vdubois

Is anyone else running Datamaster with my setup. I keep losing connection.It will run for 5 seconds and thenlose connection. I am using a new laptop with a usb cable to scan. i can see and clear the trouble codes but i cant do anaccurat data log because of this issue. Im going to post on there site also but i figured someone on here would have my setup.

95Blackhawk

I lose connection all the time with my setup also. Still don't understand why but sent my cable back and they said there was NP with it. Unfortunately, I have fried 3 PCM's so I had to make adjustments to how I program to make sure it never happens again.

vdubois

I have done the cable tests and they al say it is good. I was playing around with the software link timing and i could make it worse but not better. I was also reading that a bad ground could cause issuses with aftermarket ignitions but i also dont think that is the problem since i am well grounded. Anyone else have any ideas.

vdubois

There has to be more people trying DataMaster. I emailed them this morning and havent gotten a response yet. My laptop doesnt have serial ports on it, could it be the usb causing the issues. It wasnt just in this program, i have also tried tunercats with the same issues.

mdenz3

I use datamaster on my 94 lt1 pcm, i built my own "two transistor" type cable and hardwired it to the ECM and never had nay connections problems. And I always make sure the battery charger is on if i'm writing a program to the ECM *IMPORTANT*

aifilaw

Where I work we use serial connections a lot, so do our customers. Since a lot of them use laptops without a serial DB-9 or DB-25 connection, they have to use a USB-Serial interface cable
about 1 out of every 3 brands we try, operates *sometimes*
25% of the time they do not operate, it is fixed by actually installing the drivers that came with it, or from that mfr. website.
the other 75% of the time, were just out of luck.

Sounds like you have the same problem...get a real serial connection, or get a different/better USB-serial interface cable and your problems will disappear

vdubois

I havent been able to keep a good enough connection to attempt to write to my pcm. Im not buying anymore of these POS cables, how/where did you get the instrucions to build you 2 transistor cable. Im guessing it is not a usb cable so i will still need a serial converter. Good thing i bought the "reccomended USB cable" that doesnt work rather than one of those cheepie cables that wouldnt work exactly the same.

I am also using the manufactuars suggested drivers.

mdenz3

kmkommes

After a long time troubleshooting I found my serial port wasn't putting out enough voltage to power the aldl cable. It was only 5V when you need 12Volts to power the cable correctly. My cable would work only 10% of the time with my laptop. I built a harness to power it from the battery f my car/truck instead of using the power from the serial port. I found this when I noticed I could always connect to my desktop pc which output 12 volts on the serial port.

vdubois

Im looking at this diagram and looking at my equpment, and the USB cable does not put out 12 volts, it only puts out 5. If i have to have 12 volts going to the ecm there is no possible way the USB will work. Can the usb cable be modifies to run 12 volts if i modify it with the resistors to look like the diagram below or is this only usable with a 9/15 pin serial.



If i take the wire that coinsides with pin F, cut it and put 12 volts to it will that power my ecm or just fry it.

vdubois

I need to check my cable when i get home, acccording to this i should be getting my 12 volts from pin 16. If im reading this right that should power my ECM without an external supply. Maybe i need to dissasemble my cable and look for a bad connection from pin 16 to wherever it is supposed to go.


http://www.aldlcable.com/sc/details.asp?item=aldlobd2

"94 and 95 cars that are equipped with the 16 pin OBD2 style connector have built in +12v power coming off of pin 16 and ground coming off of pin 5. The 8192 baud serial data comes off of pin 9 in these connectors. This +12v power arrangement allows us to build a simpler cable with no lighter plug +12v needed."

i420tom

hey guys i have had them same [edit] prob as you get bad data error and dtc codes that all should have not been there

i have a 94 z so that 12volt is not my problem.

took me a long while to figure it out and i [edit] fixed it myself!!!!

while power my laptop via the cars cig lighter i would get tonnnnnns of errors. unplug it and run on laptop battery=NO MORE ERRORS.

solution for dead laptop battery= extra car battery thrown of the floor of passenger side to supply 12 volts to my laptop cause lap bat is dead= no errors either. so my issue is electrical interferience and i have no high powered aftermarket ignition sys-yet