Code 43 - Electronic Spark Control (ECS): Notes

Code 43 indicates the ECM has seen high or low voltage at circuit No. 496 for longer than 5 seconds with the engine running.

1. If conditions for test as described above are being met, Code 43 will currently set and the "SES" light will be illuminated.
2. The ECM has a 5-volt pull-up resistor, which should be present at the knock sensor terminal.
3. This test determines if internal resistance of knock sensor is within an acceptable range.