Skip the auto shop - Our mechanics make house calls

Q: Corrosion and battery acid on negative terminal connector.

asked by on

I paid a good chunk of money to fix several things wrong to get my check engine light off on my '06 VW Jetta about 2 months ago. Some time later it came back on. It turned off and came back on occasionally, but lately it's been staying illuminated. I've taken it to AutoZone twice now for a diagnostic on it and their readers never finds an error code. The worker told me to try resetting it by taking off the negative terminal from the battery for a bit and then reconnecting it. As i was fixing to do so, I notcied there was a lot of corrosion and what looked like battery acid on the connector so i didn't want to mess with it. Could this have anything to do with the check engine light or why his reader isn't able to pick anything up? Thank you in advance for a response.

A: Hi there. Poor electrical grounds can creat...

Hi there. Poor electrical grounds can create unusual electrical problems. The corrosion at the negative battery terminal is most likely, the result of a leaking battery and should be replaced. Not all code readers are German car friendly. I recommend having your vehicle’s check engine light is on be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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: Diagnostic code P0721

Hi....the best thing to do is request a diagnostic based on the trouble code, P0721, that you have in hand. Resolve that first as the fault behind the trouble code may account for the shift difficulty you are having. The...

Q: Cooling fans not working

If your cooling fan is inoperative, I would start by having a mechanic check the fan for power. If the fan is getting twelve volts but does not work, the fan is faulty. If the fan is not getting battery...

Q: Car only cranks but won't start

The battery is the most likely cause of any no start condition. Even if the battery is on the border it may not have enough power to start the car, but the accessories may turn on. Other causes are the...

Related articles

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...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.
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.