Yeah - by all accounts the Bosch DDE4 has a similar thing going on with gear ratios.
I know what CAN ID wheel speeds need to be sent in on, but I think I'm missing something else yet.
Most annoyingly, my test setup on the bench isn't generating wheel speeds on said ID at all yet - and I'm not totally sure why. The dash is showing various ABS/DSC faults despite none being stored in the ECU. Perplexing... but I'll get there.
At this rate I'll end up buying another E39 auto just to do a data log on it...
As Marshall says the feeds are triggered on pos1 - the hevac then when it comes on drives the transistors to the operate the fans at the desired speed. Unless they're short at least :)
That's handy you can get the controller so readily - I didn't realise that.
It will most likely be the transistors on the motor controller (which is on the motor itself) that are dead short - it is fairly common. So the fuse was removed to stop it running full pelt all the time.
As for the AC - really that should have been pumped up a fair bit higher than 3.5bar to test. Aside from the top corner of the condenser being the usual failure, the suction line (big pipe) along the firewall where it is sat against the foam is another. As the pipe sweats in normal operation, the water is sucked up by the foam, which then rots out the back of the pipe causing tiny pin hole leaks in it where you can't see them.
If you've put dye in though, at least it will give you an idea of where to look - just keep an eye on it. And push the foam back away from the pipes on the firewall and see if any evidence of it appears there too.
If you check the datasheet for ez chill, it is 80-95% tetra...1,1,1,2, ie r134a.
But as I say, other cans/products don't seem to be but I've not looked into them further. Interestingly STP now do one for r1234yf too.
Natural selection is underrated.
Just so long as they don't take anyone else out with them, preferably.
If you think what I have said is me suggesting that someone does go and fill their car AC system with a nice flammable mix then great - you've taken something said out of context and twisted it to get all dramatic about it. You could also pipe antifreeze into the AC system if you tried hard enough.
The point was both of those mentioned materials (which are also referred to as refrigerants when used as such!) are easily obtainable because they are not fluorinated gases and thus anyone could, if so inclined whilst it is not advisable for safety reasons, put them into their AC system.
And that is, I'm betting, what is in a lot of the other DIY top up kits. If they say they only contain 'hydrocarbon' or 'natural' gases with no mention of HFCs... then what else is it going to be? Legitimate question - there may be something I don't know about.
For all the snowflakes out there that don't understand common sense here is the disclaimer just for you - I don't endorse putting anything other than the manufacturer's specified refrigerant and oil into your car's air conditioning system.
Anyway - my point was in post #1... people often say it is best to leave your AC on. My findings on my own compressor, that has been idle for some time, show exactly why.
Anecdotal bit of info - I've had to regas my own cars for reasons unrelated to taking it to bits or doing an engine conversion only twice: the first time a pipe rubbing through on bodywork. The second I hit a deer.
Never had one 'just run out'.
Dave - you seem to have a habit of trying to start arguments and fuel them with random snippets from google.
I don't believe in bubble wrapping anyone and everyone that can't use a bit of common sense to work out that leaking propane into your cars interior might not be a great idea. It isn't rocket science, is is it? Come on.
I'm qualified, as is Richard, I don't personally care what others do with their time so long as I don't have to fix their mess - I don't know how Halfords get away with selling it and I don't care to delve into it further. They do, its expensive, whatever.
And before anyone says 'well in that case, how does anybody sell a fridge freezer to a customer without fgas' - the end user isn't handling the refrigerant, much like they aren't when it is operating in their car. Purchasing a can or cylinder of an fgas is intent to handle it. Unless you just want to pop it on your shelf and admire it, maybe.
Aside from that, most new domestic stuff now doesn't use an fgas. R290 (propane) is widely used in commerical small scale (maybe larger I don't know) refrigeration - you'll find a lot of catering equipment uses it. R600(a) is butane - you'll find that in a lot of domestic kitchen appliances. In both situations it is far less likely to develop a leak that could cause a fire/explosion risk as in an automotive application. Neither are fluorinated, and thus anyone can handle them or even vent them to atmosphere legally.
134 vs 134a is not the point - they are both fluorinated gases and thus fall under FGas regulations.
