Pular para o conteúdo

U0200 Baixa Genérico / SAE

U0200: Perda de comunicação com o módulo B de controle da porta

WhatsApp Telegram X E-mail

O que fazer

The car drives normally. What you will notice is one door misbehaving — its window, mirror or lock not working, or working only from its own switches rather than from the driver's panel.

Before anything is replaced, three things are worth saying, because they cover most of these faults and cost nothing to check.

  • Has any water been in the car? A blocked door drain, a torn plastic sheet inside the door, a leaking windscreen or sunroof seal, or a drink spilt in a footwell will all do this. These modules live inside doors and under seats, which are the two wettest places in a vehicle, and a damp connector stops working long before anything looks damaged.
  • Does it change when the door is opened or closed? The wiring crosses from the body into the door through a rubber concertina, and it bends every time the door moves — tens of thousands of times. Broken wires in there are the classic fault, and a problem that comes and goes with door movement is that until proven otherwise.
  • Are other things on the car also complaining? If several unrelated body systems have gone at once, that is usually one network fault rather than several failures, and it points somewhere completely different.

Do not let the module be replaced first. It is named by the code, but its power supply, its earth, its connector and that door loom are all commoner and far cheaper.

O que este código significa

The second door control module has stopped being heard from on the vehicle's data network.

Everything U0100 says about what a lost communication code means applies here and should be read first — the code names a module and says only that its messages stopped arriving, never that the module has failed. What follows is what makes this block different, because U02xx is not a continuation of U01xx in subject so much as in numbering.

U01xx names the modules that make the car go. U02xx names the modules that make it comfortable. Doors, seats, windows, mirrors, roofs, switches. That single difference changes the diagnosis in three concrete ways, and they are worth having before opening anything.

First, these modules usually live on a different, slower network. Body electronics rarely share the high-speed powertrain bus; they sit on a body CAN, a LIN subnet or a local link, bridged across by a gateway. So a U02xx code normally does not mean the vehicle's main network is in trouble — and the reverse is the more useful inference: a cluster of body codes with no powertrain codes at all points at the gateway or the body bus rather than at any of the modules named.

Second, and this is the dominant cause in the whole block: these modules live where water gets in. A door module sits inside a door, behind a plastic vapour barrier, above drain holes that block with leaf litter. A seat module sits under a seat, in the footwell, under everything that gets spilled. Between a blocked door drain, a torn vapour barrier, a leaking screen or sunroof seal and a spilt drink, water accounts for more body-network faults than every electronic failure combined — and it produces exactly this code, because a wet connector stops carrying a signal long before anything is visibly damaged.

Third, the door harness flexes every single time the door is opened. The loom crosses from the A-pillar into the door through a rubber boot, and it does that tens of thousands of times over a vehicle's life. Conductors inside that boot work-harden and break, and the failure is unmistakable once it is suspected: the fault appears or clears as the door is moved. That is the classic body-network fault and the first place to look on any door-related code.

What "module B" means is simply the second one, and which door it is follows the manufacturer's convention rather than a universal rule — commonly the front passenger door where A is the driver's. Confirm it against the vehicle's own documentation rather than assuming, because on a four-door car with modules A to D the difference decides which door gets stripped.

The consequences are inconvenience rather than danger: that door's window, mirror and lock stop responding, or respond only from their own switch panel. The exception worth knowing is central locking — on vehicles where the door module handles it, a lost module can leave a door that will not unlock with the others.

Causas prováveis

Comece aqui

Menos comum

Sintomas

Componentes envolvidos

Informação, não instrução

O CarGeek é uma referência, não um manual de serviço. Suas páginas são escritas a partir de fontes públicas e do que outras pessoas constataram, nunca a partir da documentação de serviço do fabricante, de modo que podem estar erradas ou incompletas para o seu veículo específico. Parte do que descrevem envolve risco real: alta tensão, combustível sob pressão, energia acumulada e peças quentes ou em movimento.

Antes de agir com base em qualquer orientação, peça a verificação de uma pessoa com formação técnica, seguindo o procedimento do próprio fabricante para o seu veículo. Nada aqui substitui esse procedimento.

Experiência da comunidade

Seja o primeiro a documentar isto

Ainda não há publicações sobre isto. Vale a pena anotar tudo o que você descobriu — até um beco sem saída poupa a mesma tarde de outra pessoa.

O que faz valer a leitura:

  • O carro — marca, modelo, ano e motor. A mesma falha se comporta de forma diferente em cada um.
  • O que você mediu, não só o que trocou.
  • O que realmente resolveu — ou que nada resolveu, o que também vale saber.

Entrar ou criar uma conta para adicionar o que você descobriu sobre U0200.