Well, you learn something every day and sometimes you even get lucky. My neighbor had his CEL on in his '03 Ex and wanted to know why. I told him to stop by and I will use my AE to check codes. After connecting, we retrieved the codes for the engine and his backup sensors. I was impressed that the codes came up indicating exactly which backup sensors had a fault. Also, turned out that his ICP must have spiked when he was on it hard because the freeze frame showed 2575 rpm at 64 mph. Just to show him what the AE would do, I started the engine to show how it can display real time activity. Then, while it was running, I cleared the codes and the engine died! Tried to start but wouldn't quite go. Reset his DP tuner to stock but still no go. Changed it back to the original setting and finally got it fired but there was no throttle response. Finally shut the engine off, disconnected the AE, restarted the engine and everything was fine. Then, after re-reading the AE manual, I learned what clearing the codes does include resetting the fuel trim stored values which is probably why it died and wouldn't restart without turning the key off. No where did the manual say to be sure that the engine is off before clearing codes but you can be sure that it will be whenever I use the AE again. I thought that I would pass this on so others wouldn't have the same scare that I had.

 

Thanks for the tip. I will be sure to remember that. I bet it would scare yea, thinking "what did i do?"

 

Especially with the neighbor standing right there. At least he wasn't too concerned.

I was wondering what procedures others follow when they clear codes? The manual wasn't very clear about that.

 

I would normally just plug in pc. Turn on key pull up codes if any. if so , write them down. Clear them. All without starting. Never tried to clear codes while it was running.