Can't get iMac G3 to boot anything

[LarBob]

I took my iMac G3 out and it boots up to a blinking folder, but it won't boot anything. If I try to boot any CD I get a DEFAULT CATCH code 70, and it won't boot off of the disk either. I used my G5 and Target Disk Mode to install Tiger on the machine but it won't boot from that or find it in the option-key startup menu. I'm able to get directory listings off of CDs and the drive, but not boot into anything.

It has a fresh PRAM battery and I've reset the PRAM multiple times.

 

[LarBob]

I got it to boot with this: https://www.macintoshrepository.org/23373-mac-os-9-2-2-boot-kit-for-booting-your-g3-g4-from-an-usb-stick

The CD-ROM drive and hard drive are working perfectly fine. I installed OS 9.2.2 off of a CD while booted off of USB and the machine is working perfectly now. Weird.

 

[jamie marchant]

You might want to run Apple's diagnostics(to make sure it's indeed working), you need the right one for your machine, some of them are hard to find: https://macintoshgarden.org/apps/apple-hardware-test-cds