Alternator testing and replacement in your driveway
When the alternator stops charging, your car runs on battery power until it dies. We test the charging system where you parked and repair it on site.
- We come to your home or work
- You approve the price first
- Most jobs finish in one visit
Signs the alternator is not keeping up
Tools and parts come with the tech. Most jobs finish in one visit.
What the alternator does
The battery starts the car. After that, the alternator takes over. A belt from the engine spins it, and it makes the power for your lights, fans and computers while it recharges the battery. When it fails, everything runs off the battery alone, and the battery cannot keep that up for long.
Charging trouble can come from worn bearings or other parts inside the alternator, a bad voltage regulator, a loose or worn drive belt, or loose or corroded wiring at the alternator or battery. Engine heat and road dirt add wear over time.
If the battery light comes on while you drive
Take it as a sign to end the trip. Turn off what you do not need, such as the A/C, rear defroster, seat heaters and radio. One owner's manual says not to switch the engine off on the way, so you do not drain the battery further. Drive carefully to a safe place and stop there.
Once you are parked with the engine off, look at the drive belt that turns the alternator. If it is loose or broken, tell us when you book. Look without touching, since the cooling fan can keep running after the engine stops, and never reach near the belt or fan while the engine runs.
Battery or alternator? How we tell in your driveway
A dead battery and a failed alternator can end the same way, so we test before we replace. We check the battery's health first, then start the engine and measure the alternator's output at idle and with lights and fans on. We also inspect the belt, the tensioner and the wiring between the alternator and the battery.
If the alternator is the cause, you get the price first, and the swap begins only after you approve it. The tech carries the parts, and most jobs are done in a single visit. We credit our standard diagnostic fee toward the repair when you say yes.
Our area includes Allen, Plano, Frisco and McKinney, the remaining Collin County towns we serve, and Van Alstyne to the north. Fill out the form, open the chat, or reach (214) 784-2056 by call or text, and we confirm your time with a call or text.
Three steps. Usually one visit.
Most jobs finish in one visit.
Book online or call
Tell us the symptoms, your vehicle and your address.
We come to you
Your driveway, your office lot or the curb. No tow, no waiting room.
We diagnose and repair on site
You approve the price before any repair work begins.
Good to know.
Can I drive with a bad alternator?
Only a short way. The car runs on stored battery power, and when that runs out, the engine and lights can shut down. Head to a safe place, stop, and book a test.
Will a jump-start fix a bad alternator?
No. A jump can get the engine running, but if the alternator is not charging, the battery drains again. A car that dies again after a jump needs a charging system test.
Can a bad alternator ruin my battery?
It can. Running a battery all the way down again and again shortens its life. When we replace an alternator, we also test the battery and tell you if it needs attention.
What does a whining noise from the engine mean?
A whine that rises with engine speed can come from worn bearings in the alternator, or from a pulley or belt tensioner. We listen and test to pin down which one it is.
Rattling, grinding
or not starting?
Tell us what is going on. A mechanic comes to your driveway with the tools and the parts.
Open 7 days