# 12-Volt Electrical Systems Repair in Chino > OCRV Center traces and repairs the 12-volt DC side of your coach in our Yorba Linda shop, from parasitic drains and bad grounds to corroded connectors and dead circuits. Diagnostics start at $285 and are credited toward an authorized repair. The 12-volt DC system runs almost everything you touch when you are off shore power: lights, water pump, slide motors, control boards, and the propane and CO detectors. When a DC fault appears the symptom and the cause are usually far apart, so we test at the circuit and component level instead of guessing. All 12-volt work is done in shop at our Yorba Linda facility. ## 12-volt DC work we handle The DC side of an RV is a web of fused circuits fed from the house battery and the chassis system, tied together through busbars, grounds, and a fuse and distribution panel. Most failures we see are not the appliance itself but the path that feeds it: a loose ground, a corroded crimp, an undersized wire that has been overloaded, or a connector that has worked loose from road vibration. We load test each suspect circuit with a meter and a draw tester to find where voltage is dropping. - Parasitic draw and phantom battery drain diagnosis - Ground fault and voltage-drop testing across DC circuits - Corroded terminal, busbar, and crimp connector repair - 12V lighting, water pump, and slide motor circuit faults - Fuse and distribution panel circuit repair ## How we trace a DC fault in shop We start with a real diagnostic rather than swapping parts. With the coach on the bench we measure resting voltage, isolate circuits one at a time to find a parasitic draw, and check voltage drop end to end so a corroded ground does not get mistaken for a dead component. The diagnostic fee is credited back against an authorized repair, so the testing is the start of the fix, not wasted money. Once the fault is located we repair the actual cause: re-terminate the connection with the correct gauge and crimp, clean and protect the ground, or replace the failed run. A written estimate follows the diagnosis so you know the scope before any work begins. ## Frequently asked questions ### My RV battery keeps going dead even when everything is off, can you find why? Yes. That is almost always a parasitic draw, a circuit pulling current when it should be off. We isolate the DC circuits one at a time with a draw tester to find the culprit, then repair the wiring or component causing it. The diagnostic is credited toward an authorized repair. ### What is the difference between a 12-volt and a 120-volt problem in my RV? The 12-volt DC side runs off your house battery and powers lights, the water pump, slides, and control boards. The 120-volt AC side runs off shore power or the generator and powers outlets, the air conditioner, and the microwave. If something works on battery but not on shore power, or the reverse, that tells us which system to test. ### Is the electrical work done in-shop or do you come to me? In-shop only. Bring your rig to our facility at 23281 La Palma Ave in Yorba Linda and we handle the full diagnosis and repair there. We do not offer mobile or roadside service. --- Source: https://oc-rv.com/services/12-volt-electrical-repair/ OCRV Center, 23281 La Palma Ave, Yorba Linda, CA 92887. Phone (949) 799-3387. In shop only; insurance billed direct.