I'm not going to sugarcoat it — I failed the CED twice before finally passing last month. The first time I went in way underprepared, figured my field experience would carry me. It didn't. The second time I used some random study guide I found online that turned out to be completely outdated. Third attempt I actually got serious.
What made the difference was treating it like a real exam campaign. I spent about 6 weeks, roughly 90 minutes a night, working through a CED practice test every few days and reviewing whatever I got wrong. That repetition is what finally got the content retention to stick. The electrical systems and energy auditing sections are no joke — don't sleep on those.
If you're studying right now, my biggest CED exam tip is to not just memorize answers. Understand the reasoning behind each one. The real exam loves to reframe questions so you can't just pattern-match. Anyone else here been through this? Happy to answer questions about what I ran into.