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Code 43, ESC Error V8 With ESC Module: Notes

  1. If conditions for a Code 43 exist, "Scan" tester will indicate knock signal presence. There should not be a knock signal at idle unless an internal or system problem exists.
  2. Determines if system is functioning at this time. Usually, a knock signal can be generated by tapping on the exhaust manifold. If no knock signal is generated, try tapping on engine block closer to sensor.
  3. Because Code 43 sets when the signal voltage on the spark retard line remains low, this test should cause the signal on that line to go high. The 12-volt signal should be seen by the control module as a "no knock" signal if the control module and wiring are okay.
  4. This test will determine if the knock signal is being detected on the sensor-to-controller line or if the ESC module is at fault.
  5. If sensor line is routed too close to secondary ignition wires, the ESC module may see induced interference as a knock signal.
  6. This checks ground circuit to module. An open ground will cause the voltage on the monitored line to constantly remain about 12 volts. This would cause the Code 43 functional test to fail.
  7. Contacting the sensor-to-controller wire with a test light connected to 12 volts will generate a knock signal to the controller. This will determine if the ESC controller is operating correctly.
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