ignition light won't go out

[andygod]

Help
Ignition light won't go out when the keys are removed and alarm key fob won't set the alarm. Alarm can be set with the key and ignition light goes out when the engine is started. This happened to me many moons ago when the alternator was on its way out, hope it’s a simpler problem this time. Engine is very dirty (covered in dust and light mud) fan belt is slipping. I was in a lot of water and mud last weekend. Engine is a 3.5 V8, any ideas why the ignition light won't go out.

[imspanners]

Hmmm, mud + water + alternator.....?

See where this is going?

Try disconnecting the B+ wire from the back of the alternator.
If the light goes out, there's the problem. You could try hosing the alternator down, but I think the Rectifier diodes have gone and allowing power to feed through the alternator back to the warning light.

Replacement alternator probably required.

[ChrisW]

Andy,
Give us a shout if you need any help - sounds like alternator related, as suggested try cleaning it up and check the connections.
Had my alternator reconditioned at Vehicle Electrics in Acocks Green - same day service.

[andygod]

Hmmm, mud + water + alternator.....?

See where this is going?

Try disconnecting the B+ wire from the back of the alternator.
If the light goes out, there's the problem. You could try hosing the alternator down, but I think the Rectifier diodes have gone and allowing power to feed through the alternator back to the warning light.

Replacement alternator probably required.

Disconnected the B+ wire and the light went out, can the alternator be repaired or am I looking for a new or re conditioned unit.

[ChrisW]

Your alternator could either be a 65, 72 or 85 amp rating.
Depending on the rating replacement rectifiers range from £10 for pattern parts to £50 for genuine.
I think I paid about £80 for mine to be reconditioned which included the diode pack, bearings, new rotor and brushes.

Part numbers for the rectifiers are
72amp - STC1605
85amp - STC986
65amp - RTC5671

[andygod]

Thanks for the advice guys.
I purchased a recon alternator for £45.00 and it's now fitted and working.

[BrumLee]

Thanks for the advice guys.
I purchased a recon alternator for £45.00 and it's now fitted and working.

Hi Andy,

I was going to suggest the guy on Shady Lane. Has them on the shelf and priced around what you paid. Had one off him 3 years ago and still working  8)

[chris9119]

Thanks for the advice guys.
I purchased a recon alternator for £45.00 and it's now fitted and working.

Hi Andy,

I was going to suggest the guy on Shady Lane. Has them on the shelf and priced around what you paid. Had one off him 3 years ago and still working  8)

Yeh, but you don't go through a lot of mud like us    

[BrumLee]

Yeh, but you don't go through a lot of mud like us    

I was dreaming about it last weekend    

Was too tired after sitting in BMW Engines reception for four hours whilst the eldest did his third round interview and that after a 12 hour night shift. Always next weekend to see if I can break it    :lol:

[andygod]

Thanks for the advice guys.
I purchased a recon alternator for £45.00 and it's now fitted and working.

Hi Andy,

I was going to suggest the guy on Shady Lane. Has them on the shelf and priced around what you paid. Had one off him 3 years ago and still working  8)

Hi Lee
I did indeed purchase my recon alternator from the auto electrician on Shady lane. My last alternator lasted for about 2 years and was also from him. Hopefully the new one will last a little longer.