The dealer can't reproduce your Audi's charging problem: why that's normal, and what to do

Few things sting like driving your Audi to the workshop because charging keeps failing, only to be told the technicians ran every test and "everything passes." You drive home, plug in, and within an hour the same fault is back. This isn't the dealer being lazy or dishonest. It's a real, well-known pattern, and there's a logical reason for it.

Why charging issues vanish at the dealer

Dealer workshops almost always test EV charging on their own bench: usually a recent, well-maintained 22 kW wallbox on a dedicated, properly earthed three-phase supply. That setup is, by design, a near-perfect charging environment. Many home-charging faults disappear in front of it for one simple reason: the home environment has variables the workshop doesn't.

The most common reasons a fault is real at home but invisible at the dealer:

• Earthing quality. Audi BEVs, especially MEB-platform cars like the Q4 e-tron, are sensitive to earth-loop impedance. A marginal home earth that the wallbox tolerates 90% of the time will look fine at the dealer's clean supply.
• Grid noise and voltage sag. A long supply run from the street, heavy neighbouring loads, or an older consumer unit can produce brief voltage dips. The OBC sees them, the dealer bench never does.
• RCD type mismatch. A Type A RCD without built-in DC fault detection paired with a wallbox that expects either Type A with 6 mA DC detection or Type B can trip randomly under load.
• Cable wear. A worn Type 2 cable causes intermittent control-pilot dropouts at home but isn't used at the dealer test.
• Software/account state. Departure timers, location-based charging rules, and Plug & Charge contracts in the myAudi app behave differently at a known "home" location than at the dealer.
• Temperature. A morning frost, a hot afternoon, or a freshly driven warm pack all change what the BMS will accept. The workshop test is usually run mid-shift at indoor temperature.

How to make the next visit count

The biggest single thing you can do is bring evidence. A vague "it doesn't always charge" gives the technician nothing to act on. A short log gives them a fault to chase.

For each failed session, capture:

1. Date, time, ambient temperature.
2. Location (home wallbox brand and model, or public station operator and bay number).
3. AC or DC, requested kW, delivered kW, target state of charge.
4. Battery state of charge at start and at the point of failure.
5. Exact message on the car's display and on the charger.
6. A photo of the screen if there's a code or text.

A week of those notes turns "intermittent" into a pattern. Many cases show, for example, "only on the home wallbox, only below 5°C, only when state of charge is under 20%." That's diagnosable.

Eliminate the cheap variables first

Before the next dealer visit, try to rule out the things the workshop won't easily test:

• Swap the AC cable for a known-good one such as a Voldt® Audi-compatible Type 2 charging cable. If the fault stops, you've saved everyone a long diagnostic appointment.
• Try a friend's wallbox or a public AC point. If the car charges fine there, the issue is your supply, not the car.
• Ask an electrician to verify earth-loop impedance and RCD type at your wallbox.

Bottom line

"Cannot reproduce" usually means "cannot reproduce in this controlled environment." Bring data, rule out the cable and the home supply yourself, and the next visit becomes a targeted repair instead of another inconclusive test.