Code 43, Knock Sensor Without Spark Module (Single Sensor): Notes

NOTE: Test numbers refer to test numbers on diagnostic chart.

Code 43 will set when vehicle reaches normal operating temperature (but not overheating), high engine load is indicated by MAP sensor and voltage on sensor signal circuit is greater than 3.5 volts DC or less than 1.5 volts DC. This step determines if system is functioning properly at current time.
This step determines state of 5-volt reference signal applied to sensor.
Checks knock sensor internal resistance.