You find out by making the fault move. Charge your car on a different charger, and charge a different car on yours: a fault that follows your car belongs to the car, and one that follows your charger belongs to the charger. If it follows neither, it lives in the third suspect most drivers forget — the circuit and outlet at that spot. Two swap tests give you the verdict.
Key Takeaways
- Assign the fault by making it move: swap the car, swap the charger, and for a portable, swap the supply.
- Three suspects, not two: a fault that follows neither car nor charger lives in the circuit or outlet.
- Record the exact message before any reset — it is half of every verdict’s evidence pack.
- Intermittent faults and full-setting faults mislead: record conditions, and let an electrician judge the circuit.
Three Suspects, Not Two
A charging session is a chain: the supply (breaker, wiring, outlet), the charger, then the car. Drivers frame it as charger versus car, but supply faults imitate both — a worn outlet can make a healthy charger report errors. Hence three outcomes below, not two.
Before any test, record the fault exactly: photograph the display or app message, and note when it appeared — do not reset first, as a reset erases the evidence every verdict needs. New to the basics? Work through the driver’s checklist for a charger that is not working once. Heat, smell, scorch marks or a repeatedly tripping breaker end the testing: those are faults to be found.
The Follow Tests
Change one variable at a time, and watch where the fault goes.
| Swap test | How to run it | What the result proves |
|---|---|---|
| Your car, a different charger | A public charger or a friend’s home unit, a normal session | Same fault there: it follows the car. Charges cleanly: the car is largely cleared. |
| A different car, your charger | Any second EV on your home charger, settings unchanged | Same fault: it follows the charger or the spot. Charges cleanly: suspicion points back at your car. |
| Your charger, a different supply | Portables only: the same unit on a known-good outlet elsewhere | Fault gone: it stayed at the first spot — that outlet or circuit. Same fault: charger or car, per the first two tests. |
A fixed wallbox has no third swap: its supply side is tested by an electrician, which is itself the verdict route when a fault stays at the spot.
Reading the Verdict — and the Two Misleading Middles
- The fault follows the car. Call the dealer, and bring the list of chargers it failed on, the same way each time.
- The fault follows the charger. Call the seller or manufacturer — this is the warranty case — with the exact recorded message and a note of which cars were tried.
- The fault stays at the spot. Call a licensed electrician, and bring the pattern: at plug-in or an hour in, every session or only some.
Two patterns mislead. First, both swap tests pass: the fault is intermittent, and only a record assigns it — note the time, how far into the session, and the conditions over a week of sessions. Second, the fault appears only at the highest setting: an over-high setting imitates a charger fault, because charging is a continuous load, sized by the NEC at 125% of the charger’s current. Our guide to why a charger keeps tripping the breaker covers that pattern; the circuit’s capacity is the electrician’s to confirm.
The Chargers in the Test
A portable makes all three swaps possible. The EV-ACS4005T is a 40 A NACS portable charger (9.6 kW, NEMA 14-50P, 16/24/32/40 A adjustable, IP66, 25 or 28 ft cable) whose 1.77-inch display states the session and any fault in text you can photograph. A fixed unit such as the EV-ACT5006T wall charger (up to 48 A, hard-wired or NEMA 14-50P, NACS, IP65/IP66, ETL/FCC/CE) runs the first two tests only. Both sit under EVDANCE’s 3-year standard warranty when the verdict lands on the unit.
Frequently Asked Questions
My car charges fine at public chargers but fails at home. Which side is faulty?
The public session clears the car, so the fault is in your charger or at your spot. Run the second test (a different car on your charger) and, for a portable, the third (your charger on another outlet) to split them.
I do not have a second car. Can I still get a verdict?
Yes: your car on a public charger covers the first test, and a portable on a known-good outlet the third. With a wallbox, the missing half is the electrician’s supply check.
The fault comes and goes. Who do I call first?
Neither, yet. Record first: the exact wording, when it appears, and the conditions. Intermittent faults are assigned by evidence — and the record is what any of them will ask for.
Related Reading
- Why Is My Electric Car Charger Not Working? A Driver’s Checklist
- Why Does My EV Charger Keep Tripping the Breaker?
- Are Home EV Chargers Safe?
