RV Battery & Charging System Repair

On-site testing, replacement, and lithium upgrades for RV house batteries. Local pros also check the converter, charger, and any slow drain to find why your rig won't hold power.

A dead or dying battery bank is the top reason an RV won't power up. And it is rarely as simple as old batteries. A local pro tests before selling you anything. Each battery gets a load test. The pro measures the converter and charger output and checks the shore-power, solar, and alternator charging paths. That shows if power is going in and staying in. Just as often the batteries are fine. The real cause is a tired converter, a corroded ground, or a slow drain quietly pulling the bank flat while the rig sits in storage.

When batteries are truly done, a local pro replaces them on-site. That means sulfated, swollen, or unable to hold a load. Local pros handle flooded and AGM deep-cycle types and full lithium (LiFePO4) upgrades with the right charge profile and, when needed, a DC-DC charger. Texas heat is hard on batteries. So the pro also checks the terminals, cables, and grounds that heat and vibration loosen. Large custom lithium and inverter builds or a rewired main harness are the exception. Those get scoped as bigger project work.

Sound familiar?

Batteries go dead overnight or won't hold a charge
The rig won't power up on battery, only on shore power
Batteries read low even after driving or a full charge
Lights dim or flicker and the pump runs weakly
You want to upgrade from lead-acid to lithium

How the diagnosis works

Load-test each battery against its rated capacity
Measure the converter and charger output and charge voltage
Check the shore-power, solar, and alternator charging paths
Test for a slow drain with the rig sitting still
Inspect the terminals, grounds, and battery cables for corrosion

How the repair typically goes

Replace failed batteries or do a lithium (LiFePO4) upgrade
Replace or repair a failed converter or charger and set its profile
Repair corroded grounds, terminals, and undersized cables
Find and fix slow drains pulling the bank down
Check charge and hold under load before closing up

Good fit for mobile repair

Battery load testing, replacement, and lithium upgrades
Converter, charger, and DC-DC charger repair or replacement
Slow-drain diagnosis and ground or cable repair

When a shop is the honest answer

Large custom lithium and inverter builds beyond on-site work
A damaged main wiring harness that needs a full rewire

Common components and causes

Deep-cycle flooded, AGM, and lithium (LiFePO4) batteries
Converter or charger and DC-DC chargers
Battery cables, terminals, and lugs
Battery isolators and lithium BMS
Grounds and battery-bay bus bars

Battery age and sulfation from sitting discharged
Texas heat shortening battery life
Slow drains draining the bank in storage
A failed or underpowered converter or charger
Corroded or loose terminals and grounds

Safety first

RV batteries hold dangerous energy. A dropped wrench across the terminals can arc, burn, or split a battery. Lead-acid gas and lithium faults are both real hazards. So a local pro makes connections in the right order with the right protection.

What affects the price

Every visit starts with diagnosis and a written quote before repair work begins. These factors move the number:

Battery type and count (lead-acid versus lithium)
The size of a lithium upgrade (charger, DC-DC, BMS)
Whether the converter or charger needs replacing
How long it takes to trace a slow drain

How much does mobile RV Battery & Charging Repair cost?

Most mobile RV Battery & Charging Repair runs $150 to $700 for most testing, charging, and replacement work. On-site labor typically runs $120–$175 per hour, with a service call of $95–$150, credited toward the repair. Simple fixes cost the least. The final price depends on parts, roof or slide access, and your rig make and model. These are rough ranges, not a quote. Every visit starts with an on-site check and a written quote before any work.

Battery & charging-system diagnostic: $95–$200
Deep-cycle battery replacement (per battery + install): $200–$450
Lithium (LiFePO4) upgrade: $600–$1,800+
Converter/charger replacement: $300–$650
Parasitic-draw diagnosis: $150–$350
On-site labor rate: $120–$175 per hour
Service call / diagnostic: $95–$150,credited toward the repair

Want a real number for your rig? Call (830) 402-5300 and tell us what it is doing. You get a written quote before any work begins.

Where this service is available

RV Electrical Repair
Careful 12V and 120V fault tracing, converter and inverter repair, battery system service, and shore-power troubleshooting at your site.
RV Solar Repair
Local pros test and fix RV solar systems, from panels and charge controllers to wiring and batteries. They also install right-sized upgrades at your site.

Frequently asked questions

Why do my RV batteries keep dying?

Both a bad battery and a bad charging system are common, so a local pro tests to find the real cause first. The pro load-tests each battery. The pro checks the converter and charger output. The shore power, solar, and alternator charging paths get checked too. The pro also looks for a hidden draw that drains the batteries while the RV is parked. If a battery is worn out or won't hold a load, the pro replaces it. That includes lithium (LiFePO4) upgrades. If the batteries are healthy, the fix is often a weak converter, a bad ground, or a hidden draw.

How is mobile RV repair priced?

You pay a service-call fee that covers travel and diagnosis. Then you pay for parts and labor on the repair you approve. A local pro gives you the diagnosis and a clear quote before any repair work starts. A pro never works on an open-ended okay. A few things change the price. Those are the part type, how hard the access is, and the size of the repair. Each service page explains this.

How quickly can a local pro get to me?

It depends on a few things. Your spot in the service area matters. So does how busy local pros are and whether your problem is an emergency. A local pro books scheduled visits for a time window and puts emergency calls first by safety. When you call, we take your request and share a real ETA from the pro instead of a blanket promise. We also follow up with you if the schedule changes.

Need rv battery & charging repair?

Call for honest phone triage, or send a service request and dispatch will follow up with a realistic window.

Call (830) 402-5300 Request Service