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alternator and battery light 900 1991

Dear joey randolph,

Hope you're well. A failed solder connection usually results from a micro-crack: an actual break so small that it cannot be seen with the unaided eye. Sometimes, a connection fails because of a layer of corrosion that may be only a few atoms wide.

The cures: to cure a solder micro-crack, apply a low-wattage soldering iron (no more than 30 watts) to each solder joint. Keep the iron on the joint only until the solder changes from a dull gray, to a shiny silver. Solder tip dwell time should be no more than two seconds. When the solder is shiny, that means the solder has liquefied, closing the micro-crack.

It is also a good idea, while you have the cluster on the bench, to remove screws, that secure instruments, and clean the contact points - and the underside of the screw heads - with ultra fine steel wool. This removes any corrosion, which may be invisible.

How many miles on this car? Alternators should be good for at least 200K miles (320K kilometers). It could be that the alternator's brushes have worn to the point, where they need to be replaced. If so, you may need to get the unit re-built or find a replacement at a salvage yard.

Check the connection of the thin red wire, at the back of the alternator.
Clean the connector. Check the wire for continuity, i.e., that the circuit has not been broken. This wire links the alternator to the cluster, which provides the excitation current needed to trigger charging.

Please post back with your findings.

Hope this helps.

Yours faithfully,

Spook






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New alternator and battery light [900][1991]
posted by  someone claiming to be joey randolph  on Thu Sep 1 22:55 CST 2011 >


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