SAAB WIS ONLINE

DTC U2103

DTC U2103

Diagnostic Instructions


• Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• Diagnostic Procedure Instructions provides an overview of each diagnostic category.


DTC Descriptor

DTC U2103 00

Fewer Controllers On Than Programmed

Circuit Description

Modules connected to the GMLAN serial data circuits monitor for serial data communications during normal vehicle operation. Operating information and commands are exchanged among the modules. The modules have programmed information about what messages are needed to be exchanged on the serial data circuits, for each virtual network. The messages are also supervised and some periodic messages are used by the receiver module as an availability indication of the transmitter module.

DTC U2103 is generated if fewer modules are detected in the bus before the modules can learn the ID number of the other module. If the communication bus is activated, or if the power supply to the module disappears when the car's electrical system is switched off and then connected, U2103 will be generated in certain modules.

Conditions for Running the DTCs


• Voltage supplied to the modules is in the normal operating voltage range.

• The vehicle power mode requires serial data communication to occur.

• The DTC U2100 does not have a current status.


Conditions for Setting the DTC

A supervised periodic message that includes the transmitter module availability has not been received.

Action Taken When the DTC Sets

The module uses a default value for the missing parameter.

Conditions for Clearing the DTC


• A current DTC clears when the malfunction is no longer present.

• A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.


Diagnostic Aids


• Diagnosis of this DTC is accomplished via the symptom or an additional DTC. Refer to Symptoms - Data Communications or DTC U0100-U02FF .

• An intermittent condition is likely to be caused by a short on the GMLAN serial data circuits. Use the DTC U0100-U02FF procedure in order to isolate an intermittent condition.