Electronically controlled RV refrigerators came along around 1980 and are refrigerators that use a circuit board as an integral part of the heat source controls (a heat source is what heats the cooling unit: 120 volt heat, 12 volt heat, or gas heat). The trick to troubleshooting one of these refrigerators is to first know what it's supposed to do, when, and in what sequence. Then, after narrowing the problem down to a few components, the suspect components are tested. You won't be tracing electricity through the circuit board, but instead will be testing for what should be coming into the board and then back out.

To complicate matters, different manufacturers took different approaches as to how to incorporate a circuit board into their refrigerators. For troubleshooting purposes, we'll group the various refrigerators into types, discuss how they operate, and reference the components as we go along.

Dometic AES (first generation)
RM663, RM763, RM1303, RM2602, RM2603, RM2802, RM2803, RM3500, RM3501, RM3600, RM3601, RM3604, RM3800, RM3801, RM3804, RM4801, RM4804, RM7030 (below)

Dometic Second Generation Electronics S1521, S1531, S1621, S1631, S1821, S1831, RM2607, RM2611, RM2612, RM2620, RM2652, RM2807, RM2811, RM2812, RM2820, RM2852, RM3607, RM3662, RM3663, RM3807, RM3862, RM3863, RM4872, RM4873, RM7030 (below), RM7130, RM7732, RM7832, and NDR1062

Norcold 838 and 8310

Norcold Second Generation Electronics 652, 653, 662, 663, 682, 683, 6052, 6053, 6062, 6063, 6082, 6083, 6162, 6163, 6182, 6183, 8652, 8653, 8662, 8663, 8762, 8763, 8782, 8783

RM7030
The first RM7030 refrigerators came out with the first generation electronics and later models came out with the second generation electronics. The best way to tell the difference is by looking at the circuit board at the rear of the refrigerator and visially matching it up with the pictures on the two different generation pages.