KC Mike

I own a 2008 Lexus RX 350 with about 65,000 miles on it. Three years ago the battery discharged totally and created large amounts of corrosion around the positive battery cable. The damage required the dealer to replace the engine wiring harness. Since this was about a $3,000 repair I was happy that it was covered under the warranty. Now I have the same problem again. This time the dealer thinks we can just replace the positive battery cable. They have no idea what is causing this recurring problem. If anyone has had a similar problem I would appreciate hearing how you resolved it.