The IOR radio is the mid-level infotainment system fitted to base and work trims of many 2018-2026 GM vehicles. GM’s service literature calls it the “3.0 low HMI, midlevel connectivity radio infotainment system”; in marketing it appears as Chevrolet Infotainment 3 and the GMC Infotainment System.
IOR sits between the basic audio-only systems and the CSM. It runs a home screen that looks very similar to a CSM’s, which is the single most common source of wrong orders. The difference is the App Shop. Every North American CSM has one. IOR does not.
How to identify IOR
Scan the QR code on your driver door or B-pillar to pull up your RPO list, or check the SPID label in the glovebox, and look for the code:
- IOR: this system. Mid-level radio, no App Shop.
- IOS, IOU, IOT: CSM variants. A different module entirely.
- IOK: CSM running Google built-in.
- IOV: CSM specific to the 2021-2024 Escalade.
- IO4, IO5, IO6: the older HMI architecture.
Screen size does not change the receiver
IOR was fitted with either a 7″ display (RPO UIR) or an 8″ display (RPO UIJ). On the standalone applications the receiver part number is identical either way, because the display is a separate component. GM’s own option definition confirms this: UIR is described as a 7″ WVGA 800×480 TFT infotainment display, which is a panel rather than a radio.
Standalone versus all-in-one
IOR appears in two physically different forms.
On trucks, and on the cars and crossovers listed below, the receiver is a standalone module mounted behind the dash, with the display as a separate part.
On the Chevrolet Traverse, and on the 7″ versions of the Chevrolet Trax, Chevrolet Trailblazer, Buick Encore GX and Buick Envista, IOR is a combined screen-and-receiver assembly. Those are not interchangeable with the standalone module. The 8″ versions of the Trax, Trailblazer, Encore GX and Envista use a separate receiver.
SiriusXM changes the part number
Unlike screen size, satellite radio does change which receiver a vehicle needs. Vehicles built with SiriusXM (RPO U2K) take a different part from those built without. A factory-spec replacement has to match the as-built configuration.
Two narrow exceptions add a further split. On the 2019-2020 Camaro and the 2020 Malibu, active noise cancellation (RPO NKC) also changes the part. And GM revised the 2020 Camaro receiver partway through the model year, on 15 February 2020, with the two designs explicitly not interchangeable.
Codes to ignore
Several RPO codes appear alongside IOR in GM catalogues but describe markets rather than hardware, and none apply to North American vehicles: MAM (Middle East), MBI (Israel), MBB (Australia and New Zealand), MAB (China), MAY (Andean and South America), MBH (Southeast Asia) and U2Q (export digital audio broadcasting, which is not SiriusXM).
Replacement
IOR replacement requires VIN programming. Units supplied pre-programmed install plug-and-play after disconnecting the battery, with no dealer visit and no core return.