Technical DPF Light

[t1tmt]

Can anyone please explain how the DPF warning lights should operate?

My MJ120 which I took for a run from South Wales to Kidderminster a couple days ago threw an engine failure light about 10-15 miles up the road with a dip in power which lasted about 10 minutes before returning to normal but with the light staying on. MPG dipped noticeably while going up the M50 which I put down to a regeneration. Next morning when we went to West Midland Safari Park the Engine Light was on but had gone off when I restarted the car to go around the Safari route (4 miles in 1st and 2nd gear) Coming home yesterday the Engine Light was on again with Torque Pro showing P2002 (Particulate Efficiency below threshold). Im waiting for the rain to stop so I can take the laptop out to put MES on to see the DPF Clogging etc but in the 4 months I have owned the Doblo I have never seen the DPF light come on except during self tests. Any thoughts of anything else worth checking.

Also, does anyone know if its possible to check clogging levels over obd2 without using MES as I would consider building some kind of monitoring display to fit in the car using Arduino or Raspberry Pi. However if the level is not possible to get over OBD2 then its not worth further investigation.

Thanks in advance
Tom

 

[Poperon]

Hi,

I can't help much with the warning lights and error code, only to say that when I had similar problem a seized solenoid on the EGR valve seemed to be the problem.

However, I do like the idea of a DPF clogging level on an Arduino driven display.

After a few minutes Googling I found a few examples of how to connect up this sort of thing and there are Arduino libraries to help out with reading the OBD2 data.

No mention of DPF clogging though, I suppose the question you are asking is whether the MES "clogging level" is included in the OBD2 data or is it a figure derived by MES (from the DPF pressure difference etc).

Who would know?

Cheers

Ron

 

[t1tmt]

Thanks ron, I have actually made some progress with the raspberry pi/arduino plan, need to get a screen to use though. I was thinking its probably a calculation from the Dpf pressure readings. If I make any progress for this I will let you know.

 

[Poperon]

Hi Tom,

A bit more Googling.

If the plan is just to see the DPF clogging level only (not any other parameters) then would it be an idea to connect the output from Differential Pressure Sensor direct to the Arduino rig?

Doblos may be different but I found a paper which says "A relatively clean DPF will return a voltage of approximately 0.5V. This rises to approximately 4.5V
for a full DPF"

Cheers

Ron

PS I mention Arduino a lot (not Raspberry Pi) as I no nothing of Raspberry Pi but have played around with Arduino a bit.