W124 300TD Alternator-Battery Light

[cdc02254]

Before I start taking out the alternator is there anything else I should check?

Driving home last night my ABS light started to come on then the radio cut out when I put the blower up full, I quickly realised there was a battery issue got the car home turned it off then tried to restart but nothing.

Charged battery, turned key and no battery light coming on.

Any Ideas!

 

[tagnut]

Before taking out the alternator check it's output with a multimeter - it should be 14.4V. A fully charged battery in good condition will quickly drop to 13.2V when you stop charging and then slowly to 12.6V thereafter.

 

[Ted]

No battery light coming on?
Does it come on when you ground the warning light wire at the alternator? If it does, it's probably the alternator (most likely the regulator/brushes). If it doesn't, most likely the warning light bulb.

 

[cdc02254]

Well the battery is now dead, so im charging the booster ready to start it then ill check with a voltmeter.

 

[cdc02254]

Multimeter reading 11.7v

 

[tagnut]

Is that on the battery? If so it is fully discharged. If you've had it on charge and it's still showing this it's knackered!

 

[cdc02254]

the battery had run dead, I started the car on booster and then put the multimeter on the battery.