Hi I just fixed a 420 code and all the monitors read ok. If I use a scanner or pull the battery to turn the engine light off I will have to go through another drive cycle

Thx

 

How did you fix the P0420 code?

 

if the code is truly gone, driving it will turn the light off. otherwise just reset it and do drive cycle to make it ready.

 

Unfortunately it's not registered because it won't pass the smog, and it still
won't with the engine light on, so I can only get 2 day waivers to drive it, I have no option but to do this with the light on.

My 89 Toyota cleared the light by pulling one of the fuses for a few mins. But just wanted to know if anyone new for sure.

420 code was a cracked pcv hose, I think it was a 420, it was a code for a small leak in the evap system.

 

P0420 is not an evap code.

 

p0420/p0430 is for a cat problem. ask me how i know...

anyway, try starting it a few times and shutting it down a few times (not rapidly, let the engine run a few minutes each time). let it get up to temp as well. Honestly, if its actually fixed, its my impression the computer will turn off the light if the fault is no longer present. however, I know of no way to remove the MIL without resetting the whole computer (battery disconnect or OBD reset through scanner). It should clear by itself if the issue is fixed.

 

Ok it was a 442 code the 420 was my Tacoma.


The original question was if there was another way to turn the engine light off.

IF not Is it better to turn the engine light off by disconnecting the battery or by the scanner, or does it matter . I'm trying to keep the monitors in the ok state, to avoid driving it to far to go through the drive cycle, seeing that its not registered. I have a moving permit but that will only let me drive it to deal with the smog.


Ok I did not see the last post so my question was answered , thx for the help!