U0002 - CONTROLLER AREA NETWORK (CAN) DATA BUS: HIGH SPEED BUS - PERFORMANCE PROBLEM/ CONFIGURATION ERROR

The control modules that are connected to the Controller Area Network (CAN) circuits monitor frequently the serial data communication during the car performance. They send several commands and working information to each other.

The control modules have pre-recorded information about the messages that need to be exchanged in the serial data circuits for each virtual network. These messages are monitored, as well as some messages. They are used by the receiving module as an indication of the availability of the transmission module. The monitoring timeout is 250 ms. Each of these messages contains the identification number of the transmitter module.

This code U0002 OBDII DTC is set when a supervised periodic message is not received, which includes the availability of the transmitter module

• Check Engine lamp illuminated.
• Difficulty starting the vehicle.
• The engine may shut down unexpectedly.

Reasons to set the U0002 OBD2 fault code:

• Shortages in the CAN bus wiring or connectors.
• Faults in the battery. Thus, it causes a low voltage condition.
• A control module could be damaged.

When the U0002 OBDII diagnostic code is set, consider this:

• Locate the vehicle's information source to access the TSBs.
• Use a scan tool to communicate with the modules. Verify if the DTC U0100-U0299 or U2105-U2199 codes are stored as current. If you discover one of the above codes, perform the respective diagnosis.
• Check if there is at least 5 Ω between the ground circuit and the applicable module. If the resistance is higher than indicated, check to rule out an open resistance.
• Verify that the circuits of the module you are applying are working properly. If you discover a high resistance, a short to ground or fuse, there may be any damage.
• If all the circuits are performing right, it is indicative of a bad module. Replace it.