My Aiways U5 will not DC fast charge but charges fine on AC. What does that tell me?

It narrows the fault to the DC path and the handshake. On a European U5 the CCS2 connector does not talk to the battery management system directly — a vehicle charge control unit (the EVCC) translates between the European CCS2 protocol and the Aiways protocol, and it monitors CP, PP and PE. If AC works and DC does not, the on-board charger is proven good enough for the AC side, and the first things to read are the control-pilot faults: a duty cycle, voltage or frequency outside the expected window all point at a handshake that never completed.

My U5 starts a DC charge and then stops after a few seconds. Why?

Two common causes sit behind this, and they are told apart by the codes. The first is a handshake that fails part-way, which throws one of the three control-pilot faults (duty cycle, voltage or frequency). The second is temperature: the manual sets a limit at which a hot DC charge port is recorded as a fault and the car limits power, and a higher limit at which it requests a shutdown — which the driver sees as the gun tripping shortly after the session starts.

Nothing charges at all — neither AC nor DC. Where do I look?

When both sides fail, the handshake codes are less likely to be the answer. Look at the on-board charger for input under-voltage and over-voltage, and for power-board and charge-gun over-temperature faults, and at the voltage converter for overcurrent on its low-voltage and high-voltage sides along with any start-up fault. A converter that cannot initialise will not power the system up at all.

The charging session ended when the power went off, and now the car will not resume. Is that a fault?

Not necessarily. The manual treats resumption after a grid interruption as behaviour, not as a fault. A card-operated or public charger needs the card presented again before it will resume; a home charger of the type that can restart on its own will carry on by itself. If yours simply waits for you to authenticate again, that is what it is designed to do.

The charge port flap or the connector lock will not open. Can I force it?

Do not force it. The manual documents an emergency release for the connector lock on the EU car, and it is intended only for the case where the normal unlock has failed, and only for short-term use — it is not a routine way to unplug. For the flap itself, the manual covers the lock and the assembly but not the fuse that feeds the flap drive, so we do not pretend to give you a fuse number for it. If the normal release does not work, this is a job to hand to a workshop rather than to lever by hand.

Aiways U5: charging problems

The charger starts and then stops. Or DC fast charging fails while AC works perfectly. Or the gun will not come out at all. On an Aiways U5 the first useful thing you can do is not guess — split the fault in the right order. DC-only failures point at the handshake between the charger and the car; failures on both AC and DC point somewhere else entirely. This page sets out that order, the codes that identify a failed handshake, and — just as importantly — the parts of this the manual does not settle, so you know when to stop looking for a tidy answer.

1. First split: DC only, or AC and DC?

Almost everything that follows depends on one question. Put the car on AC (the slower, everyday connection). If it charges, the fault is confined to the DC path and the handshake. If it does not charge either, the fault is more likely downstream, on the on-board charger or the voltage converter.

On a European car there is a piece of hardware in the middle of this that is worth understanding, because it changes where you look. The European car uses CCS2, and that does not speak the Aiways battery management system's native language. A vehicle charge control unit — the EU-specific unit the manual refers to as the EVCC — sits between them and performs the conversion. It also monitors CP, PP and PE — the control-pilot, proximity-pilot and protective-earth signals — drives the connector lock, and wakes the battery management system over a hard line or the network.

Practical consequence: on a DC failure, CP is the first signal to care about. On an AC-only failure, the control unit is reporting the connector's own status back to the car, and the fault tends to be in that reporting or in the charger behind it rather than in the high-voltage path.

2. Things that look like a fault but are not

Before you pay anyone to diagnose a fault, rule out the refusals the car makes on purpose. These are documented behaviour, not failures:

What happens	Why
No charge with both guns in	With a fast-charge gun and a slow-charge gun inserted at the same time, the car will not charge. It is not a fault; it is a condition.
Will not switch on / will not start charging after plugging in	The car needs to be in P or N with an absolute vehicle speed below about 3 km/h before it will move to ON and begin. Selecting a drive gear or a non-zero speed after plugging in will stop it.
Charging refused in unusual temperatures	Charging is allowed only inside a battery-temperature window (the manual gives roughly 0 to 55 degrees C, calibratable). A related, wider window applies to the high-voltage relay warm-up. Outside it, refusing to charge is the car protecting itself.
Will not resume after a power cut	A card-operated charger needs the card presented again to resume. A home charger that supports automatic restart will resume on its own. Waiting for the car to sort itself out is not always reasonable.

If your symptom is one of these, you do not have a fault to chase. If it is not, move on.

