Battery Drain with no warning lights
I bought an 05 LS Coupe with auto trans and 107K miles about a year-and-a-half ago. It deveIoped a battery drain a couple of months ago. I replaced the front speakers recently (blown). There didn't appear to be any water damage or any other problems with the wiring. The reason I mention the speakers is that the battery drain is less when I pull the RDO 10 amp fuse inside the car. Unfortunately, changing the speakers had no effect on the drain. I checked the drain (draw) with all of the lights off using a digital multimeter. The draw with all fuses in is 1.17 amps. If I remove the RDO 10 amp fuse only, the draw drops to .42 amps. If I remove the BCM2 40 amp fuse only (under the hood), the draw drops to .81 amps. If I remove both fuses the draw drops to zero. If I pull the plug off of the back of the radio it does the same as pulling the RDO fuse. The battery is new and the alternator has been checked twice and checked good. I'm also not sure if the charging system is charging the battery fully. I can drive the car around for an extended period of time and then put the charger on and it draws 5 to 6 amps. I would think the battery should be charged better after driving it that long. It has the newer charging system with the metering device on the negative battery cable. There are no other issues that I know of and the radio and all four speakers work fine now. I know nothing about troubleshooting the charging system. Any help would be greatly appreciated as the next step is to probably take it into a dealership or an auto electric shop. Thanks, Dale
Last edited by reposado; 03-12-2018 at 07:33 AM.