Meaning of the indication
The current-feedback chain is delivering an abnormal indication to the controller. The diagnostic path begins with the detection and signal-isolation circuit rather than an automatic assumption of power-module failure.
Checking order
- Inspect the control-board current-detection section and the recorded Q1-related circuit area.
- Check the signal-isolation stage associated with the 7840 device using the applicable bench procedure.
- Evaluate the small detection board and related comparator devices when reference measurements are inconsistent.
Suspect areas
Current-sense signal chain7840 isolation deviceDetection sub-boardComparator devices