PhilA Posted May 21, 2018 Share Posted May 21, 2018 Fair enough re vibration/data loss etc. Nice little scope, got me a Tek 100MHz analog storage scope which works well, but picked up a HP logic analyzer off eBay recently that's a fantastic boon for digital work. Phil rob88h 1 Link to comment Share on other sites More sharing options...
Fabergé Greggs Posted May 21, 2018 Share Posted May 21, 2018 Scope chat! I use a Picoscope 2204 now, such a handy tool. Link to comment Share on other sites More sharing options...
Zelandeth Posted May 21, 2018 Author Share Posted May 21, 2018 Some of the stuff you can do with a decent logic analyser (especially if you know how to drive it) is amazing. Likewise is how capable a lot of the modern digital storage scopes are. Mate of mine has a Rigol 1074Z (I think, may have the model number wrong) and the stuff that thing could do seemed - to someone like me who's grown up with old school scopes - like total witchcraft. Especially when you got into stuff like real-time data packet decoding and math operations. All in one little, totally portable box. Hoping that in a few years time they'll start to trickle down to the third or fourth hand market at prices I can justify. Some of the PC based ones are actually pretty decent now too - though I'd always be wary of them being left behind by the rate that desktop PCs seem to move on at these days. ...says the guy who has machines still running Windows 3.0, 3.11 and 2000... GrumpiusMaximus 1 Link to comment Share on other sites More sharing options...
Zelandeth Posted May 22, 2018 Author Share Posted May 22, 2018 Unsurprisingly after 22 years, the low oil level light on my Xantia is somewhat prone to false triggering - especially on warm days. What really surprised me though is how many cars *still* don't have this facility fitted. They'll tell you if your washer fluid is low, your AdBlue, your headlight washer fluid etc...but no mention of engine oil aside from the pressure light...and when that comes on (especially in a modern car!) it's most likely already too late. I'll stick with the handful of unscheduled oil checks when the light pings up on startup thanks...it gets checked every week or two anyway. Suffice to say today's episode was indeed the second time this year it's happened, and she hadn't actually used a drop of oil since the last change. rob88h and Tadhg Tiogar 2 Link to comment Share on other sites More sharing options...
Tadhg Tiogar Posted May 22, 2018 Share Posted May 22, 2018 Unsurprisingly after 22 years, the low oil level light on my Xantia is somewhat prone to false triggering - especially on warm days.IMG_20180522_194513.jpgWhat really surprised me though is how many cars *still* don't have this facility fitted. They'll tell you if your washer fluid is low, your AdBlue, your headlight washer fluid etc...but no mention of engine oil aside from the pressure light...and when that comes on (especially in a modern car!) it's most likely already too late.....One of the little things about the CX that fascinated me was the little oil level gauge on the right of the instrument pod which springs to life for 15 seconds after turning the key before going back to sleep. I call it the electric dipstick and so far it's been pretty accurate. rob88h 1 Link to comment Share on other sites More sharing options...
Zelandeth Posted May 23, 2018 Author Share Posted May 23, 2018 One of the little things about the CX that fascinated me was the little oil level gauge on the right of the instrument pod which springs to life for 15 seconds after turning the key before going back to sleep. I call it the electric dipstick and so far it's been pretty accurate.Renault are the only non-PSA manufacturer that I can think of off the top of my head who routinely had a level gauge in their models. Not sure how far back, but my 25 had one, as did a mate's 21 and the 19TD at work... Wonder if they work on the same principle at the Xantia (and therefore I assume CX) ones. No floats - it uses a heater that's partly submerged in the oil and tracks how rapidly it heats up, then uses that data to work out the level. That's why this one (likewise on my previous TD) only tended to throw the odd false warning generally only in warm weather I think. It struggles with accuracy a bit when the oil temperature is already quite warm. The oil temperature seems far more affected by the ambient temperature than the coolant temperature is. GrumpiusMaximus and rob88h 2 Link to comment Share on other sites More sharing options...
