While fording a river with the 2022 HUMMER EV pickup (Fig. 11), an excessive amount of water may slow or stop the cooling fan from spinning, which may cause DTC P0494 (Cooling Fan Speed Too Low) to set in the Battery Energy Control Module. A Service High Voltage System message may be displayed on the instrument cluster along with an illuminated Service Vehicle Soon MIL.
These conditions do not require replacement of the cooling fan motor or indicate an issue with the high-voltage battery system. After a key cycle or during the same key cycle, if the cooling fan is commanded on again, the condition will no longer be present since the cooling fan should operate properly without the presence of water.
Fig. 11
To verify fan operation, command the fan on using GDS2. The air conditioning condenser, cooling fan and radiator are an assembly at the front of the vehicle. (Fig. 12) If the fan operates normally, clear the DTC. Do not replace any parts for this condition.
Fig. 12
Refer to #PIT5925 for additional information.
– Thanks to Paul Radzwilowicz
