P0622Charging System

Generator Field/F Terminal Circuit

P0622 indicates a fault in the generator field (F terminal) control circuit, which regulates alternator output. It can be wiring, the regulator, or the alternator.

🚗 Risky. Charging control faults can strand you or cause electrical problems. Address it promptly.

HIGH

severity

🎯 Top Causes, Ranked by Likelihood

#1Faulty alternator or voltage regulator$300-$800

40%

The field circuit inside the alternator or regulator has failed.

#2Wiring or connector fault$40-$300

30%

Damaged wiring in the field control circuit.

#3Poor ground$0-$100

20%

A bad ground disrupts field control.

#4Control module fault$200-$900

10%

Rarely, the controlling module fails.

🩺 Common Symptoms

Battery warning light
Overcharging or undercharging
Check engine light
Electrical glitches

💰 Repair Cost: DIY vs Shop

DIY Cost

$0-$400

Shop Cost

$150-$800

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose P0622

1Measure charging voltage

2Inspect the field circuit wiring and connector

3Check grounds

4Test or replace the alternator or regulator

❓ Frequently Asked Questions

Can I drive with P0622?

Only briefly. Field control faults can cause over- or undercharging.

How much to fix P0622?

Often an alternator or regulator, $150-$800 installed.

Is P0622 serious?

Yes. It affects charging regulation and the electrical system.

🔗 Related Codes

P0620P0621P0625P0626