PhilA Posted May 23, 2018 Share Posted May 23, 2018 All my modem vehicles have a level sensor; they do not employ a gauge but will give a written warning. My truck displays "ENGINE OIL LOW. ADD OIL", along with a pressure gauge. The ECU knows about all burned bulbs but refuses to give insight into items such as a burned headlight or brake light though. Win some lose some. Phil Link to comment Share on other sites More sharing options...
GrumpiusMaximus Posted May 23, 2018 Share Posted May 23, 2018 Mine tells me about low oil before it gets critical. It is, however, sensitive to oil so finding the right stuff just after the light has flashed up is a pain. Last time it happened (about six months ago) I just went and bought a bottle of the closest stuff I could find and it only needed a small top-up. I've changed it all since then anyway. The number of people that don't know how to check their oil is what really alarms me. Link to comment Share on other sites More sharing options...
Saabnut Posted May 23, 2018 Share Posted May 23, 2018 My Bentley (and the Rover P4s) utilise the fuel gauge. Press a button on the dash and the fuel gauge becomes an oil level gauge. Surprisingly accurate too. PhilA, Squire_Dawson and rob88h 3 Link to comment Share on other sites More sharing options...
Zelandeth Posted May 23, 2018 Author Share Posted May 23, 2018 My Bentley (and the Rover P4s) utilise the fuel gauge. Press a button on the dash and the fuel gauge becomes an oil level gauge. Surprisingly accurate too.Had forgotten that on the Rolls/Bentley having the little oil level marker on the fuel gauge. Granted it's a long time since I was last in one. Don't think I've ever been in a Rover P4... The old Renault one used to switch to serving as an oil temperature gauge once the engine started didn't they? Usually having a separate backlit scale for the level that went out once the engine started. rob88h 1 Link to comment Share on other sites More sharing options...
PhilA Posted May 23, 2018 Share Posted May 23, 2018 On cars like the 21 and 25 and 19 I have seen it. My GTA has the same dash but it's fitted with fuel, temp and volts gauges. Personally I would have preferred an oil pressure gauge... Phil Link to comment Share on other sites More sharing options...
Broadsword Posted May 23, 2018 Share Posted May 23, 2018 One of the little things about the CX that fascinated me was the little oil level gauge on the right of the instrument pod which springs to life for 15 seconds after turning the key before going back to sleep. I call it the electric dipstick and so far it's been pretty accurate. Unsurprisingly after 22 years, the low oil level light on my Xantia is somewhat prone to false triggering - especially on warm days. What really surprised me though is how many cars *still* don't have this facility fitted. They'll tell you if your washer fluid is low, your AdBlue, your headlight washer fluid etc...but no mention of engine oil aside from the pressure light...and when that comes on (especially in a modern car!) it's most likely already too late. I'll stick with the handful of unscheduled oil checks when the light pings up on startup thanks...it gets checked every week or two anyway. Suffice to say today's episode was indeed the second time this year it's happened, and she hadn't actually used a drop of oil since the last change. On my Xantia HDI the oil level light flashes for a short while after startup. I'm assuming it is a false alarm since the car is running brilliantly and oil level is spot on with no oil consumption at all. binhoker668 1 Link to comment Share on other sites More sharing options...
Zelandeth Posted May 23, 2018 Author Share Posted May 23, 2018 On my Xantia HDI the oil level light flashes for a short while after startup. I'm assuming it is a false alarm since the car is running brilliantly and oil level is spot on with no oil consumption at all.Yep, if it flashes for 30 seconds or so on startup it's reporting low oil level. Seem to recall dead sensors not being unknown...seem to recall it's a pain to get at, so probably not worth faffing with, especially if you're diligent about regular checks. Broadsword and rob88h 2 Link to comment Share on other sites More sharing options...
