Code help B0502, B0507 and P1153 only codes
2002 Z06. I have these three codes and I am struggling with finding the issue. I replaced the O2 sensor. I replaced the burnt sockets on the DRL's. Engine stays in open loop and the dash light flicker unless the relay (do not remember which of the 2 relays I pulled) is pulled, then no front turn signals.
I suspect these are related and there is a short to ground. Can someone suggest the most probably location to begin my search? I do not have access to a lift. I struggle with electrical issues to begin with, but I do have a good DMM and can halfway use it...HAHA. I do have shop manuals.
Thanks for any help you can offer.
Jimmy Carter
Last edited by goatkeeper; Feb 3, 2026 at 10:38 AM. Reason: misspelled word
Last edited by C5 Diag; Feb 4, 2026 at 02:36 PM.
When you choose to live in a rural area, as we do, the options are limited. I'd have to trailer my car an hour and half to a town large enough which might have a component electrical automotive shop.
I've learned in the past, often times forums are a wealth of information. By posting, I hope someone might have had a similar issue and would be willing to share their experiences.










