Diagnostic Aids

WARNING: This page is about a different car, the 2023 GMC Savana 3500, 2023 GMC Savana 2500, 2023 Chevrolet Express 3500, and 2023 Chevrolet Express 2500. However, it is still accessible from the selected car via links, so may be relevant.

Before beginning any programming first determine which Generation of the K73 Telematics Communication Interface Control Module you are working with. One way to accomplish this is by using a scan tool. The K73 Telematics Communication Interface Control Module Generation will be listed under the Selected Vehicle Configuration section, in addition the Generation (9 or 10) can be determined from the Module ID data table. Additional programming steps may be necessary depending on the generation of the module.
It is critical to use the service replacement Communication Interface Module only in the vehicle for which it was ordered.
Failure to perform the following procedures will result in a red LED, DTC(s) being set, and limited or incomplete OnStar® services.
An OnStar® button press to the OnStar® call center is required to complete the procedure. During this activation call WiFi will automatically be enabled.
To fully activate an OnStar® module, both the setup and activation request procedures must be completed on all vehicles with and without an active OnStar® subscription to insure the unit has been setup properly for the vehicle it has been installed into and also to update the OnStar® with the correct unit information.
To initialize the Turn-by-Turn feature, the vehicle must first be driven In open sky condition at speeds greater than 10 mph (16 kph) or more for a minimum of 5 miles (8 km), and perform at least 2 left and 2 right 90 degree turns coming to complete stops prior to each turn.
On vehicles up fitted with TTY capabilities, it is necessary to perform a power cycle of the OnStar® Interface Module (OTIM), and toggle the TTY mode after completing the Communication Interface Module installation and setup procedures.