7 replies to this topic

[kingcreaky]

OK, got a 97 rover MPI mini, Broke down the other night on the M1 on my way back home. The problem was the alternator was bust and not giving a charge. I purchased a new alternator, and fitted it. The only problem is, I forgot to note down which terminals the wires went to on the old alternator, so now. When the engine is running the terminals on the back of the alternator show 14v when the engine isnt running they show 12, so from this I can assume my brand new alternator is working. However, I must have it wired up wrong as the battery is still discharging when driving it.

I have included some piccies, I wandered if somebody out there with an MPI could have a quick squize at where the cables go to on their alternator in comparison to how ive wired mine to tell me if its correct or not?

http://www.creak-it....or/DSCF2429.JPG
http://www.creak-it....or/DSCF2430.JPG
http://www.creak-it....or/DSCF2431.JPG
http://www.creak-it....or/DSCF2432.JPG

Hope somebody can help me!!! Hope everyone has a great xmas

thanks for reading

[Bounce]

You quite possibly need a new battery. If a battery has been discharged a few times it lose's it capacitence (ability to hold a charge) and needs to be re-conditioned and load tested.

If you buy a new battery that should solve your problems, as the alternator is working fine (due to the 14v when engine is running).

[Wiggy]

Here you go dude.

 STA40089_sized.JPG   64.72K   13 downloads

Glad you asked actually. Because upon lifting my bonnet I realised that my Oil Cap wasn't on properly. So it's melted to buggery on the exhaust manifold, and I have oil everywhere. Just choice!

[miniboo]

well according to that pic you dio have it wired wrong king creaky. best sort it quick before you do any permananet damage

[Bounce]

Either/or. It doesnt matter. Both terminals do you same thing. You have two output terminals just incase your running a massive ICE system (or such like) and need the extra Ampage. Running two power lines halfs the load on the one wire setup, reducing the risk of the insulation breaking down due to heat.

Youll notice on earlier minis to the MPI that they have to power lines coming from the alternator.


That setup up will be fine, just get a new battery

[kingcreaky]

I have purchased a new battery. Still no luck (you will notice that the setup WIGGY kindly posted) the alternator has two terminals and not three like mine!),

putting the voltmeter directly on the battery it reads 12v, when you start then engine is reads 11.8 11.7 etc, when you rev the engine up it still reads the same 11.7 etc. On our other minis this is 12v until you start the engine, then it reads 14v !! therefore I conclude something is wrong.

OK, Please see the attached.

Terminal 1 - Big Fat Cable - This goes to the solonoid (the terminal in which the battery live connects), so you could assume this is the return cable, or charge cable. this cable measures a constant 12v, except when then the engine is running then it bumps up to 14v. The alternator terminal this is still connected to is labelled (B+)

Terminal 2 - Brown / Yellow thin cable. This cable measures NOTHING, not a thing not a constant live or a ignition live??? (the alternator terminal this goes to is labelled (D+)

Terminal 3 - labelled (W) - havent got anything connected?

I have some questions?

im beginnning to wander if there was infact anything wrong with my old alternator abd weather the problem lies in a broken cable somewhere?

can anybody kindly explain what B+ (1) , D+(2) and W (3) stand for?

Should the brown/yellow cable that goes to terminal 2 be a ignition live or something?


Any help would be greatly apprectiated, I know is christmas eve, but I really need it tomorrow!!

[kingcreaky]

forgot to attach

http://www.creak-it....ernator/alt.JPG

[Dev]

Sorry for the late reply, you appear to have the alty wired correctly.

I would follow the alty back and check coil etc until you get to the ecu.

I would also check your earth in the boot, for some reason rover liked to put bent washers between the cable and earth point.

Dev