P0622

Generator Field/F Terminal Circuit

Q: Is it safe to drive with P0622?

Only for short distances. If the alternator isn't charging, the car runs off the battery and will eventually stall. Address it before longer trips.

Q: Can I just clear P0622?

It will return while the field circuit or alternator is faulty. Clearing it won't restore charging — repair the cause.

Charging system Generic OBD-II High

What it means

P0622 means the ECM detected a fault in the generator (alternator) field 'F' terminal circuit, which the module uses to control charging output. A problem here can stop the battery charging properly and turn on the charging warning light. It is usually a wiring, alternator, or battery issue.

High

Can I keep driving? Limit driving — if the battery isn't charging you can be left stranded once it drains, and electrical systems may act up. Get it checked soon.

Real-world scan data

Seen in

260

scans in the past year

Found in

<0.1%

of scans

0.1%

of scans that found faults

Appears alongside · share of P0622 scans

P0683in 21.1% of scans

P0110in 19.2% of scans

Figures reflect only diagnostic scans recorded through our own apps and tools. Cars are typically scanned because a symptom or warning light prompted it, so these counts describe our scan records — not the incidence of faults in any model, and not the quality, reliability, or safety of any vehicle. No comparison between manufacturers or models is implied. All trademarks belong to their respective owners; no affiliation or endorsement is implied.

Common symptoms

What you'll notice

Battery / charging warning light on the dash
Battery discharges or won't hold a charge
Dim lights or erratic electrical accessories
Difficulty starting as the battery weakens

Common causes

Most likely first

Damaged or corroded wiring in the generator field circuitLikely
Loose or poorly connected field/F terminal wiringCommon
Failed generator (alternator)Common
Weak or failed batteryLess often
Failed engine control module (ECM), least likelyLess often

How to diagnose & fix

Work through it in order

Test battery and charging-system voltage with the engine running (should be roughly 13.5–14.5 V).
Inspect the generator field/F terminal wiring and connector for corrosion, looseness, or damage.
Load-test the battery and replace it if weak.
Test the alternator's output and field control; replace the alternator if it fails.
Repair the field circuit wiring, then clear and re-test charging.

FAQ

Quick answers

Is it safe to drive with P0622?+

Only for short distances. If the alternator isn't charging, the car runs off the battery and will eventually stall. Address it before longer trips.

Can I just clear P0622?+

It will return while the field circuit or alternator is faulty. Clearing it won't restore charging — repair the cause.

Read & clear P0622 yourself

Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.

▶ Get it on Google Play

✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX