Problem with the SRS. Not a DIY repair. Take it to a professional. There may be a problem with your airbag system if the light is staying on. Take to a qualified technician or your dealership for diagnosis.
For the airbag light to turn off, you'll need to repair the cause of the airbag malfunction, or disable the airbag by using a BMW scan tool or other software.
Once you have repaired the cause of the light, it will reset itself.Once you have repaired the cause of the light, it will reset itself.
I suspect multiple problems. The blank or intermittent odometer problem is a common problem in the 2002 Ford Explorer. The ABS and airbag lights are most likely a different problem than the odometer problem. For complete information on the intermittent odometer problem, see http://www.odometer-repair.com .
Code 21 indicates ECT out of self-test range
Take it to a professional. Repairing an SRS is not a DIY job. If the seats have been replaced, and it is an airbag light that is from the chair, and the new chair does not have one, then a connector can be joined which tells the car its plugged into one, (a dummy air bag if you were) and the light stops. I have done something similar on my 306.
The airbag light stays on when the computer detects a malfunction and sets a code. The fault needs repaired and the light will shut itself off.
You would have to take it to a Ford dealership so they could diagnose why the airbag light is on. It is not something that you would want to do yourself.
The airbag computer has detected a malfunction and set a code. You need to take it in for service with a trained technician. The airbag system is not the place for do it yourselfers.
This airbag issue is part of a recall by Mazda. You should contact your dealer.
I found that urinating on the passenger seat works well. You can also try inserting your phallus into the cigarette lighter to cause a short.
Most likely it a broken or malfunctioning clock spring in your steering column
Usually an airbag light blinks to signal a problem. The number of blinks tells the driver the code number, which informs the driver of the problem.