# Alternator Repair and Replacement in Upland > Alternator repair in Upland after testing confirms the fault. Route 66 Auto Repair explains replace vs repair, fits the right unit and verifies charging. Source: https://route66autorepairshop.com/electrical-services/alternator-repair Updated: 2026-09-17 Business: Route 66 Auto Repair, 1775 W Foothill Blvd, Upland, CA 91786, (909) 608-7699 Hours: Monday to Friday 8 AM–5 PM, Saturday 8 AM–2 PM, Sunday closed **TLDR:** We fix the alternator only **after testing confirms it**, explain **new versus remanufactured** options, and **verify charging** under load before pickup. Route 66 Auto Repair in Upland repairs and replaces alternators once testing proves the alternator is the part that failed. The alternator keeps your battery charged and powers the car while the engine runs. When it quits, the battery drains until the car stalls. We confirm the fault, explain your part choices, install the unit to spec and verify charging before you leave. ## Should the alternator be repaired or replaced? Most modern alternators are replaced as a unit. Internal parts such as the regulator, rectifier and bearings are pressed or sealed in, and a replacement unit is usually the more dependable path. Your choices are typically a new unit or a remanufactured one, which is a used core rebuilt with new wear parts and tested. We explain the difference in plain terms and put each option on the estimate. Some faults sit outside the alternator. A seized pulley, a broken plug or a burned charge wire can be repaired on their own. That is why we test before we quote. ## Signs the alternator is failing - Battery light on while driving - Headlights and dash lights that flicker or dim - A whine or grinding from the front of the engine - A battery that keeps going flat - Stalling after the battery runs down ## Our alternator repair process 1. **Confirm:** A [charging system test](https://route66autorepairshop.com/electrical-services/charging-system-test) and alternator check prove the unit is at fault. 2. **Estimate:** The written estimate lists part options, the access work involved and whether a belt is due. 3. **Install:** The alternator goes in with connections cleaned and bolts torqued to spec. 4. **Check belt and battery:** The belt and tensioner are inspected, and the battery is tested and charged. 5. **Verify:** Output is measured under load and the car is road-tested. ## What's included in alternator replacement - Test results confirming the failed alternator - Replacement unit matched to the car's output rating - Clean charge and ground connections - Belt and tensioner inspection - Battery test and charge - Output check under full load and a road test ## Why we also look at the battery A deeply drained battery can hurt a new alternator by forcing it to run at full output for a long time. We charge and test the battery before release. If it failed, [battery replacement](https://route66autorepairshop.com/electrical-services/battery-replacement) goes on the estimate as its own line. If the belt is glazed, we quote [alternator belt replacement](https://route66autorepairshop.com/electrical-services/alternator-belt-replacement) too. ## Now or later? **Need now:** - Failed output test - Battery light on with dimming lights **Need later:** - A minor pulley noise with normal output, monitored at the next visit ## How pricing and timing work Cost depends on the part option and on access. Some alternators sit on top of the engine, and others need parts removed to reach. Phone quotes are ranges until we see the car. We text you if the look window slips, and AAA members save 10% on parts and labor, up to $75. Warranty terms depend on the part and are written on the invoice. ## Aftercare The battery light should stay off. A short belt chirp on the first cold start can be normal as a new belt seats. A steady squeal or any warning light is a reason to call. ## Frequently asked questions ### Can I drive with a bad alternator? Only briefly. The battery powers everything until it runs out, then the engine stalls. If the battery light is on, drive straight to the shop or arrange a tow. ### Can I bring my own alternator? Yes. We inspect it first. There is no warranty on a customer-supplied part, and labor is still charged at book time. ### Will you show me the old alternator? Yes, old parts can be shown. For remanufactured units, the old one usually goes back as a core. --- Call (909) 608-7699 or visit https://route66autorepairshop.com/contact for a written estimate.