98 windsar airbag indicator light

My 98 windstar had a bad left front sensor, I changed the sensor but the indicator light still comes on and stays on. When you first start the van it flashes for a while befor it stays on. how can I fix the problem

Its flashing you a two-digit code five times before being steady. What is that code?

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Its flashing you a two-digit code five times before being steady. What is that code?
I have the same problem only it is flashing twice then one, does this mean 21? what does this tell me? Thank you.