Guys

Had alternates replaced on Friday as car battery kept dying when message coming on radio display saying please turn on engine system will be shut down in 3 minuets. Had alternator tested and was only throwing out 5volts. All working ok till now as the same had happened. Noticed a strange smell then saw message. Stopped the car now it won't start just clicks over anybodt with any ideas.

Regards
john

 

discojohnno,

Can you provide more details as to what vehicle you are driving?
- Model, year etc?

 

If I were you, I'd go straight to a proper auto-electrician, tell him what's happened and ask him to look for any shorts; mention the strange smell. This kind of thing can easily set the vehicle on fire -- immediate write-off.

Leedsman.

 

Thanks for reply guys. It's a grand voyager 2.8 auto. 2006. The burning smell is definitely coming from the replacement. Alternator would anything cause this to happen ??

 

discojohnno,

Happy to hear you've found the source of the burning smell.
The new alternator itself could be the issue, is it a Mopar part?

 

Happened to me with a brand new original alternator on a 2001 Dodge RamVan I used to drive.
New original alternator replaced by the dealer and it burned out within 2 months.
Horrible smell.
I cursed at the mechanic and he replaced it, No charge of course

 

hi, not sure what you mean by mopar part, but the burning smell definitely coming from alternator.

Could anything cause the alternator to fail?

Regards

John

 

Testing an alternator for a short is easy; install a fully charged battery after having disconnected the heavy-current lead from the stud on the alternator. Be careful not to drop the nut in the works. Then simply wire your modest current test lamp from battery +ve. to alternator stud. The lamp should not light.
Alternatively, an ohm-meter can be used on its lowest ohms setting, one clip to chassis, one clip to heavy-current stud, again disconnected. One way round for the meter will show a current, the other way round not, even on the highest setting of the meter. The test-lamp is best as it tests at 12volt, whereas the ohm-meter probably at 1.5volt. The lower the test lamp wattage, the better.
Explanation:
Each of the six windings of the alternator has a diode (rectifier) in its earthy end, usually the stud-diodes are press-fitted into a rectifier plate which acts a a heat sink. All the other ends of the six windings are connected together at the heavy-current output stud. These are heavy windings and have little resistance. This means no current will flow INTO the alternator so long as the voltage applied is positive, as it is from the battery. This is why so much damage can be caused if a battery is connected the wrong way round. Hope this hasn't happened in your case.
These diodes are known to short at times.

Leedsman.

 

Guys 2nd alternator was fitted and everything has been fine since