Brian Kirby Posted December 24, 2020 Author Share Posted December 24, 2020 Robinhood - 2020-12-24 4:32 PM Brian, I went and tried again after my last post, and the display appeared. Whilst it is far from conclusive (and I'm going to have to do a bit more testing) I'm not convinced that it hasn't got something to do with the "wake-up" I've already referred to. It certainly appears that, if I enter the 'van, quickly insert the key, and turn to "Mar", the display fails to appear. On the other hand, if I enter the 'van, sit in the driver's seat, wait for the date/time etc. display on the dash (that appears when you open the door) to disappear, then turn the key to "Mar", it does appear. A bit more testing to do on that, I think, and it's a bit cold for that here tonight, but I am going to check it out later. Thanks again Bob. That is interesting. I'll give that a go over the next day or so. I agree - apart from being dark now, the temperature has gone into free-fall here too! Thanks again. Link to comment Share on other sites More sharing options...
onecal Posted December 24, 2020 Share Posted December 24, 2020 Yes there is a delay on opening the door to instrument panel, giving the driver has to get into the drivers seat before placing key in the ignition this slight time delay is negated. The other built in delay when turning on the ignition (mar), is the two readings it takes for a reading differential of the sensor to actually give a reading. regards B Link to comment Share on other sites More sharing options...
Deneb Posted December 24, 2020 Share Posted December 24, 2020 onecal - 2020-12-24 4:54 PM Yes there is a delay on opening the door to instrument panel, giving the driver has to get into the drivers seat before placing key in the ignition this slight time delay is negated. The other built in delay when turning on the ignition (mar), is the two readings it takes for a reading differential of the sensor to actually give a reading. regards B As evidenced by the figures stated in the eLearn diagram you posted, the reading delay is little more than a second. A comparatively greater delay, although still only measured in seconds, is the run-up time of the engine ECU, which on ignition contact transfers a copy of the stored settings from the last engine stop event back to main memory and then carries out diagnostic checks before being in a fully ready state. The time this takes doesn't appear to be stated anywhere that I can find, but the reverse operation following the engine being stopped is documented as typically taking between 2 and 7 seconds, which is why it is recommended to allow the instrument cluster self checks to complete before attempting to start the engine. The oil level sensor and check display both communicate with the engine ECU, not directly, so again the waking time of the engine ECU is likely to be relevant, particularly as Fiat mention the importance of this wait period in the document concerning general failure lamp activation due to spurious oil sensor readings. Link to comment Share on other sites More sharing options...
onecal Posted December 24, 2020 Share Posted December 24, 2020 Yes but this should not create a problem it is a very short delay ???? If one fails to wait for a full boot up It should work the second time around (turning off) and after waiting for full boot up, on turning on the oil level should now show if all is OK regards B Link to comment Share on other sites More sharing options...
Brian Kirby Posted December 25, 2020 Author Share Posted December 25, 2020 Robinhood - 2020-12-24 4:32 PM........................It certainly appears that, if I enter the 'van, quickly insert the key, and turn to "Mar", the display fails to appear. On the other hand, if I enter the 'van, sit in the driver's seat, wait for the date/time etc. display on the dash (that appears when you open the door) to disappear, then turn the key to "Mar", it does appear. Tried that. Door closed, sat in seat, and waited until the cab roof lights extinguished (which on mine are the last item to disappear) and still no dash oil level indication. Good idea, though. Thanks for the tip. The problem with the above light only arose when parked nose up on our drive. Parked elsewhere (which being the year it has been, wasn't that often) it didn't appear. The "recalibration" seems to have fixed that, but now, instead of the light coming on, the oil level indication disappears, and only reappears when parked elsewhere. We live in a residential part of town, away from the centre, so I don't think the cause is likely to be external interference. The only cause that seems to make sense, in either the case of the light or that of the oil level indication, is our slightly sloping drive. I'll try going on a drive-about over the next few days (weather and tier 4 permitting) and stop in a variety of places at a variety of angles, and see what follows! Thanks again. Link to comment Share on other sites More sharing options...
Brian Kirby Posted April 24, 2021 Author Share Posted April 24, 2021 So, I think my mystery is solved! :-) It has taken quite a lot longer than I expected to be able to take the van to the right place to test the dashboard oil level gauge, but what I then discovered is this. If the van is parked on level ground the dashboard oil level indication works as described in the Ducato manual. However, if the van is parked on sloping ground, whether nose up or nose down, the dashboard oil level indication does not appear. In both conditions the General Failure lamp (with which I was having trouble) extinguishes normally. What seems to have triggered the original fault is that when the van was serviced in late 2019 the sump was over-filled. Due to Covid restrictions it had very little use after that service, but the first trip on which it was driven was the first time I saw the General Failure warning stay on instead of extinguishing with the other dash lights after the ignition was turned on. (The earlier posts to this string more or less chart the sequence.) The electronic oil level sensor was recalibrated in late 2020 after I'd reported the fault at MoT time, since when the General Failure warning lamp have behaved normally, but the oil level gauge became intermittent. So, earlier this week I got over to a downland car park with a good slope and good manoeuvring space to experiment. The result, as above, was quite clear. The gauge only shows when on reasonably level ground. It seems the General Failure light was initially being triggered because of the over-filled sump, especially when parked up-slope. The oil level sensor in the sump is in effect a resistance wire immersed in the sump oil, and is sited near the rear wall of the sump. With the sensor in that off-centre position it "sees" a higher than actual oil level when the van is parked facing uphill, and lower when facing downhill. Coupled with a slightly over full sump, the slope (on our drive) was insufficiently severe to cancel the oil level gauge (at its originally calibrated settings), so it seems the sensor was receiving an oil level signal combination outside its expected range (an abnormal combination it couldn't "understand") triggering the General Failure signal. It seems the subsequent recalibration increased slope sensitivity (so the gauge no longer appears when nose up on the drive) and also increased tolerance of higher oil levels (so what it now sees is within the expected range), and the General Failure lamp now extinguishes normally. Just in case this may help someone else who is seeing similar problems and is wondering why. :-D Link to comment Share on other sites More sharing options...
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