3. DC charging stops by itself: the two things to separate

A session that starts and then aborts after a few seconds to a minute has two common causes, and the codes tell them apart.

The first is a handshake that never completed. The control-pilot signal is how the charger and the car agree on what the charger can deliver before the contactors close. When that agreement fails, the car throws one of three faults, and which one it is tells you how the signal went wrong. A normal control-pilot signal is around 1 kHz, above 8% duty cycle, with a voltage that sits in the expected logic band — a diagnostic device reads the duty cycle, the voltage and the port temperature on the charge control module.

The second is heat at the charge port. The manual sets two thresholds at the DC charge port: past the lower one the car records a fault and limits power, and past the higher one it records a more serious fault and asks the whole vehicle to shut down — which is exactly what a driver feels as the gun tripping. AC has its own, higher, thresholds for limiting and for stopping. A port that runs hot is a clue about the port and its connection, not about the charger on the wall.

4. Reading the codes: start with CP

The three control-pilot faults are the fastest way into a DC failure. They are listed below by what they mean. The setting conditions in the two columns are from the manual.

Code	What it means	When the car sets it
P148403	Control-pilot duty cycle abnormal	Duty cycle outside 0 to 8% for about 2 seconds
P14841C	Control-pilot voltage abnormal	Voltage outside 4.0 to 7.0 V or outside 7.5 to 10.0 V, each for about 2 seconds
P148538	Control-pilot frequency abnormal	Frequency outside 900 to 1100 Hz for about 2 seconds

All three mean the same thing in practice: the car could not agree with the charger on the control-pilot signal, so it refused or aborted the session. If you see one of these, the problem is in the signalling chain between the connector and the charge control unit — which is also where a worn connector, a bent pin or a damaged cable will show up.

5. If AC fails too: the on-board charger and the converter

When neither side charges, the handshake is not where to start. The manual groups these faults by the component that owns them.

On-board charger:

P148016 / P148017 — input under-voltage and over-voltage. In charging mode, below about 70 V or above about 275 V.
P12A500 — power-board over-temperature, above about 133 degrees C for 3 seconds, recovering below about 105 degrees C for 60 seconds.
P14A498 — charge-gun over-temperature, from the socket sensor above about 100 degrees C, recovering at or below about 80 degrees C.

Voltage converter:

P120019 / P120119 — overcurrent on the low-voltage and high-voltage sides, above about 216 A for 20 ms and 25 A for 10 ms respectively.
P122100 — low-voltage current feedback open loop, when the PWM is outside the 90 to 110 kHz band.
P12F800 — CAN initialisation failure. After ten failed attempts the converter cannot power up at all, so the fault looks bigger than it is.

One honest note on the fault code list. These are the codes the manual documents for the integrated charging system. What the manual does not give is a single decision tree that says "DC will not charge, therefore X". It documents the signals, the thresholds and the conditions; joining them into one answer for one car is what a technician does with the car in front of them.

6. Charge port flap stuck, or the gun will not come out

These are two different things and it is worth keeping them apart.

The gun will not release. The connector lock is meant to hold the gun while a session is live and release it when it ends. The manual documents an emergency release for the connector lock on the EU car — it is reached after removing the left-hand trim in the front compartment, and it is turned clockwise to release. It is documented for the case where the normal unlock has failed, and for short-term use only. It is not a routine way to unplug, and it is not a substitute for finding out why the normal release did not happen. Do not force the connector. If the normal release will not work and you are not certain how the emergency release behaves on your car, hand it to a workshop.

The flap will not open. The flap is driven by a lock, and the manual covers the lock and the assembly — the flap assembly itself comes off with two screws and six clips. What the manual does not give is the fuse number for the flap drive's power supply. So we are not going to invent one for you. If the flap will not open and it is not a mechanical obstruction, this is a workshop item rather than something to lever open by hand.

7. One code list, two kinds of number

This is where a lot of people waste money, so it is worth being blunt. There are two completely different kinds of number in play when you look for parts for this area of the car, and they must not be mixed up.

The first kind is the workshop manual's own document reference. This is how the manufacturer identifies a component or a procedure inside its own documentation. It is not a number you order against. In the charging area the manual uses references for the AC/DC charge socket, the vehicle charge control unit, the connector-lock emergency release, the charge-port flap assembly, and the associated diagnostic pages. You may see these if you are reading around the subject, but searching a parts counter for one of them will get you nowhere, because it was never an orderable number.

The second kind is the orderable OE part number. These are the numbers a supplier actually stocks and sells against. For this area they include the AC/DC charge socket, the charge-socket harness assembly for the EU car, the charge-socket electronic lock, and the front-bumper charge-flap assembly.

