I have a 2010 Rav4 sport with around 45k miles on it that is exhibiting intermittent no crank no start and the horn honking randomly when the car is off. Below are more details including recent services performed on the car:
Monday 1/2: Firestone wheel alignment
Monday 1/2: AAA test battery and starter (bad battery & good starter), replace battery
Saturday 1/7: Toyota Dealership Power Window Master Switch (PWMS) recall, Wiper Motor Link Corrosion recall, Rear Outboard Seatbelts recall, address TPMS light, top-up engine coolant
On Sunday 1/8, I drove the car in the morning with no issues. In the evening, I mounted a new dash camera and plugged it into the 12V socket near the cup holders. I went to start the car and it would not crank, only making a single click sound. Several lights on the dash light up (battery, power steering, etc). My headlights seem to have full power and do not fade when turning the key. I unplugged the dash camera, and tried to start it again again with the same results (no crank, single click). I also tried shifting in and out of drive and neutral with the same result (no crank, single click). Then I tried to jump the car with the same no crank result except now it didn’t even make the single click sound.
I parked the car to leave it alone since I am traveling out of town this week. That evening, the car’s horn started going off intermittently every 3-8 hours in 10-50 second bursts. I didn’t know it was my car since it is parked in a garage with many other cars. On Tuesday, my girlfriend tried to start the car and it started without any problems. She drove it around for 20 minutes and then parked it, she immediately tried to start it again after parking it and it once again exhibited the no crank condition. She heard it honk after she turned it off. She checked to make sure the horn wasn’t sticking and I walked her through pulling the horn fuse - she was very frustrated at not being able to find fuse #10A
I realize some details but may be irrelevant but wanted to include them just in case. I appreciate any guidance you can provide on how to track down this issue. I really doubt that the dash cam would have shorted something (wouldn’t the cigarette lighter fuse have blown first) but it seems like the issues started after trying to install it. The horn issues also started after trying to jump the car so that could have been the cause instead? I will likely drive/tow (depending on if it starts) it to either Toyota or Firestone once I'm back but would like to try to narrow down the issue myself especially if it is something small like a relay.