2019 Nissan Murano

My car wouldn't start one morning. All lights lit up on dash, headlights continually started flashing and fan running under hood. I had to get to work so took a Lyft. I knew older son would be home from firestation around 830. When he got there battery completely dead. He jumped the car started right up. He drove to autozone to have battery checked (about 5 blocks). Battery was fine. He drove home. When I got home car started right up. I started it up again about 5 hours later. Went on my road trip I had planned about 2 hour drive. On Sunday I get in my car to leave and it does same thing it did Friday morning. I had to have car towed back to Nissan dealership in my hometown ( 700.00). Dealership had car for 3 days and came up with ABS module shorting to CAN unit. Only problem is the part is on backorder and Nissan can not even tell me when part will be in. This was almost 3 weeks ago. I have had no car for 3 weeks. I paid 555.00 for diagnostics and they want me to pay to order a part that isn't even available and was told Nissan has no idea when it will be. Why would I give them more money to order a part that is not even available. Is the part not available because this common problem? I do know there was recall on year before mine, 2018, and my car was manufactured 2/2019. My car is now in my driveway sitting, waiting to see if a part becomes available. But I feel this is an ongoing problem with Nissan.

I lost brake pressure at a red light today. I ended up pressing the brake all the way to the floor and kept rolling. The light turned green and I pressed the gas and the brake started working after that and has worked since. I started googling and I saw this was an issue in older Muranos as well. I do not want to take it in and spend a bunch of money on master cylinders, etc when it may not be the issue. Please investigate.