Some 2021-2023 Tahoe, Suburban, Yukon and Escalade models equipped with the air leveling suspension (RPO F47) may have a low or leaning suspension or the air leveling function may be inoperative. (Fig. 3) A Service Leveling System message also may be displayed on the Driver Information Center.
Fig. 3
When checking for DTCs, several DTCs may be set in the Air Leveling Control Module. There also may be DTCs set that do not seem relevant to the air leveling suspension, such as U0222 (Lost Communication with Front Side Door Window Regulator Motor – Driver), U0223 (Lost Communication with Front Side Door Window Regulator Motor – Passenger), U0224 (Lost Communication with Front Side Door Window Regulator Motor – Passenger) or U0225 (Lost Communication with Rear Side Door Window Regulator Motor – Right).
In addition, when using GDS2 to perform the Short Term Inflate function, the function may not work, but the GDS2 screens indicate that it is.
These conditions may be the result of a loss of communication with a power window motor or a door ajar issue. In some cases, these conditions are more typically found on upfitted vehicles. Check for any loss of communication concerns or door ajar DTCs.
For proper operation of the air leveling suspension, the door ajar status must show the doors are closed. Each door ajar switch is hard wired to its door window motor. When there is a DTC set for a loss of communication with a door window motor, the door ajar status (open/closed) will not be reliable and the GDS2 door ajar parameter will default to closed, even though the actual door ajar status is unknown due to the communication issue.
When monitoring the door ajar data, open and close each door to ensure the door position matches the GDS2 parameters. (Fig. 4)
Fig. 4
After any repairs associated with the door ajar DTCs or a loss of communication with a door window motor, reevaluate the air suspension operation.
– Thanks to Jim Will
