DTC C056D
Diagnostic Instructions
DTC Descriptor
DTC C056D 00: Electronic Control Unit Hardware
DTC C056D 0F: Electronic Control Unit Hardware Signal Erratic
DTC C056D 18: Electronic Control Unit Hardware Low Signal Amplitude
DTC C056D 31: Electronic Control Unit Hardware Internal Checksum Error
DTC C056D 32: Electronic Control Unit Hardware General Memory Malfunction
DTC C056D 33: Electronic Control Unit Hardware Special Memory Malfunction
DTC C056D 34: Electronic Control Unit Hardware RAM Malfunction
DTC C056D 35: Electronic Control Unit Hardware ROM Malfunction
DTC C056D 36: Electronic Control Unit Hardware EEPROM Performance/Malfunction
DTC C056D 37: Electronic Control Unit Hardware Software Malfunction
DTC C056D 39: Electronic Control Unit Hardware Internal Malfunction
DTC C056D 3A: Electronic Control Unit Hardware Incorrect Component Installed
DTC C056D 3B: Electronic Control Unit Hardware Self-Test Malfunction
DTC C056D 3C: Electronic Control Unit Hardware Internal Communication Malfunction
DTC C056D 43: Electronic Control Unit Hardware EEPROM Incorrect Programming
Circuit/System Description
The internal fault detection is handled inside the control module. The symptom byte listed in the DTC Descriptor is for engineering reference only. No external circuit diagnosis is involved.
Conditions for Running the DTC
The module runs the program to detect an internal fault when power up is commanded. The only requirements are voltage and ground. This program runs even if the voltage is out of the valid operating range.
Conditions for Setting the DTC
The module has detected an internal malfunction.
Action Taken When the DTC Sets
The module refuses all additional inputs.
Conditions for Clearing the DTC
| • | A current DTC clears when the malfunction is no longer present. |
| • | A history DTC clears when the module ignition cycle counter reaches the reset threshold of 50, without a repeat of the malfunction. |
Diagnostic Aids
| • | This DTC may be stored as a history DTC without affecting the operation of the module. |
| • | If stored only as a history DTC and not retrieved as a current DTC, do not replace the module. |
| • | If this DTC is retrieved as both a current and history DTC, replace the module that set the DTC. |
Circuit/System Verification
Verify that DTC C056D is not set.
| ⇒ | If the DTC is set in a control module that can be programmed, program the control module. If the DTC resets, replace the control module that set the DTC. |
| ⇒ | If the DTC is set in a control module that cannot be programmed, replace the control module that set the DTC. |
| ⇒ | If the DTC is set in a sensor, replace the sensor that set the DTC. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
Control Module References for module replacement, programming and setup
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