What Voltage Should Alternator Charge At. In this manner what should an alternator charge at. A few days later I checked the voltage of the battery while the engine was running and I got 138V.
Answer 1 of 8. The alternator will charge the battery at a constant voltage usually 138 or 142 and electively never a constant current. Your line of thinking is correct in that a good alternator should be charging in the 141-145vdc as long as theres no major load on it.
Stress test the alternator Place a load on the alternator by turning on the headlights the radio and the air conditioning.
Answer 1 of 8. If these test are good then i believe the charging system is doing its job. Allows battery voltage from the ignition to flow to the alternators field coil during startup. If there is a setting in VCDS that can bet set to tell alternator to charge battery all the time when battery is low even if seat warming is on or not or when braking or not it would do the miracle.
