Vauxhall Vectra (1997) ecu communication

Sirs

I have been trying to communicate with my Vauxhall Vectra (X18XE
engine with Simtec 56.5 ECU) using my PC and a "Jeff Noxon"
interface. I have searched everywhere for some hints or
information on this vehicle and have found absolutely nothing. I have
studied and tried ODB2, KWP2000, 10400 baud, handshake bytes etc. -
all to no avail. So, experiment I did.

Wake-up was the first hurdle. I tried sending every character from
0x00 to 0xFF at 5 baud 8/N/1 and looked for a response at 10400 baud.
I got a response only from 0xE0 but could make no sense of the
characters I was receiving. After examining the bit pattern I changed
the baud rate to 4800 and received back 0x55 0x52 0x80 which looked
sensible, although not understood.

What then to send back to the ECU? After a delay of 25mS, I tried
every character and checked for a response. 0x7F worked and the ECU
then continuously sent out
90569797 0696 0696 3897 013 3 which looked like it might be some sort
of identification together with date codes (the car was built in late
1997). I responded with 0x7F again and received
0x06 0xF0 0x55 0x10 0x32 0x10 0x01 0x9D which again looked
intelligible.

0x06 - 6 bytes to follow
0xF0 0x55 0x10 0x32 0x10 0x01 - the 6 bytes
0x9D - a checksum (equal to sum of all the other bytes)

I am now in the position of many other opendiag members in trying to
work out the meaning of these codes as they are unrecognisable as
KWP2000 codes. Is 0xF0 the "tester" address and 0x55 the ECU address?
What does 0x10 0x32 0x10 0x01 mean? What do I respond with?

Sequence so far (PC set to 4800 baud)
PC 0xE0 (at 5 baud using bit-bang method)
ECU 0x55 0x52 0x80 (this is repeated once more if I don't respond)
PC 0x7F (after 25mS)
ECU 90569797 0696 0696 3897 013 3
PC 0x7F (after 25mS)
ECU 0x06 0xF0 0x55 0x10 0x32 0x10 0x01 0x9D
?

If I don't make the PC respond after 25mS then the ECU continues to
output its data continuously.

Regards

Ian McFarlane

 
Received on Fri Oct 10 14:19:51 2003