Buick Repair Questions? Ask a Mechanic for Answers ASAP
Hello, my name is Bobby. Thank you for the question. The battery needs to be load tested first. If the battery has an internal short this will occur even though the charger may show that it is at 100%. If the battery is fine then most of the time this is caused by a failing ignition switch. The ignition switch is a very common failure on this vehicle. I would fully test the battery first though. Let me know if you need more help.
Thanks for the description. It does sound like the ignition switch. It can be the body control module but that is not as common.
The ignition switch on this vehicle sends an on signal to several circuits which can result in different modules turning circuits on and off. From the wide variation of issues I would lean more towards an issue with the body control module though. I would even check the negative battery cable ground connections as they can cause a serious of random electrical problems.