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Grahamc250
Member
Also what is the range of pressure values I should be seeing when operating as it should? Thanks
Fault code advice P244A7A
- Thread starter Grahamc250
- Start date
OP
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Grahamc250
Member
One last thing I noticed which not sure if it makes a difference as when the fault code was on the section “enabling of lambda control read” NO
After I reset the fault code it then said YES for this part
Just wondered if that was anything to help with the diagnosis
After I reset the fault code it then said YES for this part
Just wondered if that was anything to help with the diagnosis
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- E55K SL500 E250X2 Smart44 Brabus Track car E450Cabriolet X350 Pick up
It will be a faulty pressure sensor. Get a genuine one. You may need the DPF cleaning afterwards and the adaption values re-set for it to work 100%.
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Grahamc250
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I got a Bosch one as I assumed a merc one would generally be a Bosch just marked up as mercs..? I did take the car out for a good 50 minute motorway drive today just to see if there was any warning light come up again but nothing at all never gone into limp mode car run beautifully . I did an entire recording on the diagnostic machine throughout journey but as your aware from reading the post I’m pretty clueless
the highest pressure reading was about 0.08bar the fill level went upto 27% was 3% when last checked. Are these values about right ? Do they suggest a pressure leak ? I’m guessing the car would have performed a regen in that amount of time driving ?
the highest pressure reading was about 0.08bar the fill level went upto 27% was 3% when last checked. Are these values about right ? Do they suggest a pressure leak ? I’m guessing the car would have performed a regen in that amount of time driving ?
Supernoodle
Active Member
There shouldn't be any need to force a regen unless with the new sensor it suddenly says DPF is blocked. From what I've seen reported here the force regen doesn't work anyway, at least on icarsoft.
I haven't got DPF on my Merc, but on the other cars I see differential pressure spiking up to about 140mbar on accels. That's with a partially loaded DPF.
I'm assuming the lambda control is one of functions that gets disabled as a reaction to the fault. When a fault is set there is a mechanism to inhibit functions that could be impacted by that failure. So for example if you have any fault related to DPF, ECU can't be sure of soot load so it would disable EGR to keep soot to a minimum to stop DPF getting plugged
I haven't got DPF on my Merc, but on the other cars I see differential pressure spiking up to about 140mbar on accels. That's with a partially loaded DPF.
I'm assuming the lambda control is one of functions that gets disabled as a reaction to the fault. When a fault is set there is a mechanism to inhibit functions that could be impacted by that failure. So for example if you have any fault related to DPF, ECU can't be sure of soot load so it would disable EGR to keep soot to a minimum to stop DPF getting plugged
HITECH
Active Member
Re-generating a DPF after replacng the DPF sensor is quite important to do because it makes sure you are starting from the cleanest possible point with the new sensor. DPF's and the sensors are extremely un-reliable. Ive repaired/replaced my fair share of them both. A non mercedes DPFE pressure sensor WILL go faulty very quickly. As long as its got Mercedes stamp on it you will be fine.