Zelandeth Posted May 25, 2018 Author Share Posted May 25, 2018 Nothing really to report car wise...though I've got myself a little project for the weekend. If this blasted headache subsides at some point anyway. Three days solid now and counting - it's getting old. Especially as I've not slept in that time for more than about ten minutes a time. Important lesson if you've got a bunch of old computer stuff like me. If putting things into long term storage, make sure anything with batteries that might leak have had them removed or replaced beforehand... I totally forgot that the Acorn A3000 even had one, and this was what I found when dismantling mine to investigate why it wouldn't boot when dug out of the loft. Well that's going to be "fun" to repair! Doesn't look quite so spectacular now I've cleaned it. All those inductors test fine on the meter, though the mouse port is a bit of an unknown quantity at this point. I do have a scrap machine I can nick that from if needed though. There are a few tracks on the board that will need to be repaired though. Fingers crossed the internal layer is intact (it's a three layer board) or it'll probably be scrap. ...not likely to be replaced either given what these machines seem to change hands for these days unfortunately. Really want to get it fixed though as this was the first computer that was ever really mine. mat_the_cat and rob88h 2 Link to comment Share on other sites More sharing options...
PhilA Posted May 26, 2018 Share Posted May 26, 2018 Had a bit of that on the expansion card in my Compaq. 4.5v so it now sports a rechargeable battery pack from an old cordless phone. At last count it was unplugged for 6 months and the time was still correct when I booted it up... I was having a think about electrolytic capacitors though, and probably the ones in my ECU need replacing, really. Most of them are just input voltage rail smoothing. Phil Link to comment Share on other sites More sharing options...
406V6 Posted May 27, 2018 Share Posted May 27, 2018 My 406 has an oil level display which shows the level when the ignition is switched on. It uses the mileage display to do this. rob88h 1 Link to comment Share on other sites More sharing options...
Zelandeth Posted May 28, 2018 Author Share Posted May 28, 2018 Firstly investigated why the Invacar was grumpy last time I ran it. This would do it. All jets cleaned out and the 1/4" of sludge cleaned out of the float bowl. It's not getting run from that fuel tank again. Also gave the Activa's seats a going over with the leather balm. Definitely helped. rob88h, DeeJay and Broadsword 3 Link to comment Share on other sites More sharing options...
Zelandeth Posted May 30, 2018 Author Share Posted May 30, 2018 Few things done today... First up, the new ECU for the Lada turned up. Quick check showed we did in fact have life on the check engine light output as intended - so I set about finishing up the wiring to the light on the dash. Now, my original plan had been to use the position on the dash originally for the seatbelt light...as it's not sharing any feeds with the brake warning lights etc (which the original check engine light does). The previous version of this module I took apart had individual coloured filters for each light in it, so it was expected to be a quick matter to pop the cover off and swap the little square bits of plastic around. Cue much surprise when I popped the cover off and was presented with this. What the heck Lada? Production changes?!? Also...why is there a bit of Bristol VR in my Lada... Okay...no shuffling lights around then...I just found another warning lampholder with spade terminals that I was able to shove into the original space and connect separately. It's messy but does the job, and makes it infinitely easier to reverse if required in the future. Resulting article... Now the sight of a check engine light usually fills people with dread...but in this case no. Because even if it doesn't go out properly, it shows me that I now have a working on board diagnostic system...so I'm no longer trying to fault find while blindfolded. Especially given how fantastic the documentation for this system is. While I had the dash in bits, I decided to investigate the indicators. The dash indicator has always blinked once when the ignition was turned on, and tended to go mad if you turned the headlights on. It was in some way interacting with the dash lighting, but I never figured out how or why. It never actually affected operation of the indicators - but after an hour long drive of it blinking madly at you it gets...wearing. I did note that the flasher unit wasn't the type I expected to see...but I had a "proper" Lada one in the bag of random spares...so figured it was worth a shot. Here's the two units...small one is the one I just pulled off the car, the larger cased one is a "normal" Lada flasher unit. Unsurprisingly swapping this out sorted out the ridiculous indicator behaviour. It also has resulted in the indicator tick actually being loud enough to hear above 10mph. Useful given they don't self cancel. I still find the design of the dash light for the indicators highly pleasing on this dash...is one of my earliest memories of the one my grandparents had when I was about three - and probably started the interest! So...started the engine up. Check engine light goes out...stays out for about five minutes...then lights up again right as the car tries to drop into closed loop mode. Two codes logged. 