Battery light in Tdi Defender - Help !

[VladTepes]

OK so the last few times I've driven the Deefer, the red battery light has been constantly illuminated. I thought it might have been due to the rain or something but it seems to be permanently on when the car is !

What's the likely culprit? Dead battery? Dead alternator ? Something else?

Please le me know what checks I can do to track this down. Oh and if you tell me to use a multimeter please be VERY specific eg what to set the MM to etc.

Thank You

[Shoogs]

Mine was a poor/loose connection to the starter motor... Go figure... Triple batteries though...

[pommy]

Mine was dead alternator

[VladTepes]

Hmm what's an alternator cost and is there any point / worthwhile upgrading the alternator ?

[schuy1]

Yes will be the alternator dying/dead or just a loose connection on the back. Check it b4 you plunge on a newie. The originals can be rebrushed and rebearinged, they are just a nippondenso anyway. About 2-350 for a new 1.
Cheers Scott
Dang it! got keen on hitting the post button! Any way check the voltage output on the alternator, connect the MM to the battery is easisest, put it on the seat beside you and note V, start the engine and take note if the Vs rise. If not its sus.

[GuyG]

Mine was a snapped bolt holding the serpentine belt tensioner on:o still trying to get the bloody thing out. Then I discovered that I didn't have power steering either or water pump for that matter.

Have you had a look under the bonnet to check the wires are still attached to the alternator?

If you can take the car to an auto electrician and ask them to check the battery etc they should check to confirm that its being charged as part of the process. This should narrow the fault.

[GuyG]

Could always check if MR Auto have a 2nd hand one.

[Blknight.aus]

pretty sure Ive got a couple of working TDI ones hanging around if you need a loaner,

check your battery voltage with the engine running if its over 12.8V the alterntors doing something switch on all the electrics and if it doesnt dip then you can keep drivign for a while till you can get it fault found.

[Reads90]

As said alternator

By the fact you can drive it and worrying about the light being on tells me it not the battery.

[weeds]

If it is your alternator........I upgrade to the 100amp disco unit

The only thing you have to do is decided whether you run a disco or defender sure time belt.....I didn't bother swapping the pulleys over so I now run a disco belt

Drop around if you like.....at this stage I'm home all day

[Reads90]

If it is your alternator........I upgrade to the 100amp disco unit

The only thing you have to do is decided whether you run a disco or defender sure time belt.....I didn't bother swapping the pulleys over so I now run a disco belt

Drop around if you like.....at this stage I'm home all day

That what I was going to say

I did the same on both my defenders

100amp instead of 65amp

Helps with winches, fridges and stuff

[VladTepes]

Sure time belt?

[weeds]

Serpentine belt....sorry auto correct

The disco run a longer belt from memory or is it shorter......

[Blknight.aus]

discos run a shorter belt after 94. (when the switched to the 100A alternator to deal with all the optional extras)

it makes the tacho read high.

[VladTepes]

So can the higher putput alternator be fitted w/out affecting the tacho reading ?

[Reads90]

So can the higher putput alternator be fitted w/out affecting the tacho reading ?

Don't you have a defender

The don't have a tacho anyway so why do you care :-)

[Bushie]

Don't you have a defender

The don't have a tacho anyway so why do you care :-)


Unless one has been fitted :)

Martyn

[Reads90]

Unless one has been fitted :)

Martyn

Yeah but it's a diesel why do you need a rev counter.


All you need on the dash is a temp gauge. :-)

Speedo is just a guide anyway. :-)

[Blknight.aus]

So can the higher putput alternator be fitted w/out affecting the tacho reading ?

yeah, you just swap the pully over.

its just the Windings wrap count, wire size, and diodes that change between the 2

[VladTepes]

Thanks. I have it booked into MR's for Wednesday but will check those other things mentioned on this thread in the meantime.

[VladTepes]

UPDATE:

It most certainly WAS the alternator.

Warren showed me the old one they pulled out. As well as being decidedly "2nd hand" (so to speak) the bearings had collapsed. Turning the shaft made it sound like a tortured horse (or so I would imagine).

On the upside I now have a nice shiny new 100A alternator.

Thanks all for your help / input / advice.