ERJ-175 Captain reported multiple EICAS messages displaying during take off. Flight crew aborted take-off and returned to the gate.

Narrative

Our report time was XA:30. The aircraft was dark; I turned the batteries on. In less than a minute; maintenance comes up and tells us the plane shouldn't be on; they are working on it; so they turned it back off. We didn't know the plane was out of service. To my knowledge; they were servicing a firex bottle. 30 minutes later; maintenance was done; they came up and turned the plane on. As we are setting up the flight deck; our EICAS filled up with all caution messages and aural. Batteries were on and APU was on. No reason for those messages to populate. I thought it was maybe a glitch from the ground crew disconnecting the ground power. Once we were fully boarded and ready to close doors; it did it again. It kicked off the auto brake and all bells and whistles came on. We called maintenance; and the reason they gave us was because it was cold that morning; the aircraft doesn't like cold; probably moisture. They performed a few checks; a reset; etc and cleared the write up. Since the plane was turned off and back on again; we reentered the flight plan and set up for the flight. We taxied from the gate to RWY XX and were cleared for take off. During the take off roll; at around 50-70knts; it happened again. Caution followed by about 4-5 EICAS caution messages. Also my PFD (Primary Flight Display) showed a red X on my speed indicator that came and left very quick. As all of this is happening; I'm calling ABORT; ABORT; I communicated with tower that we are aborting the take off and went to the PA and said REMAIN SEATED; REMAIN SEATED. It was hard for me to pinpoint exactly what those messages were and if any other occurrence happened. Not sure if the auto brake was kicked off by the fault or by my student applying braking. As the airplane continued to slow down; more messages started populating the EICAS until it looked exactly the same as the previous 2 times at the gate. All EICAS messages pop up; they all start clearing up slowly until the AP (Autopilot) FAIL remains; then turns into AP FAULT and all is cleared after that. I was with operations and dispatch when tower asked for the reason for the aborted take off; My student handled that and he said something similar but not as specific. I believe he said We had EICAS messages". I should've asked for the tower's phone number and call but I was busy and didn't think of it until now. We returned to the gate and added 2 write ups in the AML (Aircraft Maintenance Logbook). One for the fault and the other for the aborted take off. Maintenance said this time the plane will take a long time to fix; they were waiting on parts coming on another flight and also had to upload the software that would take up to 5hrs. We went back to the hotel at around XB:30. At around XC:45; dispatch calls me and gives me a heads up that the plane is cleared; to please head back to the airport. I called maintenance myself to verify; it was cleared and green. We arrived to the airport; maintenance had added new cards to the module. We commenced to board and to prepare the flight. Once we were almost ready to go; went to do a walk around. On my way back; my student says we are not going anywhere; it did it again. I personally didn't see it this time but as we were deplaning the last passengers; it did it again. We called maintenance and wrote it up again."