Nine systems, one order. A coach rarely fails all at once, and it is easier to learn when you take them in the order they can hurt you.
Every system below is a separate document in the manuals section, and each one has its own way of failing. Knowing what a system does when it is working is what lets you read a symptom later, and it is the one thing a fault guide cannot supply, because a fault guide starts from something that has already broken.
| System | What it does when it is working | When it breaks |
|---|---|---|
| Shore power and the 120-volt side | Brings 120 volts in from the pedestal and feeds the outlets, the air conditioner, the microwave and the water heater's electric element. | Outlets not working |
| The 12-volt house system | Runs the lights, the water pump, the furnace fan, the fridge's control board and the slide-outs, all off the house battery. | 12-volt faults |
| The battery and its charging | Keeps the house battery full from shore power through the converter, and charges it from the engine while you drive. | Converter not charging |
| Fresh water | City water through the inlet, or the tank and its pump, out to every tap, the toilet and the shower. | Water and plumbing documents |
| Waste | Holds what the sinks, the shower and the toilet send it, until you dump it into a sewer connection. | Tank and sanitation documents |
| The water heater | Heats water on propane or on 120 volts, into a tank that has to be full before either one is switched on. | Water heater not heating |
| Propane and the fridge | Cooks, and runs the absorption fridge on propane when there is no hookup, though the fridge's board still needs 12 volts to decide anything. | Fridge not cooling |
| Heat and cold | The furnace warms the coach in winter and the air conditioner cools it in summer. Both are the largest draws on the coach, and the furnace will not light at all without enough 12-volt power to spin its blower and close the sail switch. | Furnace not working |
| The extras | Solar, a generator and an inverter are three more ways to make or move power, none of which a first trip depends on. | Solar not charging |
The order below is not alphabetical and it is not the order a maker's manual lists them in. It runs from the system that can injure you, through the one that imitates all the others, to the ones you can safely leave until you have slept in the coach a few nights.
The 120-volt side is the only part of a coach that can kill you, and it is also the first thing you connect, so it gets learned first. What to know before your first hookup: the pedestal is somebody else's wiring, a breaker on the pedestal is what you switch rather than the plug, and a coach with a wiring fault can put voltage on its own skin. The outlets and GFCI guide covers the chain from the pedestal inward, including why a GFCI will not reset and what hot skin is.
Half the coach runs on 12 volts, and a battery that is low makes the pump weak, the furnace fan slow and the fridge's board unhappy, so a voltage problem gets misread as three different faults. Learning this system second means you stop chasing the wrong part before you start. The 12-volt guide has the layout and the voltage drop test; the battery care guide covers what keeps a bank healthy, and the converter guide covers what charges it.
Two systems that share a set of pipes and a set of habits. Water in is city water or the tank and its pump, and water out is two tanks and a valve. Learn them in that order because the fresh side is where you will first notice a leak, and because every fault on the waste side is a smell or a reading rather than a flood. The water and plumbing documents are the maker's own, and the winterising guide doubles as the map of where the water actually sits.
Propane is the one fuel you can learn by smell, and the furnace and the fridge are its two biggest consumers. Two things are worth knowing before the first cold night: how the furnace proves itself safe to light, and that an absorption fridge needs the coach close to level to work at all. The furnace guide carries the carbon monoxide hard stop, and the fridge guide explains why level matters.
Solar, a generator and an inverter are all ways of making or moving power, and none of them is needed to spend a first weekend at a hookup. When one of them stops working, solar and the generator both have their own guide, and both begin by checking two things before anything is tested.
Two systems share one battery and one ground, and almost every confusing electrical symptom comes from that arrangement. 120 volts arrives at the pedestal and goes to the outlets, the air conditioner and any heating element. The converter turns some of that into 12 volts to charge the battery. Everything else runs off the battery at 12 volts.
Several components touch both halves, and that is where a fault crosses from one to the other: the converter, which turns 120 into 12; an inverter, if one is fitted, which turns 12 back into 120; and every appliance with a 120-volt element and a 12-volt board, which is the fridge in its electric mode, a dual-fuel water heater, and the air conditioner's controls.
What to leave off on the first night: the air conditioner until you know the coach's amperage and what the pedestal can give, and the water heater's electric element until you know the tank is full.
The manual in the drawer covers the coach. It rarely covers the appliances inside it well, because those are other makers' equipment, and it often covers several model years at once. Every appliance maker publishes its own document, and that is the one with the wiring diagram, the fault codes and the part numbers: find the label inside or behind each appliance for its model number, then open it in the manuals section, which links each document at the maker rather than rehosting it. If you do not know who made something, the brand list covers 44 coach makers and how far back each one's archive reaches.
Each system above has its own document set in the manuals section, and the fault guides are organised the same way: one page per symptom, each one citing the documents it rests on, and each one starting with the checks that cost nothing. The guide index is the whole set in one place, including the weight and towing material and the winter set.