Adaptive switch contamination compensation

An adaptive switch contamination compensation system for compensating for contamination of a switch or a switch load circuit connected to said switch in a switch circuit, comprising:

• an A/D converter having an input receiving analog on/off signal levels of said switch, and providing corresponding on/off digital signal levels to a microcontroller;
• said microcontroller having an output providing a polling signal for repeatedly turning said switch on and off in said switch circuit;
• and
• said microcontroller comparing said on/off digital signal levels each time said switch is polled by said polling signals to determine if the on digital signal level differs from the off digital signal level by more than a defined amount indicating that the switch or switch load circuit has been unacceptably contaminated, and said microcontroller outputting a switch or switch load circuit contamination indication output signal to said switch circuit based on said comparison permitting said switch circuit to continue operation or to take action when the switch or switch load circuit has been determined to be unacceptably contaminated.

A method for compensating for contamination of a switch or a switch load circuit connected to said switch in a switch circuit, comprising the steps of:

• obtaining on/off signal levels corresponding to on/off states of said switch in said switch circuit based on a polling signal which turns said switch on and off;
• with each polling signal, comparing the on signal level with the off signal level to determine whether the signal levels differ by more than a defined amount indicating unacceptable switch or switch load circuit contamination;
• and
• based on said comparison, providing a switch or switch load circuit contamination indication output signal indicating whether or not the switch or the switch load circuit has been unacceptably contaminated for use by said switch circuit for continued operation of said switch circuit or for taking a corrective action if unacceptable switch or switch load circuit contamination is determined.