True about the lamp, that would be a good fix in the end. But I'm not sure we should look at the BCM yet. Since it does detect on the D+ that the alternator doesn't run and puts on the warning light, and puts out a steady 9.5V leads me to believe the pin is working like it should. Btw the DMM was put in current mode and connected the right way. I just tested it with a small battery and it doesn't conduct, my other DMM does conduct so I guess it also has a problem. But one at a time
.
Hey Koalar, I think it behaves a bit differently on this type of alternator. I don't know what the BCM does when the D+-pin stays above 4.5V (open circuit) but I do see it will put on the battery charging warning light after a minute or so of running without seeing D+ rise to 12+V. Putting 12V on there will not influence the output of the alternator. From the moment it's running the field coil off its own power it will output the B+ voltage to D+ as well. So you will get 14V at the D+ pin (give or take) so putting 12V on it doesn't do anything since the potential is lower on that end.
Yes indeed it's an old style 'dumb' alternator. The only thing the BCM does is raise the idle rpm in case the D+ signal stays low, puts on the battery charging light when that doesn't help after a few moments...
Thanks, I don't know if I have such a lamp but a 120ohm resistor should do just fine too then.
www.beaconsandlightbars.co.uk
www.autoelectricsupplies.co.uk
Thanks for the alert Jack. I'm enjoying reading this but really can't think of anything to add - you seem to have thought of some stuff that didn't occur to me - but I'm not strong on more modern electrics - Very happy to work with the likes of the old ACR alternators though. my new Scala has "smart" charging and does "clever" stuff like regenerative charging. All controlled via electronic control modules so I would guess it'll flag up trouble codes if malfunctioning. All getting beyond me now though, she'll be going to AVW if anything like this goes wrong. I think there's stuff which can only be done when the main factory computer is linked, through the garage computer, with the vehicle. The time would seem to have arrived when I'm admitting that Becky and my old horticultural machines and, from time to time, an old British motorcycle are probably enough for me.
Apart form the fact that the alternator has been ruled out as the problem, very few, if any suppliers will accept a part like an alternator back after it has been fitted.
Agreed. Non of the factors - or other sources of parts - that I know of around here will take back parts like this once the packaging has been opened. I notice a lot of packaging now has security seals - the last couple of brake disc sets I've bought have had seals like this on them. Not had to return any yet but I did wonder if they'd take them back with the seal broken? Surely they would if they were wrong and you'd not fitted them? (ie. in unmarked condition.) A few times in the past I've had to accept something like an air filter where the box has obviously been opened with one or two dirty finger marks on it - but containing a nice clean filter inside - Not often though, and if the factor had not been a good friend and it was the only one he had on the shelf and it was obviously in as new condition, I'd probably have refused it. However it's not a good way to be conducting business.
Having said that I've noticed that the Scala - Bluey as my granddaughter has named her - has developed a slight brake squeal from the O/S/R brake when braking very lightly. Doesn't do it when braking normally, just when very lightly braking in slow moving traffic. Of course the pads will have been assembled "dry" at the factory and, with so few miles on her it may well be them just bedding in, but if it continues I'll be whipping the caliper off, glaze busting the pads and reassembling with a little ceramic anti-seize. I'm not so decrepit I can't manage simple stuff like that yet although I must admit I'm finding it harder to lift stuff like the modern big wheels into place on the hub and get a bolt started in it's hole! You may remember I mentioned that I took a wheel off to try it for fit in the spare wheel well and found it already partly seized to the hub? - electrolytic corrosion between the wheel (ally) and hub (steel) - I need to take all the wheels off, clean the mating faces up and refit with some anti-seize which I could do at the same time I'm cleaning up the pads.
I can relate to a lot of the content above. To assist locating wheels on my Ducato, I raided my plumbing suppliea and made up a long "U" shapped assembly. The sides were 15mm stainless steel tube, the end (handle) 15mm copper, and two 15mm brass elbows glued and set screwed to the stainless steel completed the assembly. I later considered long bolts with heads removed for our Saab, which has M12 studs. When researching long bolts I discovered wheel mounting aids on Ebay. Examples here.
