Renault megane 1.5dci 55 plate - Battery light but battery is fine

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Thu 21 Jan 2016 11:06
Renault megane 1.5dci 55 plate - Battery light but battery is fine - fallenangel

Hi all, I have a Renault megane 1.5dci 55 plate. Looking for some help so i dont get mugged of at the garage. The problem is the battery light is on when i start the car and sometimes have trouble getting it to start. Even after a long drive when i next start the car the battery light is once again lit up. I have had the battery tested and its fine, ( new battery last year) I had a gadget put onto battery and it says charging ok but not at maximum capacity. Would it be the alternator, Sorry female here and dont know much about cars.

Any help appreciated

Many Thanks

Katie

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Thu 21 Jan 2016 11:53
Renault megane 1.5dci 55 plate - Battery light but battery is fine - hardway

You do realise many people responding here work in or run garages?

But nevertheless your going to have to go to a garage and get the battery properly tested with a load tester,

and the alternator properly tested,

I don't know what "gadget" you had testing the alternator but either you didn't understand the explanation or they screwed up the test.

For future reference when the battery/alternator light is on that means only one thing,

for wahtever reason the battery IS NOT CHARGING.

Not surprising it fails to start sometimes.

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Thu 21 Jan 2016 17:40
Renault megane 1.5dci 55 plate - Battery light but battery is fine - Cyd

The battery light means the battery is not being charged. Have the alternator checked.

As you drive, the battery is discharging. When it becomes fully discharged your car will stop without further warning.

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Fri 22 Jan 2016 00:12
Renault megane 1.5dci 55 plate - Battery light but battery is fine - Peter.N.

If you can lay your hands on a simple multimeter, connect it across the battery with the engine running and it should read about 14.4 volts, much less and you have an alternator problem.

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Fri 22 Jan 2016 08:02
Renault megane 1.5dci 55 plate - Battery light but battery is fine - Railroad.
The charging lamp permanently on means you have a fault with the charging system, but the alternator is a complex component and many things can be wrong with it. Because of this it doesn't necessarily mean it's not charging, because it very much depends what's wrong with it, but you almost certainly need a new one. Similarly it doesn't necessarily mean it is charging if the lamp does work properly.

For a girlie explanation dashboard warning lamps are colour coded for easy identification.

An orange warning lamp means you have a fault which requires attention at the earliest convenience.
A red warning lamp means you have a fault which requires immediate attention.

If you ignore a red warning lamp and continue to drive regardless then make sure you have vehicle breakdown cover because you will need it.

Edited by Railroad. on 22/01/2016 at 08:04

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