U2101 - FAULT CODE - OBD2

U2101 CHEVROLET - MAXIMUM LIST OF CAN CONTROL MODULES NOT PROGRAMMED

Control modules that connect to serial data circuits via the high-speed and low-speed GMLAN (Engine General Local Area Network) have constant monitoring of serial data communication during normal operation of the car. The modules exchange operating information and commands, and although they have pre-recorded information about the messages they need to exchange on the circuits for each virtual network, these messages are monitored. In addition, some periodic messages are used by the receiving module as an indication of the availability of the transmitting module. In each of these messages, the identification number of the transmitting module is sent.

The U2101 OBDII fault code is set on Chevrolet vehicles when the subnetwork configuration is not programmed or there are less than two modes programmed.

• Check Engine lamp comes on.

The reasons why the U2101 OBD2 diagnostic code is set in your Chevrolet vehicle are as follows:

• Bad wiring or system connectors may be present.
• Engine General Local Area Network electrical connections may be faulty.
• A control module may be damaged.

The steps to follow to correct the DTC U2101 OBDII code on your Chevrolet are:

• As a first step, consult the Technical Service Bulletins.
• Use an automotive scan tool and check if other DTCs are stored. If such codes are found, perform repairs to the codes in the order shown on the scanner.
• Inspect the condition of all GMLAN wiring and connectors. Repairs or replaces any burned wires or corroded connectors.
• Perform voltage checks on the circuitry related to the system and verify that all of these results match those specified by the manufacturer. If deficiencies are discovered, make the appropriate repairs.