Feedback wire shorted to a voltage supply or damaged insulation; Corroded, loose or pushed-back pins in the connector for the affected module or its feedback circuit; Low battery voltage or poor charging causing unstable module supply and false circuit readings; Fault in the module or device that drives the disable feedback signal; Internal fault in the control module that logged the code; Outdated module software where the manufacturer has identified it as a cause of this code; Water ingress or previous repair or accident damage affecting the harness.

U302A

Control Module A Disable Feedback Circuit High.

Generic
Network
Generic code
Medium severity

How this code is built

U: SystemNetwork
3: Defined bySAE, the same on every car
0: AreaNetwork area 0
2A: FaultThe specific fault in that area

What it means

U302A is a generic communication-class code meaning Control Module A Disable Feedback Circuit High. The control unit monitors a feedback line that confirms whether a module or output has been disabled, and it saw that line sitting at a high voltage when it expected a different state. Which module is 'A' and what it disables depends on the make, model and engine, so check the manufacturer wiring information.

Symptoms

Warning light on, which could be the engine, ABS, airbag or a general fault light depending on the module concerned
Related system limited or switched off, such as a reduced-power mode or a disabled output
Other modules logging communication or related fault codes at the same time
Intermittent or no operation of the function controlled by the affected module
Car may fail to start or may start and then stall, but only on some designs

Possible causes

Feedback wire shorted to a voltage supply or damaged insulationlikely
Corroded, loose or pushed-back pins in the connector for the affected module or its feedback circuitlikely
Low battery voltage or poor charging causing unstable module supply and false circuit readingspossible
Fault in the module or device that drives the disable feedback signalpossible
Internal fault in the control module that logged the codepossible
Outdated module software where the manufacturer has identified it as a cause of this coderare
Water ingress or previous repair or accident damage affecting the harnessrare

How to diagnose

Scan all modules, record every stored and pending code, and read the freeze frame data to see when the fault set
Check battery condition and charging voltage, as low voltage can set circuit codes and cause communication faults
Use the manufacturer wiring diagram for the specific model to identify which module is 'A' and where the disable feedback circuit runs
Visually inspect the related harness and connectors for chafing, water, corrosion, heat damage and previous repair work
Check the module power and earth connections for good voltage and low resistance
With the key on, measure the voltage on the feedback circuit and compare it with the manufacturer's expected value for the disabled and enabled states
With the circuit disconnected at the module, test for a short to voltage on the feedback wire
Check for manufacturer service bulletins or software updates relating to this code on the model

How to fix

Repair or replace damaged wiring that is shorted to voltage, using proper terminals and sealing
Clean, repair or replace corroded or loose connector terminals and secure the connectors
Restore proper battery and charging system condition if voltage was low or unstable
Repair or replace the device or module that supplies the disable feedback signal if it tests faulty
Replace and programme the affected control module only after wiring and supply have been proven good
Apply a manufacturer-released software update if a bulletin links it to this code

Can I keep driving?

Medium severity

The car may be drivable, but the affected system could be disabled or limited and the fault may get worse, so have it diagnosed soon. If a safety system such as braking, steering or airbags is affected, or the car is running poorly, limit driving until it is checked.

Guide written by AI from the code's definition. Confirm with a diagnosis before replacing parts.