13 - No oxygen sensor signal. 35 - Idle speed fault. The oxygen sensor fault isn't entirely surprising given the fault with the previous ECU had been shoving a continual 1.5V across it. Annoying though as it's only a few months old...only £25 from eBay for a genuine Bosch one though, so not the end of the world. ...Even though I will need to drop the damn downpipe to change it. You can't get a wrench into it in situ because it's too close to the steering box. As for the idle speed fault...no idea. I've not had that one before, so will need to refer to the documentation on that one. Cleaning the idle air control valve and checking the throttle position sensor will be the starting point I think. Oh...and the obligatory vacuum leak check. So one step forward and...0.3 steps backwards. Happier now as I've an actual fault to chase down rather than a vague "it's not running right" which was all I had before! mat_the_cat, DeeJay, Shep Shepherd and 6 others 9 Link to comment Share on other sites More sharing options...
Zelandeth Posted June 1, 2018 Author Share Posted June 1, 2018 Have I mentioned lately that I hate the tree by our driveway? Poor car. rob88h 1 Link to comment Share on other sites More sharing options...
Tadhg Tiogar Posted June 1, 2018 Share Posted June 1, 2018 Have I mentioned lately that I hate the tree by our driveway?IMG_20180601_132717.jpgPoor car.Unfortunately all trees do this. Councils do spend a lot of money pollarding them, but the bastards keep growing new branches and leaves. Can sort of see why Sheffield City Council got into hot water for daring to cut down their trees.... Link to comment Share on other sites More sharing options...
PhilA Posted June 2, 2018 Share Posted June 2, 2018 I would be very surprised if the Check Engine light is driven directly from an IC. Most of the heavy duty type outputs on mine are open collector, with a discrete (albeit surface mount) transistor to drive the item. Unless that's an LED in the holder? Anyway, cue the regular lame jokes- check engine? Yes, it's still there... Phil Link to comment Share on other sites More sharing options...
Zelandeth Posted June 2, 2018 Author Share Posted June 2, 2018 I would be very surprised if the Check Engine light is driven directly from an IC.Most of the heavy duty type outputs on mine are open collector, with a discrete (albeit surface mount) transistor to drive the item.Unless that's an LED in the holder?Anyway, cue the regular lame jokes- check engine? Yes, it's still there...PhilIt's driven by what appears to be a FET if my reverse engineering is correct - the issue is that the control signal from one of the ICs which should be activating it isn't...and I've totally failed to find any data on the IC in question. Further investigation has shown that particular ECU to have several issues though - the inability to interrogate it for diagnostic data being but one. There's no clock signal present at the Comms port for one, and shorting the relevant pin in the diagnostic socket to ground should also put the system into a set state in addition to flashing out error codes - it didn't do that either. So there's something well awry with it. I do have a new one at least now so can actually deal with the faults that are presented in a more methodical way. As for the tree... it's on private land, however due to some highly convoluted ordinance dating back to the building of the estate, we're not allowed to remove it. I'm hoping that given enough persistence that the council will actually come and take a look at it and then see sense. Especially as I've already said "I told you that was going to happen three years ago" regarding it undermining the footpath, carriageway and probably wrecking the BT duct under the footpath. Yes, I have a well saved paper trail to that effect. rob88h 1 Link to comment Share on other sites More sharing options...
mat_the_cat Posted June 2, 2018 Share Posted June 2, 2018 FET This always makes me smile, ever since I posted on another forum about when I fixed a 2kW mains inverter. I'd used it to power something which I reckon had a large inrush current, and their tiny on resistance had allowed a 'rather large' current to flow, causing them to look something like this: This is where someone pointed out an alternative name of Fire Emitting Transistor Tadhg Tiogar and LightBulbFun 2 Link to comment Share on other sites More sharing options...
