Battery light not on when engine is off - car won’t start

[HazzaCrawf]

Hi all,

Just a problem with my car that I’d like to get a second opinion on.

When turning the ignition on, the battery light does not illuminate like it should. The engine will try to crank but won’t start. That suggests a dead battery, however the battery voltage when tested with a multimeter is OK. Any ideas of where to look next? The car has been sat for 3 weeks.

Car is a 2005 Clio. About to get rid of it - at my wits’ end!

Thanks in advance

[HazzaCrawf]

lord trumpton said:

HazzaCrawf said:

Hi all,

Just a problem with my car that I’d like to get a second opinion on.

When turning the ignition on, the battery light does not illuminate like it should. The engine will try to crank but won’t start. That suggests a dead battery, however the battery voltage when tested with a multimeter is OK. Any ideas of where to look next? The car has been sat for 3 weeks.

Car is a 2005 Clio. About to get rid of it - at my wits’ end!

Thanks in advance

When you say 'try' to crank do you mean it's cranking properly or not?

If the battery is knackered then the voltage reading alone is not an indicator. It's the amperage that turns the car over

Try and jump start it if you have leads

Sorry - wasn’t clear enough. The engine turns over but struggles to start. Even then, the battery light doesn’t illuminate when the engine isn’t running.

Also, having just bump-started it as a last resort, the battery/no charge warning light comes on above 2000rpm, and car doesn’t restart. Faulty alternator?

[HazzaCrawf]

mickthemechanic said:

Hi


Does the engine management light come on when the ignition is turned on?

Nope, no engine light at all.

[HazzaCrawf]

stevieturbo said:

Have you just bought it or something ?

Sounds like a plethora of problems.

Had it for three years. The last year it’s been a bottomless pit!

[HazzaCrawf]

Penelope Stopit said:

HazzaCrawf said:

Sorry - wasn’t clear enough. The engine turns over but struggles to start. Even then, the battery light doesn’t illuminate when the engine isn’t running.

Also, having just bump-started it as a last resort, the battery/no charge warning light comes on above 2000rpm, and car doesn’t restart. Faulty alternator?

Warning light coming on at 2000 RPM could be down to worn alternator brushes. While looking at the alternator warning light crank the engine for a split second several times so that the alternator is being turned a little at a time, you may well see the warning light come on dimly when the alternators rotor/slip-ring is in a certain position, if the light does come on this proves the brushes are at fault and the alternator won't be charging the battery

Brilliant, thank you. According to the Haynes, the light not illuminating while the engine is off further points towards the alternator.

Thanks

[HazzaCrawf]

Cheers for all your input, guys. My confusion with the source of the fault is this:

How can a dead alternator prevent the car from starting, bearing in mind that the battery is fully charged, and the starter is functioning normally? A non-functioning alternator could prevent the battery from being charged, but this would present a problem once the engine was started and battery power was being used, I imagine?

Is there any part of the alternator that could, if corroded/degraded/eaten by a mouse, prevent the car from starting regardless of battery condition AND disable the no-charge light while the engine is off? The light appears to be working properly as it appears intermittently at high RPMs.

Please forgive me - I’m handy with spanners but electrical problems are new to me.

[HazzaCrawf]

Thank you. So this will check battery is operating correctly, and check that (enough) power is getting to the starter motor?