Disco 3 (LR3) Dashboard Battery Light

Hi all

Hope all is well

Quick Q. due to what is happening around the country at the moment we've not used the D3 for a month now as we've been using her FL1 if we need to go any where

This morning i had to commute to my office which is a 82 mile return journey, after getting there no dramas i started the D3 back up and the dash battery light appeared, now having 6-8 weeks back having the battery voltage checked ect i was a tad annoyed. On the trip down i had 2 USB leads plugged in and the heaters on as it was fresh i then noticed the radio say " Low Power Mode " so everything was unplugged and turned off. I put my foot down a bit on the M6 north and then noticed the battery light had disappeared. I put the radio back on and all was then well. Would it be fair to say because its not been used which may have caused the issue or do i need to look elsewhere why the light had come on and gone again?

Cheers

I’d say the alternator is not charging properly,

johnlad said:

I’d say the alternator is not charging properly,

Click to expand...

Cheers John, i'll get it checked or is this something that a home mech can check?

You can check yourself if you have a basic voltmeter. Read the voltage with the ignition off, with ignition on and then with engine running at idle. If there's 2 of you, you can check the voltage while the starter is turning the engine.
If you're able, then post your readouts

kermit_rr said:

You can check yourself if you have a basic voltmeter. Read the voltage with the ignition off, with ignition on and then with engine running at idle. If there's 2 of you, you can check the voltage while the starter is turning the engine.
If you're able, then post your readouts

Click to expand...

Cheers, will do this afternoon

Hi again

Battery Voltage 12.77v DC
Ignition ON 12.60v DC
Engine ON 12.53v DC

Cheers

Ok, battery isn't shot, but you're not getting any charge. Check the main cable and connections from alternator to battery as a start

Ok will do, is this easy enough or do i have to start removing things?

No idea sorry, never looked under the hood of any discovery!

Cheers, just been watching vids on YT ha ha i think i know what the crack is now

Thanks for your help mate

andyschleckscheshirecat said:

Cheers, just been watching vids on YT ha ha i think i know what the crack is now

Thanks for your help mate

Click to expand...

Hi I hope you don't mind me asking , but which YT vids did you watch? coz I have a D4 and it was recently full serviced however I had the same thing happen
around last Christmas
but I was driving with all four heated seats on plus lights widscreen wipers fan heater and stereo and, everything went back to normal when I switched all the heated seats and stereo off.
Thanks.

Hi, i just typed in " Land Rover Discovery 3 TDV6 Alternator Replacement " it brought up quite a few

I am wondering if i have some gremlins in the system as mine has had an easy life and covered 85k miles

Before i start getting the alternator changed i am going to check the cable route and connection of the item at the engine side

Cheers

andyschleckscheshirecat said:

Hi, i just typed in " Land Rover Discovery 3 TDV6 Alternator Replacement " it brought up quite a few

I am wondering if i have some gremlins in the system as mine has had an easy life and covered 85k miles

Before i start getting the alternator changed i am going to check the cable route and connection of the item at the engine side

Cheers

Click to expand...

Thanks

Just a thought, the one on my car often took a few seconds to spring to life. Might be worth blipping the throttle and rechecking the voltage

kermit_rr said:

Just a thought, the one on my car often took a few seconds to spring to life. Might be worth blipping the throttle and rechecking the voltage

Click to expand...

I have just been out to the car after studying my Haynes manual, i pulled out the F20 5A fuse from the battery fuse box and restarted it, the light came on i gave it some gas and it disappeared. I'll do it again over the weekend and check the voltage. Maybe an intermittent thing either way i'll get an alternator next month and change it myself

andyschleckscheshirecat said:

I have just been out to the car after studying my Haynes manual, i pulled out the F20 5A fuse from the battery fuse box and restarted it, the light came on i gave it some gas and it disappeared. I'll do it again over the weekend and check the voltage. Maybe an intermittent thing either way i'll get an alternator next month and change it myself

Click to expand...

If your going to change the alternator only use a Denso one, it’s a smart alternator, apparently the car’s electronics don’t like imitations.

johnlad said:

If your going to change the alternator only use a Denso one, it’s a smart alternator, apparently the car’s electronics don’t like imitations.

Click to expand...

Cheers John will do

This is pretty much an indispensable bit of kit, leave plugged it at all times, quick visual is all thats needed, amazing what the volts can reach in winter.
https://www.ebay.co.uk/itm/LED-CAR-...164475?hash=item4d8f73103b:g:NrgAAOSwwPtcfmce

A bit surprised that no one has suggested switching all electrical systems on and to full power and then testing the voltage at the battery, with the engine running. This was always the test of alternator function in the old days. Do alternators now function in some magical fashion which means this is no longer a proper test? Used to be lookin for 14 odd volts under theses conditions to be sure.

Stanleysteamer said:

A bit surprised that no one has suggested switching all electrical systems on and to full power and then testing the voltage at the battery, with the engine running. This was always the test of alternator function in the old days. Do alternators now function in some magical fashion which means this is no longer a proper test? Used to be lookin for 14 odd volts under theses conditions to be sure.

Click to expand...

That's also a good test, but if the battery isn't being charged at idle and no load there's definitely something amiss