Skip the auto shop - Our mechanics make house calls

Q: New alternator works fine. Test is fine but battery light in dash is still on. How come?

asked by on

2004 toyota tundra replaced alternator because it failed. Did test after new install, everything is up to specs but battery light in dash is still on. Can you tell me what it means?

A: Hello there, the battery light on your 2004...

Hello there, the battery light on your 2004 Toyota Tundra is there to warn you that the alternator output is out of specifications. If the alternator output is to low or high, the light will be on. The alternator output will need to be tested with a load test to determine if other issues are present. A qualified technician, such as one from YourMechanic, will be able to diagnose the battery light and perform any repairs that are required.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
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

Get a quote

What others are asking

Q: Lights blinking after water got in a 1996 Mercedes Benz

The Battery Light typically just means that the alternator isn't charging the battery. If you get through any water in Mercedes, those cars are made up of many electronics, so I hope you have full coverage. If you don't have...

Q: 2003 MVP van won't start?

Hello...I will help you as best I can on this. First, to help you if future incidents arise, the most important thing to keep in mind when dealing with a car is it best to never replace anything, like a...

Q: Poor charging after replacing alternator - why? 2007 ChevySuburban

Hi - I suspect the wavering voltage you describe is either the serpentine belt too loose (tensioner), or the voltage regulator on the new alternator is defective. If the serpentine belt tensioner is loose, it can slip-grab-slip-grab as you describe....

Related articles

P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.