(1) When battery is in low state of charge.
i. This state will be shown by lack of power when starting, poor light from the lamps and hydrometer readings blow 1.200 and may be due to the dynamo either not charging or giving low or intermittent output. Check the ammeter reading when the vehicle is running steadily in top gear with no lights in use; a definite steady charge should be indicated. The charging warning light will not go out if the dynamo fails to charge, or will flicker on and off in the event of intermittent output.
ii. Examine the charging and field circuit wiring, tightening any loose connections, or replacing broken cables. Pay particular attention to the battery connections.
iii. Examine the fan and dynamo driving belt; adjust tension as necessary.
iv. If the cause of the trouble is not apparent, have the equipment examined at a service depot.
(2) Battery has overcharged. This will be indicated by burnt-out bulbs, very frequent need for topping-up of battery and high hydrometer readings. Check the ammeter reading when the car is running steadily with a fully charged battery and no lights or accessories in use, the charge reading should be of the order of only 3-4 amperes. If the ammeter reading is in excess of this value, it is advisable to have the regulator setting tested and adjusted if necessary at a service depot.
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