Butane/propane mixes are not - and thus legally, anyone could wang them in. Straight dry propane can make an excellent refrigerant. Didn't say anything about it being safe, did I?
Some of the DIY things are actually R134a as it turns out - although you have to look through the MSDS datasheets to see that. A lot however are not. Probably just butane/propane mixes. As I said, there is some loophole they're working around.
Before I got my cat1 2079, the last time I had the RR filled up (back in V8 form) I went to an F1 autocentre. Got home, and while the AC was working... it was hissing - and while everyone that knows me knows I hear when things and jest about it - I damn well know when something isn't right. They knew exactly how much needed to go in, and it should not have been hissing. I knew the system wasn't leaking, because I'd already pressure tested it.
Took it back, argued with them and they did it again and gave me the machine's print out to prove how much they put into it.
What the same guy clearly didn't see is that the machine also printed out how much it recovered - 627g. Somewhat short of the 1380g factory charge.
I don't give a shit if gas is expensive if I'm paying for a flat rate service, you damn well put in what the manufacturer calls for. Would you only half fill the coolant or oil?
The RAC aren't authoritive in this matter so what they say is meaningless - along with anyone saying its normal for an automotive AC system to lose up to 20% of its charge per year... if its losing it - it is leaking. Yes flexible lines are slightly permissible to migration of the gas but it is minute.
To be fair I've not seen an automatic machine that does a pressure test - only a vacuum, which is really not good enough and that is my opinion, because a vacuum can pull small leaks closed. There may be a loophole for mobile air conditioning - I can't remember and honestly, I'm not bothered - I'm not filling anything up without a nitrogen test first. Gas costs money and is damaging to the environment.
It's also worth pointing out that the rules in other countries are very different - in the US, a gas and go even on R22 systems is the norm with known leaks. Here we can't legally fill anything that we know is leaking. So any garage with or without an automatic machine filling a mobile system with a leak knowingly is just doing so for the money.
As I said in my first post - it is not running the AC that causes the seals to dry up. And I'm not demanding anything - don't like it, don't use it - but don't be surprised when it comes to summer and it mysteriously doesn't work. I can't say I've noticed any of my cars warm the interior slower in winter because I've had it on.
As for filling from a can - there IS a loophole for things like cans of 'EZ Chill', some of which do actually contain proper refrigerant. I was surprised by that - but given how much they cost - normal punters can crack on, I'll stick to the big cylinders thanks.
Yeah - but you'll always get those that think turning the AC off will save them a tiny bit of money in fuel (usually offset nicely when it needs repairing as a result) or those that just don't think AC is ever necessary...
Well - to the latter people, that's your opinion and you can keep it, I hate being too hot.
Lack of refrigerant in the AC will only pop the book symbol on an EARLY P38 - or a late one with the incorrect HEVAC fitted.
This is because early P38s drove the AC clutch directly from the HEVAC (through the safety pressure switches). It monitored the current drawn when the clutch was engaged. No gas would open the pressure switch thus cut off the clutch - raising a fault.
Later P38s changed to driving the clutch through a relay, because driving it directly was frankly a bit of a crap idea - corrosion in connections etc would often cause it to not engage properly. When they did this, the software in the HEVAC was changed to disable this fault detection - because a relay doesn't draw much current compared to the clutch, and this would have triggered the fault otherwise.
As for the condenser fans - ignore them if they are not running while you are diagnosing - on a standard P38, they will rarely come on in the UK climate IF your viscous engine fan is operating properly. They will only come on at low speed if the high side pressure reaches 17 bar, and switch to high speed (you'll know this when you hear it) at 21 bar. With a viscous fan even free-wheeling pulling air over the whole cooling pack, this basically never happens here.
If yours is a 2001 and has the correct/original to it HEVAC, no gas will not trigger a fault for the AC - it is blissfully ignorant of the state of charge and will try to engage the clutch all day long if it wants it, but the safety switch will do the job of preventing actual operation (rightfully so, don't run it with no gas or you'll be looking for a new compressor and flushing metal debris out of the system).
