Hi,

I'm running an imported 2001 Japanese Hiace Super Custom 2.4l petrol (2RZ-E engine). This doesn't have a OBD2 port - only the Toyota ODB1 / DCL1 port. The engine management light is NOT on but I connected the TE1 and E1 to get any flash codes. I got '21' - which I believe is oxygen sensor. I've done some reading and I came across something that said the computer will store a 21 error without putting the engine management light on - but will light it is it receives a second 21 on a later drive.

I know the battery was replaced a month ago - so I assume the error was picked up since then. I thought it's reset it and see if it reoccurs. I've tried both disconnecting the EFI fuse for 30+ secs and also the vehicle's battery - but the error reoccurs immediately. I can't get rid of 21 flashing up on the dash.

Could this mean the oxygen sensor is kaput or it's connection is effectively cut? But wouldn't this eventually bring up the engine light on the dash?

Any thoughts welcome