Electrical System Repairs
Wiring faults, ECM and ECU diagnostics, lighting, charging systems and sensor replacement on tractors and trailers.
Learn moreMobile roadside, six days a week
Battery Replacement and Testing
Replacing batteries without testing the charging system just buys you a few weeks. We test the whole circuit so the new batteries last as long as they should.
Battery Service in Baltimore, MD
Batteries are the most commonly replaced part on a heavy truck and one of the most commonly replaced unnecessarily. A truck that will not crank might have flat batteries, but the reason they are flat is what matters: a failing alternator, a corroded ground, a parasitic draw from an aftermarket accessory, or simply four batteries where one weak cell is dragging the whole bank down. Testing the bank and the charging circuit takes half an hour and regularly saves the cost of the second set.
Equipment and capability
Mobile units carry conductance testers, carbon pile load testers, current clamps and battery stock in the common group sizes, so a battery call is normally resolved on the first visit. Jump start capability is on every service truck, and we will always test before we simply boost you and leave.
Mobile roadside, six days a week
Covering Baltimore City and 29 surrounding communities, out to roughly 30 miles from the shop on Ponca Street.
See the areas we coverWhat battery service covers
The full scope of the work, so there is no ambiguity about what is and is not included when you approve a job.
- Individual battery load testing so a single failed unit is not hidden by the bank
- State of charge and state of health testing with a conductance tester
- Battery replacement in matched sets with the correct group size and cold cranking rating
- Battery box, tray, hold down and cable inspection and replacement
- Terminal and cable end cleaning, replacement and corrosion protection
- Alternator output and ripple testing under load
- Starter draw testing to catch a starter that is pulling the bank down
- Ground strap and chassis ground inspection, a frequent cause of hard starting
- Parasitic draw testing to find what is discharging the bank overnight
- Jump start service anywhere in the Baltimore metro area
- Battery disconnect switch and isolator testing
- Disposal and recycling of the old batteries
When you need this service
If you recognise any of these, it is worth a call before it becomes a roadside call.
Slow cranking, particularly on a cold morning
Clicking from the starter with no crank
Batteries need a jump more than once in a season
Dash voltage reads below 13 volts with the engine running
Visible corrosion, swelling or a cracked case on any battery
Lights dim noticeably when accessories are switched on
Charging system warning lamp illuminated
Truck starts fine after a run but not after sitting for a day
How we approach it
The sequence matters as much as the repair. Working through it in this order is what stops you paying for parts the fault never pointed at.
- 1
Test before replacing
Every battery in the bank is tested individually. One bad unit in a set of four will pull the others down and hide itself in a bank level test.
- 2
Check the charging side
Alternator output, ripple and belt condition, plus voltage drop on the charge cable. New batteries on a weak alternator is money spent twice.
- 3
Check the discharge side
Parasitic draw measured with the truck shut down, and starter current draw measured during cranking. Both are common causes of a bank that keeps dying.
- 4
Replace as a matched set
Batteries go in as a set with the same group size, rating and age. Mixing a new battery into an old bank shortens the life of the new one.
- 5
Clean, protect and verify
Terminals cleaned, hold downs secured, protectant applied, and a final charging voltage check at idle and at high idle.
Related services
Faults rarely sit in one system. These are the ones that most often come up alongside this work.
Emergency Roadside Assistance
Mobile assistance across the Baltimore metro area for tires, fuel, jump starts, air faults and breakdowns.
Learn morePreventive Maintenance
Scheduled PM services, oil and filter changes, fluid checks and DOT pre-trip inspections, on your yard or ours.
Learn moreFurther reading on battery service
Why Your Truck Batteries Keep Dying After You Just Replaced Them
New batteries that go flat within weeks are almost never defective batteries. Three tests find the real cause and they take about forty minutes.
Read the articleElectrical
Why Your Truck Batteries Keep Dying After You Just Replaced Them
New batteries that go flat within weeks are almost never defective batteries. Three tests find the real cause and they take about forty minutes.
3 min read
Book battery service
Send the unit details and the symptom and dispatch will come back to you. If the truck is off the road right now, call instead.
Faster by phone
A form is fine for scheduling. For a truck that is stopped, a call gets a unit moving while you are still describing the problem.
(443) 630-6669- Call out fee and labour rate quoted before we roll
- Work stops and you get a call if the job grows
- Itemised invoice with parts, labour and measurements
Battery Service questions
Drawn from the questions we get asked most about this specific service.
Three to five years is typical for a highway tractor. Trucks that idle heavily, run a lot of hotel load, or sit for long periods between runs tend to sit at the shorter end. If yours are failing inside two years, something else is wrong.
If the bank is young and one unit failed early, a single replacement can work. On a bank that has been in service two years or more we recommend replacing as a set, because a new battery paired with tired ones is dragged down to their level.
Yes, and we do that constantly. We will also test while we are there so you know whether you are going to be calling again tomorrow morning.
Usually a parasitic draw from an accessory, an inverter, a reefer control, or a module that is not going to sleep. Occasionally it is a corroded ground. We measure the draw and isolate the circuit rather than guessing.
Yes, they go for recycling and the core credit is applied to your invoice.
Yes. A fleet battery audit before winter is one of the cheapest breakdown prevention exercises available, and we can record state of health by unit number.