Zelandeth Posted June 2, 2018 Author Share Posted June 2, 2018 This always makes me smile, ever since I posted on another forum about when I fixed a 2kW mains inverter. I'd used it to power something which I reckon had a large inrush current, and their tiny on resistance had allowed a 'rather large' current to flow, causing them to look something like this: Trophies_Solar_MPPT_Ver_2a.jpg This is where someone pointed out an alternative name of Fire Emitting Transistor Oh, that must have made quite an impressive bang! Given that a lot of my work with electronic stuff is with valve based kit, transistors are generally referred to as "three legged fuses" by me. It's astonishing how much abuse valves can take and still work quite happily. LightBulbFun 1 Link to comment Share on other sites More sharing options...
PhilA Posted June 2, 2018 Share Posted June 2, 2018 Transistors don't crack around their base and gas up though. Phil Link to comment Share on other sites More sharing options...
Zelandeth Posted June 2, 2018 Author Share Posted June 2, 2018 Transistors don't crack around their base and gas up though.PhilTrue enough, though having restored a few dozen radios over the years and a handful of TVs, I've replaced probably half a dozen valves in total. Probably half of those due to having been physically broken before I got the sets in question. Lord knows how many semiconductor devices I've swapped. Granted... transistor based stuff tends to be less prone to giving you an almighty belt when you find something you didn't realise was tied to the HT rail with the back of your hand. Valves don't have the tin whisker growth issues that affect some earlier transistors (AF117?) either...that fault has taken me on a merry old dance on a couple of occasions - especially one which had it but intermittently. GrumpiusMaximus 1 Link to comment Share on other sites More sharing options...
PhilA Posted June 2, 2018 Share Posted June 2, 2018 I've had a few things with tin whiskers. Valves don't tend to go noisy either, but also remember that the stuff you're repairing likely was bleeding edge semiconductor whilst the tube kit was rather mature. Shame a new ECU was found, you could have had a Back To The Future style contraption mounted to the hood of the Lada. Link to comment Share on other sites More sharing options...
Zelandeth Posted June 2, 2018 Author Share Posted June 2, 2018 Oh don't count it out, I've not got it running properly yet! I do intend to do more of a detailed post mortem on the original ECU once I've got it up and running properly as I'll have some known good values to compare to then. If time permits anyway. I get the impression that there's going to be a point somewhere over the next couple.of weeks where the activity level here is going to go bananas. When that happens I'll need to be careful to retain some degree of focus rather than madly darting from project to project every five minutes. rob88h 1 Link to comment Share on other sites More sharing options...
somewhatfoolish Posted June 2, 2018 Share Posted June 2, 2018 This always makes me smile, ever since I posted on another forum about when I fixed a 2kW mains inverter. I'd used it to power something which I reckon had a large inrush current, and their tiny on resistance had allowed a 'rather large' current to flow, causing them to look something like this: Trophies_Solar_MPPT_Ver_2a.jpg This is where someone pointed out an alternative name of Fire Emitting Transistor Reminds me of a college project I was involved with, converting a pedestrian trolley to electric drive; none of us had a clue about current limiting so we just added extra MOSFETs to the power stage until the smoke stayed inside. We burned through about £200 worth of BUZ11s to get there. I did teach myself a bit about PWM though, which was close to witchcraft to me at the time. rob88h, GrumpiusMaximus and mat_the_cat 3 Link to comment Share on other sites More sharing options...
Zelandeth Posted June 2, 2018 Author Share Posted June 2, 2018 Speaking of PWM and multiplexing... Why on earth can't they run the systems in modern cars at a high enough frequency that the blasted flicker isn't visible? It drives me spare in the vast majority of modern cars. I really can't see any reason for it aside from lazy design... Link to comment Share on other sites More sharing options...
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