Chevrolet Repair Questions? Ask a Mechanic for Answers ASAP
Hello, with this message coming on, the vehicle has entered a load shed level 2. do you have any other problems, battery going dead? wont start? and other warning messages or lights coming on?
I would have the battery tested, to see if it will pass a loadtest. if the battery is good, have the alt check just to be sure. the alt can still have a low output, causing this to happen. if both these items are good, see a few problems just with dirty battery cable connections or bad ground from battery to body and engine. and the last thing we have seen is a problem with the body control module, which is rare but does happens. if all the above check ok, the body control module will need to be scanned for codes. my money is just a bad battery
here is a outline on how the system operates, the message cant be turned off, the message will go out on its own, once the problem has been corrected
The electrical power management (EPM) system is designed to monitor and control the charging system and send diagnostic messages to alert the driver of possible problems with the battery and generator. This EPM system primarily utilizes existing on-board computer capability to maximize the effectiveness of the generator, to manage the load, improve battery state-of-charge (SOC) and life, and minimize the system's impact on fuel economy. The EPM system performs 3 functions:
The battery's condition is estimated during key-off and during key-on. During key-off the SOC of the battery is determined by measuring the open-circuit voltage. The SOC is a function of the acid concentration and the internal resistance of the battery, and is estimated by reading the battery open circuit voltage when the battery has been at rest for several hours.
The SOC can be used as a diagnostic tool to tell the customer or the dealer the condition of the battery. Throughout key-on, the algorithm continuously estimates SOC based on adjusted net amp hours, battery capacity, initial SOC, and temperature.
While running, the battery's degree of discharge is primarily determined by a battery current sensor, which is integrated to obtain net amp hours.
In addition, the EPM function is designed to perform regulated voltage control (RVC) to improve battery SOC, battery life, and fuel economy. This is accomplished by using knowledge of the battery's SOC and temperature to set the charging voltage to an optimum battery voltage level for recharging without detriment to battery life.