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Alternator failure from bump in parking lot?

My car was hit in a parking lot a few days ago. I was in the store so I didn’t see it happen. It looks like just cosmetic damage, some scratches on the front bumper. However, when I turned the car on, it was making a whirring/whining noise it didn’t make before. It seemed to still drive fine, but by two days later it was totally dead. I took it to the Honda dealer today to get checked out. They say the alternator is dead, but they don’t see how it could be related to the fender bender. They do say that the sound was from the alternator. My question is, is the dealer right? Or could getting bumped while the car is off jar something and cause the alternator to fail? I know it looks like very minimal damage, but it just seems like too much of a coincidence to me that the alternator went out immediately after the car getting hit.

This one of those questions that just does not have a real answer. Bump is cause, possibly yes or no. Coincidence is the most likely answer. Even if you have full coverage insurance after you pay your deductible for the body damage they would not cover the alternator.

Possible ,but how would you prove it? I heard the click of my alternator blowing when I drove over some RR tracks and barely made it home with the engine dying in front of my house. The car was a 27 year old Valaint and a rebuilt alternator was only $25.

When I was rear ended while stopped at a red light it was much more than a ‘bump’. The plastic bumper cover had fairly minor damage but the energy absorbing structure behind it had done it’s job and was destroyed. I hope the dealership inspected it. Since you did not witness the impact it could have been more than a ‘bump’. Did the dealership disassemble the alternator to determine the cause of the failure? Impact damage to accessories, electrical connections, and drivetrain components can be unpredictable. Whirring/whining noise could be bearings, bushings, or a loose drive belt caused by impact.

I suppose something like that could happen. I’d guess that isn’t a likely reason, but at least it is a possible reason for the alternator failure. If it happened to me I’d be curious enough I’d want to to take the old alternator apart to see exactly what happened. Semiconductor devices inside the alternator could definitely be damaged by a big enough bump, especially if they were hot. The problem with that theory is a damaged semiconductor device wouldn’t usually cause a noise. But if you don’t have the skills to take it apart yourself, probably best to just replace the alternator and be done w/it. A postmortem on the old alternator would be an expensive thing hire out, just for satisfying one’s curiosity. And if a bump finalized your old alternator, that bump might have done you a favor. Better to happen now than when you are driving on the freeway in rush hour or in a remote location. At least now you know you’ve got a new alternator working for you.

Sooooo… what year is this mystery Honda and how many miles does it have on it?
That matters when you’re discussing a part failure. :relaxed:

2008 with less than 60k miles. We’re getting a second opinion, but it seems likely that we’ll end up paying for it. At least the people who hit our car were honest, so their insurance is taking care of the body work.

The last alternator that failed on me was right after I hit a speed bump. A failing alternator is a fragile thing. It had been whining for a couple of days and I was hoping it would last until the weekend. No such luck in my case.

External damage like broken connections can be inspected quickly. The alternator has to be disassembled to see if anything is broken inside. I don’t know if this would void the core rebate for the old one when the rebuilt one Is installed. At 9 years old, it is easily possible that this is a coincidence. I think of any repairs on my 12 year old Accord as maintenance. You might think of it that way too.

Missileman’s thought is a possibility.
It’s possible, even likely, on an alternator this age that it simply chose that time to die. It was, after all nine years young. And it didn’t dies until a few days after the bump. My vote is that it simply died when it died, regardless of the bump. Parts do that.

For the record, there’s no judge in the world that would find the bump as being the cause of a nine year old alternator dying. It simply was time. Now it’s time to forget about it and get on with life.