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I have 01 Tahoe 5.3 that I have no power at all no headlights no interior lights wipers horn radio dash lights battery is reading 12.4 v any suggestions. I’m thinking bcm but is there a way to test it? Any suggestions would be greatly appreciated
So, I suggest going to your fuse panel and see if power is getting to there. I would assume a large fuse is blown. Use a test light connected to ground and touch the top of each fuse connector, two of them. If a fuse has power on one connector top but not the other, that one is blown.
Are you able to crank the car? What does work? Is there power anywhere? If not, check the negative side of the battery to frame connection.
Thank you and sorry for not being very clear I do have power at the fuse box and also at the alternator. Just nothing inside was working no lights of any kind no dash horn wipers Ect. However I did unplug both terminals on the battery overnight once hook back up got it and it fired right up after the fact I had to cycle key because loosing fuel pressure but that’s another topic.
No fuses are flown, they don't reset after a power disconnect. A blown fuse is a blown fuse.
There might be a relay that is getting stuck.
You might have poor connections to your battery. I suggest ensuring the connectors to the battery are clean and maybe even have some corrosion protection on them.
We need to determine what 'component' reset or received a better connection after playing with the battery. For example, maybe a ground wire somewhere has some broken wire fibers that are not touching not because you moved something around.
Without actually seeing your vehicle, this is what comes to mind and stuff I would look at.
Thanks I will check grounds once problem occurs again... been two days and no problems so fingers crossed I did however clean battery terminals and even cleaned wires on starter
