Engine Error
P0620
Generator Control Circuit Malfunction
Severity
High
Symptoms
Battery light on, dead battery, erratic electrical issues (radio off, dim lights)
Common Causes
- Faulty alternator/generator
- Broken control wire from PCM to alternator
- Corroded battery cables
- Failed PCM regulator circuit
How to Fix
- 1 Test and replace alternator
- 2 Trace and repair control wire harness
- 3 Clean and replace battery terminals
- 4 Replace PCM (if regulator is internal to it)
Estimated Repair Cost
USD
$50
–
$800
Alternator replacement: $300 - $600; Wiring repair: $100 - $200