Thread: Alternator failure without warning - can it be anything else?

Hi Steve,

I was in a similar situation for the last 8 weeks, but the D3 ceased to function last week, with a very flat battery. When the battery light originally came on, I checked the alternator, which was pumping out 13.5v at idle and thought nothing more of it. Now there seems to be a short in the system. Luckily the battery, which is only 6 mths old, recovered with a good charge, and starts the car no problem, but there is now a constant load on the battery which shows 11v at all times when connected (even at idle), and 12.7v when I remove the earth terminal. I'm guessing the alternator is completely goosed now, and I'm very reluctant to drive it anywhere in it's current state.

As a result of my experience, I would suggest doing something before it leaves you high and dry.

Regards
Grant

Walking is the risk as I see it and perhaps wet as in up the creek.

My view is that normal alternator testing techniques tend to show the alternator is OK because the testing techniques do not take into account the "smart regulator" built into the Denso alternator.

While LR and Denso call the regulator "smart", I call it dumb, as the regulator takes instructions rather than gives them. In the past, the regulator looked at the battery and decided how much power the alternator should produce.

In the case of these PWM, (Pulse Width Modulated), style regulators in our Denso alternators, the regulator takes its instructions from the engine computer, not the battery. Normal old style alternator testing techniques do not simulate the newer Engine Computer generated instruction sets.

In other words, the alternator is probably OK, however the internal regulator is sick, but diagnosing that takes special testing equipment not normally found even at a LR dealership.

There are some alternator related files at the bottom of the page re the link below.

Regardless of where you get your alternator, count the number of grooves in the pulley to make certain the new pulley is the same as the one you are taking out. You may have to swap pulleys - that is the old pulley on the new alternator.

DISCO3.CO.UK Photo Gallery - LR3 miscellaneous

Thanks for that info bbyer!

Next question - Where to buy a new alternator from?

I bought mine from Karcraft in Sydney. $430.

From intermittent noise in my alternator, I may have change it soon, (nearest service over 1600k's away)
Can anybody direct me to where I can find guide to removing and refitting alternator in D3 2.7.
Many thanks, vbrab

From intermittent noise in my alternator, I may have change it soon, (nearest service over 1600k's away)
Can anybody direct me to where I can find guide to removing and refitting alternator in D3 2.7.
Many thanks, vbrab

http://www.disco3.co.uk/forum/topic82516.html

There you go
Rich

Much appreciated Rich, I spent an hour last night removing various plastic parts including the drivers side inner arch etc, which gave me no better access!