll move that part to another thread.....
Hey i know this is an old thread but id like to fit an ob2 male connector to a ftdi 6 pin ft232rl usb cable the pins on my car are this pin 5 is ground pin 9 is braud ? And pin 16 is 12v australian gmh holden vy commodore they run the aldl system but with a ob2 connector plug what can i expect from doing this any help on what i need to do to diy my own cable what could i expect a cable like this to do any help Cheers
Pins 4 & 5 are ground. Pin 9 is data. No 10K resistor is needed. Yes pin 16 is 12v if needed.
You will only be able to scan your VY Commodore. Use TunerPro RT and the .adx definition for the VY Commodore.
you have it.
http://www.ebay.com.au/itm/Serial-Co...QAAOSwV-RXEil8 Any thoughts on this one
That one is USB to RS485. You need USB to Serial 232 TTL such as this from the same seller. You also want an FTDI chipset in case you need to use it on 8192 baud. http://www.ebay.com.au/itm/1Pcs-6Pin...item4653b56a1f
Hope this helps,
Brian
[QUOTE=sturgillbd;61931]That one is USB to RS485. You need USB to Serial 232 TTL such as this from the same seller. You also want an FTDI chipset in c
Basically what you do is tie the RX and TX pins together and that is the serial data wire. The other pin you use is ground. Read some of the posts at the beginning of this thread. They describe what needs to be done. RS485 is a different form of serial communications. IIRC, it uses differential wiring for noise immunity. I know it seems strange to connect RX and TX together but the ecm only responds when data is requested on the 8192 baud systems. Tunerpro requests data and the ecm them responds.
[QUOTE=89S10_Project;61942]Dude.
No offense, but.. breathe. Calm down, and punctuate.e
[QUOTE=old8s;61962]OK. I see there's an app for your anbroid phone and it will run tunerpro aldldroid . I would like to use the bluetooth fl232rl module but no one has done this
http://www.ebay.com.au/itm/FTDI-FT232RL-USB-to-TTL-Serial-Converter-Adapter-5V-and-3-3V-For-Arduino-GO-/371474451179?hash=item567d9a4aeb:g:tdkAAOSw5VFWMM3 1 i also have http://www.ebay.com.au/itm/FTDI-FT232RL-USB-to-Adapter-Module-USB-TO-TTL-RS232-Arduino-6Pin-Cable-/191732706593?hash=item2ca428ed21:g:bM4AAOSwo0JWPH4 b plus this vy commodore any ideas