Polar Refrigerator Error Code HI dc

The HI dc code on a Polar N7LX or N8LX refrigerator means the DC input voltage coming into the unit is too high. These models require a stable 12.0 VDC supply, and the control system trips this fault when it detects voltage above that level. The fault is a protective measure to prevent damage to internal electronics. Correcting the power source voltage is required to clear the condition.

No, you should not continue operating the refrigerator while the HI dc error is active. Sustained over-voltage can damage the control board, compressor driver circuitry, and other sensitive components. The unit is designed to stop operating under this condition precisely to avoid that damage. Resolve the voltage issue at the source before restarting.

If the problem is simply an incorrectly set power supply or a wiring connection issue, the fix may cost little to nothing. If the over-voltage has damaged internal components such as the control board, repair costs could range from around 80 to several hundred dollars depending on parts and labor. Having a vehicle's alternator or voltage regulator repaired or replaced typically costs between 150 and 400 dollars or more. Diagnosing and correcting the power source first is the most cost-effective approach.

Use a multimeter to measure the DC voltage at the refrigerator's power input and confirm it reads 12.0 VDC. If the voltage is higher, trace the issue back to the power source, which could be a vehicle alternator, a DC power supply, or a solar charge controller. Adjust or repair the power source until the output is stable at 12.0 VDC, then restart the refrigerator.

Simply resetting the unit will not permanently clear the HI dc error if the input voltage is still too high. The fault will return as soon as the refrigerator detects the over-voltage condition again. The root cause, which is the elevated DC supply voltage, must be corrected first. Once the input is stable at 12.0 VDC, the error should no longer trigger.