Vehicles after change point in 1982
Testing Requirements:
- Correct connections on charged battery
- Correct connections on alternator and starter
- Good ground connection between engine and body.
- Tight drive belt

Indicator Lamp On Continusously:
Remove voltage regulator and check carbon brushes, replacing if necessary - 12 31 200.
Distance "V" for new condition = approx. 12 mm (0.472").


12 31 200

Installation:
Check slip rings for wear, fine grinding and polishing if necessary.
Connect BMW service test unit.
Start engine and compare test values with nominal values*.
*See nominal value microfiche

If the battery charge indicator lamp goes out while engine is running and the
regulating voltage* is not reached - harmonic wave ratio and oscillograph okay (as shown)
- the voltage regulator has to be replaced, see 12 32 000.


12 32 000

Repeat test.
If the specified charging current is not reached, remove and disassemble alternator, and
inspect components - 12 31 020 / 513.


12 31 020
12 31 513

Oscillographs of Defective Alternator:
Defective power or exciter diode.

Shorted turn of stator coil.

Break in one exciter diode.