Fan goes at high speed, computer pendles two correction pictures
Have just replaced the PRAM battery. Two mistakes during the job. First the optical drive thermal sensor socket came loose in stage 15. second, I discovered I had a CR2032 battery and not a BR2032 but changed the battery anyway.
Tried gluing the socket back to the logic board, which looked as though it was successful.
However, when restarting the machine, the fan starts hissing and there is a noticeable draught from the opening. The machine appears to start to the rotating lines, but instead of booting two pictures start to oscilate.
One shows an oval shape with a rectangle inside. At the top right is another small oval which is the focus of an enlargement and indicates that a switch should be moved up
The other shows an inclined plane with a cylinder at the right, and on the cylinder end is an on-off switch which is indicated by an arrow.
Any ideas welcome. I'm going to open up the computer again and see if there is anything obvious, but I wonder if the loose socket is not sitting perfectly and the fan is trying to cool the optical drive.