The P0622 code in your 2020 Dodge Charger indicates a malfunction in the generator field control circuit. The field circuit controls the electromagnets inside the alternator that determine charging output. When this control fails, the alternator cannot properly regulate its output, potentially leading to over or undercharging.
Field Control in Modern Alternators
Your Charger's alternator uses an electronically controlled field winding. The PCM commands different field strength levels to adjust charging output based on demand. Stronger field current increases output; weaker field current decreases it. P0622 means the PCM has detected a problem in its ability to control this field circuit.
Causes of Field Control Malfunction
Alternator internal regulator failure is common—the regulator controls field current based on PCM commands. Open or shorted wiring in the field circuit between PCM and alternator causes control loss. Corroded connectors affect signal quality and current flow. In some cases, the PCM's field control driver has failed.
What You May Experience
Battery warning light illumination is typical, often accompanied by the check engine light. Voltage may be unstable—check your gauge for readings significantly above or below 14 volts. Electrical accessories may behave erratically, and battery life may shorten due to improper charging. In severe cases, the battery dies leaving you stranded.
Diagnostic Approach for Your Charger
Using Chrysler wiTECH, monitor field control commands versus actual output. Check alternator output voltage across the operating range. Test field circuit wiring for continuity, shorts, and proper voltage. Many Charger alternator issues stem from the internal regulator, which is often replaceable separately from the alternator on some models.