Thread: clear codes

Or...you can pull the PCM fuse and put it back. But to answer your question 30min.

If you had my LS1m Toasty, you could clear that way

LOL sorry brother, it was to easy to pass up

I agree with the above, 30 minutes to an hour is what I have done before to clear codes. Just be aware of what the code might be, you dont wanna go blowing anything up ya know

Can all codes be cleared by disconnecting the battery?

Originally Posted by Toasty

hahahaha yer sooo funny

my LS1m parts are on the way. should be a fun assembly project

perhaps i even will save $$ vs what you paid :P

You know I had to poke a little jab in there my friend

Good luck on the project. If you have any questions or need to take any photos of mine for ya? Please let me know. I will be more than glad to help ya with as best I can.

Originally Posted by archemedes

I have had a pcm in my garage with a missfire code for 2 years now, plugged it in, and the code is still there

Are you kidding? What in the world is the PCM using to power memory storage for that long? How is it doing that?

must be storing that in the non-volatile memory. This is why I ask about clode clealring as I've had a battery disconnected for days and the code that was there stayed.

Well crap, I had no idea. That sucks. So now how is anyone to clear the code if they do not have access to a scan tool or someone that does?

Originally Posted by Toasty

just to add to the info, here's the things that i tried to clear out the P0171 code:

all of these did not work---

disconnect postive and negative... off 1.5 hours
disconnect only positive, less than 10 min.
disconnect positive, unplug PCM fuse.

today, i ran the car back over to advance auto, had them run the codes again. still the P0171 code, but it's a stored code, not a pending (current) code anymore. I think PENDING codes may clear with battery disconnect, not stored. So i asked him to clear it out. (this is just between you and me he says, lol) the code hasnt come back, so appears problem fixed.

I had that same code before. It read that bank 1 sensor was the problem. IE an O2 Sensor. At least that is what the Autozone computer said. I thought maybe I hit the rear sensor at the top of the DP when I was changing out factory spark plug wires.

So I went back in and disconnected the battery the following the morning and left it offline for almost 2 hours and came back and rechecked all connections, even the O2 Sensor and then reconnected the Power to the battery and the code was cleared. Hadnt come back since.

Glitch or not? Not sure cause if it was truly a bad sensor it would have kept coming back.

That is correct, stored codes I do believe will not clear. Active ones will. However, pending codes dont trip the SES light.

disconnecting the battery will not work the last year of vehicle that will work on is is 97' so the only other way to erase the code is with a code reader.

How in the world is a 'pending' code an active code. That defies the very definition of the word.

Originally Posted by Toasty

if pending code meant what you'd think of 'pending' ... our cars would be psychic!

Not really. Pending codes were set when the system ran a test or detected something was wrong and it would set it as a pending code until it occurred over so many driving cycles then it would become the active code and trip the SES light.

There are many of the codes that take, an infraction if you will, to occur over so many driving cycles before the SES light comes on. Others will set the SES light immediately.

I can see it being called a stored code if it has not tripped the SES light, but an active code is not a pending code.