Vauxhall Corsa 1.3cdti Mjd603 ECU no Comms

**obd.tech** · 13th May, 2021, 01:20 AM

Hi folks, looking for some help in trying to find the cause of this Vauxhall Corsa 2008 1.3cdti Mjd603 ECU no Comms in diagnostic.
The fault is internal of the ecu. Had the usual water ingress, but not too badly corroded after a good clean & inspect with a microscope.
Thinking it may be the can tranceiver, I swapped a known diagnostic working 1 from a scrap but semi working ECU.
Thinking it may be a software corruption, I fgtech bdm flashed all 3 flash/mpc & eeprom files over too. Software said successful. Still zero Comms with opcom or MPPS V18 on the bench.

A couple of questions for the helpful knowledgeable guys with Marelli MJD603 on here please

1. Do you have to replace the bdm 0ohm resistor back on the PCB, this 1 got damaged, can I leave it off? What difference will it make? Can I just link the solder pads together?
2. Any ideas on the cause of the fault? What can I test? Seems like it may be an internal power failure?

I can attach some photos if needed for u guys to point out test areas?
Thanks in advance for your time :-)

**jnoroeste** · 13th May, 2021, 11:24 AM

Hi M8, check wires in ecu plug.
for resistor you only need to bridge, you can with solder point instead resistor.
Regards.

**obd.tech** · 13th May, 2021, 06:17 PM

Thanks jnoroeste, the ECU cannot be recognised on the bench (powered correctly) with either Opcom or Mpps.

Any ideas or experience of this folks?

**obd.tech** · 16th May, 2021, 12:56 PM

Just to clarify, there is no communication with the ECU via the Can communication line terminals or obd2

**volodin69** · 16th May, 2021, 10:56 PM

After water damage, from let's say ...of 10ecus i've had, almost 6-7 could be repaired... the problem can be anywhere on the pcb.
Follow the plus power pins and traces on the pcb and you will find out where the interruption is.

**obd.tech** · 21st May, 2021, 08:16 PM

Thanks volodin69, I will try that and see what I might find, is it likely to be a 5volt power regulator or does the can tranceiver work on a 12v feed?

I also have another ECU that has a P060-29 Replace ECU control unit DTC, starts fine but only revs to 1500rpm ..... Have you any ideas on that one too?