A dead blower - either because of a power supply fault (very common) or actual dead motor / brushes / controller will raise a fault though. Really... as I'm sure you already know, plugging it in with a nanocom or otherwise is the best place to start.
But it wouldn't be a bad idea to check RL6/7 in the fusebox - does the spot in the box look melted at all? After that, the connections in the drivers footwell - there is a plug with two thick wires in it. White green and white purple I think. These are the positive feeds from RL6 and 7 in the fuse box to each blower. Cut them out of their connections and crimp/solder them directly together - this causes a lot of blower stop faults due to corrosion in the connectors. Its probably more likely to be those or the fusebox (or a combo of both) than an actual dead blower in my experience.
The traces in the fusebox are marginal for these feeds - when you add in extra resistance from corroded connectors, its unsurprising how often this happens.
What will NOT cause a melted fusebox however is blocked pollen filters. A blocked filter = less air flow = less worked done by the motor = less current drawn by the motor. Just think about a vacuum cleaner - when you block the hose, the motor speeds up. Why? Because its got less load on it - so it spins faster using the same or less power as its doing less work :)
This is a bit of an aside from my M57ness, but I thought I'd share it anyway in a new thread.
A nice example of why you should keep your A/C on all year round. This compressor has only sat idle for about two years - the system didn't leak at all before the car was written off.
Where the seal hasn't been kept under pressure with the gas and oil in the top discharge plate, moisture has crept in corroding the aluminium surfaces against the seal. A vacuum pulled it shut, but then the high pressure of the discharge side of the compressor has just started to blow past the corrosion.
Thankfully the surfaces on the compressor side and the seal (still nice and pliable) cleaned up okay, and the top plate from the used replacement compressor also cleaned up nicely. Now to put it back together again and wiggle it back into place.
Yeah - I have heard back from someone now so have a bit more to go on. The BeCM isn't really the issue - its not really involved in things. Its getting the relevant data into the engine ECU in a format that it likes, but without having an original donor vehicle to do some full data logging from where I can actually use the cruise control, it is difficult to know what to look for.
Still, made some progress last night - actually did my first BMW module coding too and it appears I haven't bricked my test ABS ECU which is a bonus :)
As for the AC... gas recovered, thankfully barely lost any. Replacement compressor sat waiting to be swapped in. As its another used item, I think I will get a rebuild kit for the one that comes off if it looks okay inside. I'm hoping it is just the top discharge plate seal that is the issue, but we'll see. Very hard to get a look at it while its hiding down on the underside of the engine.
To be fair, we did have at least one dat where the HEVAC was showing 38c outside and I was hooning it through the forest with the AC running and it still never came on high speed.
It is a beast of a fan. I highly doubt it will have a problem keeping the diesel cool on even hotter days.
Hooning = lots of windy roads with heavy acceleration and stop/go. Certainly wasn't just sitting at a constant speed of any sort - I was having fun.
Unfortunately... while it is still working... it isn't going to for long -_-
My compressor is leaking. So this evening I'll be recovering the gas and hopefully swapping in another compressor if I can pick one up today. I guess it might have taken some damage in the crash - it was fine before.
Work on the cruise control has been proving difficult. Supposedly someone has been able to make it work, but I haven't had any luck in contacting them for a hint of what I might be missing.
Soon I'll probably end up with the majority of an E39 laid out in the shed electronically with every conceivable sensor input being emulated.
I think this is all done now... finished off with a bracket off the front of the engine to support the suction line somewhat:
Considering its been a tad warm today and the car was almost 40c in the dash when I started it up... I'm pretty happy with this outcome.
Now to see if it keeps working...
Finally getting around to sorting the AC. Although it has been putting up a fight... parts not arriving, things going wrong... usual stuff.
I wanted to retain the V8 pipe routing, as there is very little room between my steering column shaft and turbo to route the suction line (big pipe) down to the AC compressor. Instead, my pipework runs between the front of the engine and the cooling fan. Not ideal, but tidier and its not actually really in the way of much.
I'm using Eaton's EZ clip fittings and GH001 hose. All of which are hard to come by and pretty expensive... but seem like they will do the job. Just got some bits to finish off before it goes in and I can leak check/fill it up.