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Re: Delco HDRC (Y17DT DYRX, DMRW & DNLF)

Posted: Mon Dec 22, 2014 8:34 pm
by antus
It sounds like it could be the same architecture as an ALDL delco systems. That box reads the key and sends an OK to the ecu, and the ecu waits a couple of seconds after starting for the OK message and ifs not been received at that point flag is set which disables the injectors.

Re: Delco HDRC (Y17DT DYRX, DMRW & DNLF)

Posted: Tue Dec 23, 2014 5:16 pm
by slewinson
Looks very similar to the one on the Barina. Barina immo has K line for diags in parallel with the ECU. Seems to send the OK signal to the VSS line on the ECU once power is applied. Still trying to work it out...

Simon

Re: Delco HDRC (Y17DT DYRX, DMRW & DNLF)

Posted: Wed Dec 24, 2014 6:45 am
by Ionut
Ok, you have some code from other Delco ECU that handles that information? because here i`m stucked, i don`t know what to search for.

Re: Delco HDRC (Y17DT DYRX, DMRW & DNLF)

Posted: Wed Dec 24, 2014 4:24 pm
by slewinson
I have some disassembled code from a 68HC11 ECU in this forum but have not worked out the immo code at all. I have observed it with an oscilloscope when trying to debug a VSS DTC.

Simon

Re: Delco HDRC (Y17DT DYRX, DMRW & DNLF)

Posted: Thu Dec 25, 2014 10:01 pm
by Ionut
Here did you put the osciloscpe? on K-Line?

Re: Delco HDRC (Y17DT DYRX, DMRW & DNLF)

Posted: Fri Dec 26, 2014 6:33 am
by slewinson
On the VSS line between the ECU and immo. On the barina the VSS line goes from the sensor to the immo and then from the immo to the ECU.

Simon

Re: Delco HDRC (Y17DT DYRX, DMRW & DNLF)

Posted: Fri Dec 26, 2014 10:24 am
by Ionut
Ok, on my car VSS goes from ABS unit to ECU (If VSS means same thing in my head and in yours or course :D )

Re: Delco HDRC (Y17DT DYRX, DMRW & DNLF)

Posted: Fri Dec 26, 2014 12:58 pm
by slewinson
VSS is vehicle speed signal. Do you know the pinout of the immo? Mine has a a 9 pin connector, 6 is vss in and 7 is vss out to ECU. It also has another output that can be programmed from what I can tell.

Simon

Re: Delco HDRC (Y17DT DYRX, DMRW & DNLF)

Posted: Sun Dec 28, 2014 10:16 am
by Ionut
Can be this part of IMMO?
2014-12-28_0206.png
2014-12-28_0206.png (17.29 KiB) Viewed 8827 times
This is the bhi.w branch of a more complex function.


On my car VSS goes directly to ECU. K line goes from ECU to IMMO and then to other systems that use K line

Re: Delco HDRC (Y17DT DYRX, DMRW & DNLF)

Posted: Wed Dec 31, 2014 1:58 pm
by antus
Its a bit out of context... what do you think is in d0? The response from the immo? I cant say if its right or not but you could try patching that function and see if it'll still boot and see if you can break the immo function on a working car. Then you know your looking at the right code. Or could nop out the bne to 51a86 and see if the function at 6ae86 clears the security. I recommend going options / general / dissassembly and setting number of opcode bytes to 8. Need to do it once in graph mode and once in list mode. Can then easily see the bytes in the bin. Note there is a risk of engine damage hacking the code without being sure but I would think its a reasonably small risk. However it's your decision.