Q: altinater is fine but battery light keeps coming on what could be the problem? came on 7 times while on the road

asked by on January 18, 2017

battery light continue to come on after altnator checked out ok same thing still occurs

My car has 234465 miles.
My car has an automatic transmission.

Battery Replacement $247.05 - $377.49 Get a Quote
Battery Light is on Inspection $94.99 - $114.99 Get a Quote

The battery should be load tested by a professional. Load testing can only be reliably performed on a fully charged battery. If the battery passes a load test be sure it is NOT a marginal pass in which case you should install a new battery to reduce diagnostic headaches as you seek a resolution to this. Batteries are a VERY important component in a car’s electrical system and the battery must be fully functioning to avoid electrical glitches. If the battery tests OK, you could have an intermittent fault in the charging circuit and that includes wiring, components, fuses, terminals, grounds, and so forth. Intermittent faults can be found using a data logger or, in your case, simply testing alternator output right at the moment the battery light comes on. An inadequately tensioned serpentine belt can also cause the issue you are reporting. If you desire that this problem be diagnosed by a certified Mechanic, dispatched by YourMechanic right to your location, please request a battery light diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing


Experienced Mechanic?

Earn up to $70/hr

What others are asking

Radio’s touchscreen died, what’s the problem?
Your touch screen system has a recall, R40 dated 7/28/2015, that pertains to the radio system being susceptible to a security vulnerability. The vulnerability could allow someone to access the system which could cause problems. The dealer will reprogram your...
How do I use the remote keyless entry (RKE) system to pop the trunk?
The remote keyless entry (RKE) transmitter allows you to open your trunk very easily. To do so, simply press the button on the RKE transmitter that looks like a car with its trunk popped. Hold the button briefly, and the...
Car making noise
Hello. There are many reasons for a car to make noise. There could be loose plastic, metal, and multiple moving parts. Being able to demonstrate the noise will aid in a proper diagnosis. I would recommend the aid of a...
Heater blows cold air
The AC system needs to have a performance check run. The AC compressor needs to be checked for operation and a set of AC gauges put on the system to help diagnose the issue. If the system is low dye,...
Car started vibrating a lot
Hello there. The LX470 does, in fact, take premium gasoline (https://www.yourmechanic.com/article/how-to-know-what-type-of-gas-to-use-by-jason-unrau). When a lower octane is used such as 87 unleaded than there is a possibility for the engine to knock. In most cases, the vehicle's computer will adjust to...
Everytime I drive my car is "putting" like it's going to lose power what is switching gear perfectly
Hello. There are a lot of things that can cause this. Most of the time it is caused by a worn out timing belt (https://www.yourmechanic.com/services/timing-belt-replacement) or a clogged catalytic converter (https://www.yourmechanic.com/services/catalytic-converter-replacement). It can also be caused by a failure int...
Smoke coming out of car and oil level is low
Hello. These are symptoms that you definitely don't want to hear. You are correct, don't start the engine, or drive the vehicle until you are able to get this fixed. Determine where the oil was pouring out (oil drain plug...
Code P0128
Hi There, As you know, code P0128 relates to the operation of the thermostat in your cooling system, specifically indicating that the thermostat (https://www.yourmechanic.com/services/thermostat-replacement) is likely stuck open, which results in the engine operating temperature never reaching the normal operating...
Where is the AC Compressor Control Relay on a 2001 Chevy Malibu located?
The A/C control relay is in the "Fuse Relay Center" which looks like a black plastic box in the under hood area. The relay may be a micro relay and will be labeled "AC Clutch". If you have a non...

Related articles

Can a Car Battery Freeze?
Cold temperatures can make it hard to start your car, and extreme cold can freeze a battery. Use a battery heater to make your car reliable in winter.
What Is a Vehicle's Electrical Control Unit?
You’ll You’ll hear the term ECU bandied about in automotive circles, but what does it mean? The most basic definition is “electrical control unit” (ECU) which is a generic term applied to any system that controls a system or subsystem...
How Long Does an Alternator Last?
Your alternator is a vital component in your car. It recharges your battery, using engine power, and it also delivers power to your...