Skip the auto shop - Our mechanics make house calls

Q: Lights

asked by on

When I start my car sometime the lights on radio&dash are dim when this comes on my running lights go right out when I shut off. Now sometime the lights are o k and then when i stop the lights go out in 30 sec.Back about 1 month my light came on but there was no codes I just reset it . Does not seem to be hurting anything. So what do think Thank you Jim

My car has 69000 miles.
My car has an automatic transmission.

Fluctuations in lighting output can be due to a bad alternator, loose alternator drive belt, wiring faults in the lighting circuit including bad grounds and a weak battery. I recommend you have the battery load tested and, at the same time, have the charging system output tested. Normally, at the battery posts, you should see a voltage of about 14.5 volts when the car is running but the exact specification will depend on your Factory Service Manual. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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: Can a Car Battery Freeze?

A new or nearly new car battery in most of today’s vehicles is fully charged if the voltage is at about 12.6 volts. When a battery starts to age the voltage that it can store will start to be less...

Q: Motor Locked up

Check to see if the starter motor pinion gear is jammed in the ring gear on the flex plate. On the off chance that somehow the transmission is the issue, you can also try disconnecting the torque converter from the...

Q: Reset service light

Hi. You will need to connect your vehicle to a scanner that has the ability to clear fault codes. The cheaper scanners usually do not have the ability to clear the codes, only retrieve them. If you don't have access...

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...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
What are the Car Pool Rules in Hawaii?
Hawaii is widely regarded as a land of vacation and relaxation, and as such, its scenic roads and routes are far better known than the state’s freeways. But, as with all...