U0026 - CONTROLLER AREA NETWORK (CAN) DATA BUS: LOW-SPEED BUS (-) - VOLTAGE HIGH
POST UPDATED IN January, 2023
Description of DTC code U0026 Generic
In the CAN bus or Control Area Network, several controllers are interconnected. They are responsible for transmitting commands through this circuit and operating parameters of the car. The control modules have pre-stored data, which is closely related to the messages needed to be exchanged between serial data circuits.
The Control Area Network uses two dedicated wires to complete the communication. These wires are known as CAN high and CAN low, which carry 2.5 V while the circuit is inactive. During the activation of the bus from the high line, it has 3.75V. The low line decreases to 1.25 volts, maintaining between the two lines 2.5V.
When the diagnostic code U0026 OBDII is set, it means that the low-speed bus has experienced voltages that exceed the range set by the manufacture. So it causes a high voltage condition.