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This is intended to gather together numerous posts on alternator and charging issues. Please add links to other relevant posts as they come up.
This post addresses battery light on issues, alternator not charging issues, alternator ground issues. Addition of likely search terms here or in your reply will make this thread show up easily on a search.
A car's charging system consists of the battery, the alternator, the battery warning light and the charging circuit. The battery stores charge and is used to start the car and to supply electrical power when the engine is off. The alternator generates electricity which charges the battery and supplies electrical power when the engine is running. The alternator consists of:
Problems that arise are basically of three or four types:
Various posts listed below address various of these issues:
If there seems to be a bit of a common thread here, yes, I did contribute to most of these threads. Not that I'm being exclusivist or anything but a search produces just sooo many results. Please add other posts that are relevant.
This is intended to gather together numerous posts on alternator and charging issues. Please add links to other relevant posts as they come up.
This post addresses battery light on issues, alternator not charging issues, alternator ground issues. Addition of likely search terms here or in your reply will make this thread show up easily on a search.
A car's charging system consists of the battery, the alternator, the battery warning light and the charging circuit. The battery stores charge and is used to start the car and to supply electrical power when the engine is off. The alternator generates electricity which charges the battery and supplies electrical power when the engine is running. The alternator consists of:
- Stator windings (these produce the output current)
- Rotor windings (these produce the magnetic field necessary for the Stator to generate current)
- Slip rings (these connect the brushes to the Rotor)
- Carbon brushes (these connect the Regulator to the Slip rings)
- Voltage Regulator (this monitors the output voltage and regulates it to charge the battery and to prevent overcharging)
Problems that arise are basically of three or four types:
- Wiring (bad ground wire, corroded wires, damaged instrument cluster circuit)
- bad voltage regulator / brushes (worn brushes or blown regulator)
- bad alternator (bad bearings, damaged or worn out windings, diodes)
- other components (Battery light bulb, charging system relay)
Various posts listed below address various of these issues:
- A troubleshooting guide here:
http://www.saabcentral.com/forums/showthread.php?t=30908 - Instructions for replacing the regulator are here:
http://www.saabcentral.com/forums/showthread.php?t=53542 - Instructions for replacing the carbon brushes within the regulator {often this is all that's wrong} are here:
http://www.saabcentral.com/forums/showthread.php?t=30596 - and why you might want to have the alternator rebuilt anyhow is here:
http://www.saabcentral.com/forums/showthread.php?t=27280 - How the alternator should be wired up here:
http://www.saabcentral.com/forums/showthread.php?t=30072 - Something on the system relay and instrument panel circuit here:
http://www.saabcentral.com/forums/showthread.php?t=54644 - Removing the alternator in the first place!
http://www.saabcentral.com/forums/showthread.php?t=53641
If there seems to be a bit of a common thread here, yes, I did contribute to most of these threads. Not that I'm being exclusivist or anything but a search produces just sooo many results. Please add other posts that are relevant.
That's a fantastic guide 
