Battery fried and dome light caused wiring to over heat

welcome! no. do you know what wiring they are talking about? how much do they want? imo, this was all caused by them draining the battery on the showroom floor. they should have replaced it then, instead of charging it. i would force the issue up the food chain, all the way to toyota if necessary. all the best!

 

No, it's not normal. 5W light should not melt the wiring in any possible case. This should be a manufacturing defect. I would take the car to another dealer or contact Regional Toyota rep.

Alex

 

the $4,000. hybrid battery?????

 

interestingly, toyota puts the dome light fuse in with the boot up, so the car won't start if it's blown. no way leaving the dome light on can harm anything though, otherwise, there'd be thousands of burned up pri.

 

ask them to show you in the owners manual where leaving the dome light on will cause damage not covered by warranty.

 

if your hybrid battery was fried, it has nothing to do with the dome light. there is way more to this story than meets the eye. you need a serious conversation with toyota regional, and probably a new dealer. they sound mighty incompetent.

 

As an electrical engineer, I would absolutely declare that leaving the dome light on should not cause the wiring to overheat. That would indicate TWO electrical design defects: (1) specifying or installing wire that cannot safely carry the intended current, and (2) not specifying or using a fuse that protects the wire from overheat.

It is absolutely foreseeable and inevitable that numerous customers will leave the dome light on for indefinite periods. The historical precedence is that the car maker is not responsible for the battery's subsequent failure from this abuse, but they are still responsible to conform to electrical and fire safety standards that demand no wire or fixture overheating.

If dead batteries from left-on interior lights are a common problem in your household, I would suggest changing the suspect lights to low-current LED types. These won't prevent the problem, but will give 5X to 10X more time to discover and fix the problem before the battery goes dead. This really means that the LEDs can stay on all night without draining the battery, though they may not go all weekend.

But select LEDs for low current, not super high brightness. The brightest lamps available, much brighter than the OEM incandesent lamps, won't provide much time extension.

 

It is not likely that the dome light being left on that caused the wiring to be damaged.

It is more likely that it happened when the car was jumped, before it was delivered.

The wiring was more likely than not compromised at that time but did a slow degradation which might have been triggered by having the dome light left on. It is likened to the "straw that broke the camel's back."

The problem is trying to prove it.

 

As an EE, I'd ask what wiring was damaged. If it was a dome light wire, I'd point to the defect arguments above.

If it was just about any other wire, especially anything related the engine or propulsion, my manure detector alarm would be clanging. They would have to prove to me that the dome light was relevant. And do it in such a way that I couldn't show them a defect that was bound to fail soon anyway, even without the dome light, but under warranty.

 

Having done many defect and catastrophic investigations in aircraft systems failures, I don't believe that most dealers service departments are capable to find the true cause of the failure. The failure of the HV battery could have over heated the insulation and cause it to be burnt.

 

8 months old and 3,200 miles...even if the damage happened as they said (which it did not)...YOU ARE BEING PLAYED. I guaranty you a mechanic/electrician didn't say this damaged was caused by leaving the light on (unless aware of a manufacturing defect yet addressed by Toyota). Stop talking to the Service Adviser and go straight to the Service Manage/Director when you arrive, and as recommended accelerate this to next level corporate before you leave the Dealership. Make a log of everything to this point and beyond, have them document everything they said and did in the computer (and get all copies on the spot, not just receipts), ask for and keep the damaged wiring and items you are being asked to pay for, take pictures, take names and start talking about legal action. I am a very strong advocate of the "be firm, but above all be polite" school...but sometimes it's necessary to "also" be loud.

 

It should not, will not.......and if it does, it is either an engineering or manufacturing defect and should be covered under warranty.

You should NOT pay this bill........any part of it.

 

They should have given you a fresh battery at that point. Our 2010 came with a dead battery, and they tried every trick in the book to dodge responsibility. Had the car running when we showed up for a test drive.

He might have hooked up jumper cables, done it wrong, toasted everything.

I'd put my money on the tow truck operator. Try to get the wire harness covered, by all means, and I suspect they will if you persist.

But thank your lucky stars they replaced the hybrid battery. They could get sticky, say it's due to someone you hired messing with it.

 

Wire insulation is rated for a certain temperature. Most insulation becomes soft at around 200 degrees F.

A high amperage flow of current has to have melted the insulation.

I'd find out specifically which wire or wires were damaged. A photograph would help. If the insulation was melted, it would be pretty obvious.

 

I've left the rear hatch up and the dome light on overnight with no damage.