Staff Answer
Sep 25, 2026 - 08:40 AM
Zero amps on the DC heater leads means the heater isn't getting power in DC mode. Before blaming the DC board, check a few things:
1. Confirm a solid 12V DC is reaching the board in DC mode. Many 3-way fridges only run on DC while the engine is running or the charge line is live. 2. With the power off, check the DC heater for continuity. An open heater also reads 0 amps. 3. Check the fuse and the connections on the DC side.
If you have 12V in and the heater is good but there's no output, the DC Board 637764/628669 is likely bad. It has been discontinued by Norcold, so it's only available while our remaining stock lasts. If your fridge is also discontinued, our Norcold replacement guide shows the current replacement.
Since I can't confirm this 100% from here, please email us at info@rvfridgeguys.com or call 800-712-8822 with your model and serial number and we'll double-check it for you. You can also browse www.rvfridgeguys.com.
