Check Control Messages Related to Battery Charge During Cold Ambient Temperatures. On cold days with an outside ambient temperature of less than 15F, customers may notice a check control message related to the battery that is displayed on the instrument cluster and the control information display. Under these conditions, the vehicle starts. Various power management faults can be stored: * 213901 - Power management: Reduction or shutdown of individual electrical consumer * 8040BD - Reset or deactivation of Terminal 30F * 8040B9 - De-activation of terminal 30B: Top start capability limit reached * 8020E8 - Reset or deactivation of terminal 30F * 800E89 - FRM: start capability limit reached with lights active during stationary mode * 93076B - Deactivation of terminal 30B: upper start capability limit reached * 93076A - Deactivation of terminal 15: upper start capability limit reached, but deactivation preventer active * 93076C - Deactivation of terminal 30B: upper start capability limit reached, but deactivation preventer or legal loads active * 930769 - Deactivation of terminal 15: upper start capability limit reached Note: When the outside temperatures drop below 46F, the charging system is switch to full charge. CAUSE * The check control message (ID 229) is caused by a heavily discharged battery. * The check control message is triggered when the current state of charge (SoC) of the battery approaches the minimum SoC that is required to start the vehicle (start capability limit). * In low outside ambient temperatures, the start capability limit of the vehicle is higher. Therefore it takes more energy from the battery to start a cold engine. * Without the early warning of the check control message, the current state of charge would drop below the start capability limit and the vehicle would not start. * The vehicle's intelligent power management system actively takes measures to increase the charge of the battery, such as increasing idle speed and reducing or shutting