If you need a specific part, do not try to reverse one kind of number into the other. Send us the VIN, tell us which number you are looking at, and we will confirm what it actually corresponds to and the version that fits your car.

8. Are these the parts you need?

If your fault has led you to a part — the charge socket, the harness that runs to it, the electronic lock, or the flap assembly — these are the components we supply for the charging area of the U5 and U6. What we cannot do is sell you a part on the strength of a fault code alone, because the same symptom can come from the code, the wiring, or the connection, and the part is only one of the three.

See the Aiways U5 / U6 parts we supply — or, if the car is reporting a code, start from the Aiways U5 fault code index.

One honest note on numbers. The service manual documents the charging system by its own internal reference numbers, and those are not orderable. The orderable numbers for this area come from European owner and parts-supplier data instead — and these are the components we supply: the charge socket (861145100B / 861145100D / 861145100E), the harness that runs to it (861145200C / 861145200E / 861145200F), the charge-socket electronic lock (861198901), and the charging flap assembly (861885001A / 861885100). They are all listed on the parts page. What we will not do is sell you one on the strength of a code alone: send us the VIN and we will confirm which version your car takes.

9. Short answers

My DC fast charging fails but AC is fine. Is the car broken?: Something in the DC path or the handshake is failing; the rest of the car may be fine. Read the control-pilot codes first — a duty-cycle, voltage or frequency fault is the car telling you the handshake did not complete.
Can I just keep using AC while I sort the DC problem?: AC charging exercises a different path from DC, so a car that charges on AC is usable while you investigate. That is a statement about the two paths, not permission to ignore the fault — especially if the cause turns out to be at the connector or the port.
Will a diagnostic reader I buy tell me everything?: A generic reader reaches standard powertrain codes and some others, but the charging system codes above are manufacturer-specific and depend on the car being read through the right module. If you need those codes read properly, that is an Aiways-aware workshop.
Is this specific to the U5?: The architecture — a CCS2 connector, a charge control unit translating to the Aiways battery system, and the same predefined charging conditions — is shared across the U5 and U6 in Europe. The difficulty in Europe is not the technology; it is that there is no manufacturer network left to read the car.
What should I send you?: The VIN, the exact symptom (DC only, or AC and DC), and any fault code you have. Which side fails is genuinely useful information, not small talk.

Where this comes from. The charging preconditions, the temperature thresholds, the control-pilot, on-board charger and voltage converter fault codes with their setting conditions, the charge control unit's role in converting CCS2 signalling, the connector-lock emergency release and the charge-port flap details are drawn from the Aiways U5 workshop manual — the battery and discharge system description and operation, the vehicle charge control unit document, the AC/DC charge socket and connector views, and the integrated charging system diagnostic pages. The orderable OE part numbers mentioned are from the European owner and parts community and do not appear in the manual. Where the manual does not give something — notably a single causal decision tree for a DC failure, a CCS2 handshake timeout, port-terminal resistance or insulation thresholds, the flap drive's fuse number, and a dedicated fault code for the charge-socket electronic lock — we say so rather than filling the gap. Wording is our own; we do not reproduce manual pages or figures.

Important — please read before you act on anything here

This page is general information only. It is not a repair instruction, not a diagnosis of your particular vehicle, and not a substitute for professional advice. Have any work carried out by a qualified workshop or an authorised service centre. Do not attempt a repair yourself unless you are trained and equipped to do it.

High-voltage safety. This is an electric vehicle. Its high-voltage system can cause fatal injury. Never open, disconnect, cut or work on high-voltage components, cables or connectors unless you are qualified to do so, and always follow the manufacturer's own safety procedure.

Vehicles differ. Equipment, hardware versions and part numbers change between model years, markets and individual VINs. Confirm what applies to your vehicle before ordering or repairing anything. The manufacturer's documentation is the authoritative source for your car — where anything here differs from it, follow the manufacturer.

Consumables and specifications change without notice. Torque figures, fluids and procedures given here are for orientation only.

No liability. This information is published in good faith and to the best of our knowledge, but we accept no liability for any loss, damage or injury arising from reliance on it. Use it at your own risk, and verify anything safety-critical before you rely on it.

Who we are. GNSGO is an independent supplier of parts. We are not affiliated with, endorsed by, sponsored by or acting as an authorised agent of any vehicle manufacturer. References to a vehicle or model describe compatibility only.

10. Related

Need a part for this? Send the VIN and we will confirm the version that fits — get in touch.