pics of my melted fuse box (finally)

[eethirtyfour]

So my heater stopped working, and I found this a while back but i'm finally posting pics. one time while it was in this condition someone turned on the heater and it worked, meaning theres a short somewhere in my car. also there is some fuse broken and melted that was covered by rubber. someone please help me identify it.










THaNKS

[Racerhoze]

Hey, samesies!

[darknezz7]

dear god, is there a way to prevent this or a reason it happens? is it only on the 525 and 535 or all e34's?

I DO NOT ever want to see something like that in my car, thats horible...

oh and that other fuse covered by rubber looks like an aftermarket fuse for like and amp or something, but I'm not sure.

[ljarseneau]

Wow, I hope your not putting in a 30 amp fuse when it calls for a 15?
What else could cause that?

[raceyBMW]

Wow on the exploded fuse!

The other with rubber top and red wires looks like its for an aftermarket alarm or radar.

[E34M60]

sheesh, I wanna prevent that from happening.

[sfgearhead]

slot 19 says rear fogs on that panel. did someone tap into that circuit for something else?

i have no idea what would cause that, the fuse should catch it. scary.

[zubbie]

Have seen this before. Not sure what causes it other than corrosion in the box. There is a thread somewhere with the process of replacing the entire box.. yikes. lots of wires

[ross1]

Bummer
The fuse holder in your hand isn't factory equipment. Someone has been fooling around in there already.
I have a fuse box you may have for beer and shipping. Plug the unburnt connectors from your old one into the "new" one and splice your wires to the others.
Get the original problem sorted or you'll be doing it again and not likely to find a cheapo fue box.

[Racerhoze]

Have seen this before. Not sure what causes it other than corrosion in the box. There is a thread somewhere with the process of replacing the entire box.. yikes. lots of wires

Yep. Mine was exploded, and the replacement box Binjammin sent me had signs of corrosion on the same fuse. So this is just a warning for everyone to check for corrosion on your fuses, otherwise you could be dealing with this mess. I replaced my entire box. PITA.

[eethirtyfour]

I remember reading that extended electricity going to a broken heater blower motor can cause this. I didn't even know I had a car alarm...

How much would putting a new fuse box in cost if I had my mechanic do it

[BBnGG E34]

...I replaced my entire box. PITA.

Yikes! I'll go check mine right now. I would not want to do that.

[Binjammin]

Yep. Mine was exploded, and the replacement box Binjammin sent me had signs of corrosion on the same fuse. So this is just a warning for everyone to check for corrosion on your fuses, otherwise you could be dealing with this mess. I replaced my entire box. PITA.

It did? Sorry man, I don't remember you ever saying anything.

[acepilot]

Looks like there's a few fuses we need to all check and run some sandpaper thru them. I know my recent rear defroster failed because of a cooked fuse. That's not even in the same area! Do they make a fuse with not only an amperage but a temperature sensor/rating as well? It looks like we need to replace or check all of ours.

Ace

[Racerhoze]

It did? Sorry man, I don't remember you ever saying anything.

No worries! The replacement diy said it would be a good idea to sand down all contact surfaces anyway for good connections. It was just a bit of green corrosion, but I thought it was interesting that it was the same fuse that had catastrophically failed on mine.

http://bmwe32.masscom.net/
There is the diy I used, just click fuse box rebuild.

[IT Jedi]

OMG that was hideous! Years ago I had a Saab Guru told me to cycle your fuses every year. Just taking them out and reseating them or new ones could (in his estimation) prevent surprise failures. Seems that doing this to sensors works too.

If there is corrosion weakening the connection beyond your fuse (or before it in the circuit), good luck

[CleanE34]

oh wow. i'm about to just go and buy brand new fuses for everything.

[scoops]

oh wow. i'm about to just go and buy brand new fuses for everything.

haha same here, now im just kinda scared.

[jphjones]

I had same fuse melt on me two, jumped to the neighbor and fried it too. I realized soon enough to file down connections and replace. Almost burnt a hole in the top of the box. Weird because the blower worked fine before/afterwards.

[SwissCheeseHead]

Wow. Thanks for the bump. I should go and replace a bunch of fuses as mine are all still the original ones. Ugh...just another thing to add onto the list.

[djb2]

Wow. Thanks for the bump. I should go and replace a bunch of fuses as mine are all still the original ones. Ugh...just another thing to add onto the list.

Inspect the originals, but don't replace them if they are in good condition.

Look at the picture above. One of the red 10A fuses adjacent to the burnt spot was replaced. It has a transparent plastic case. It's likely the failed one was a replacement as well.

Many replacement fuses have much thinner blades. The thinner blades don't result in the same contact pressure, especially after the thicker factory fuse has been in the connector. The thinner metal also has higher resistance, and doesn't transfer heat away from hot spots as well.

Further hints that the fuses are to blame is the burnt-out aftermarket fuse holder. That should never happen. The fuse element should safely blow well before the case melts. Once could be corrosion on the fuse holder. Twice points to defective fuses.

Bottom line: check your fuses if you like, but replacing them could cause the very problem you are trying to avoid.

- - - Updated - - -

Wow. Thanks for the bump. I should go and replace a bunch of fuses as mine are all still the original ones. Ugh...just another thing to add onto the list.

Inspect the originals, but don't replace them if they are in good condition.

Look at the picture above. One of the red 10A fuses adjacent to the burnt spot was replaced. It has a transparent plastic case. It's likely the failed one was a replacement as well.

Many replacement fuses have much thinner blades. The thinner blades don't result in the same contact pressure, especially after the thicker factory fuse has been in the connector. The thinner metal also has higher resistance, and doesn't transfer heat away from hot spots as well.

Further hints that the fuses are to blame is the burnt-out aftermarket fuse holder. That should never happen. The fuse element should safely blow well before the case melts. Once could be corrosion on the fuse holder. Twice points to defective fuses.

Bottom line: check your fuses if you like, but replacing them could cause the very problem you are trying to avoid.

[Binjammin]

Inspect the originals, but don't replace them if they are in good condition.

Look at the picture above. One of the red 10A fuses adjacent to the burnt spot was replaced. It has a transparent plastic case. It's likely the failed one was a replacement as well.

Many replacement fuses have much thinner blades. The thinner blades don't result in the same contact pressure, especially after the thicker factory fuse has been in the connector. The thinner metal also has higher resistance, and doesn't transfer heat away from hot spots as well.

Further hints that the fuses are to blame is the burnt-out aftermarket fuse holder. That should never happen. The fuse element should safely blow well before the case melts. Once could be corrosion on the fuse holder. Twice points to defective fuses.

Bottom line: check your fuses if you like, but replacing them could cause the very problem you are trying to avoid.

- - - Updated - - -



Inspect the originals, but don't replace them if they are in good condition.

Look at the picture above. One of the red 10A fuses adjacent to the burnt spot was replaced. It has a transparent plastic case. It's likely the failed one was a replacement as well.

Many replacement fuses have much thinner blades. The thinner blades don't result in the same contact pressure, especially after the thicker factory fuse has been in the connector. The thinner metal also has higher resistance, and doesn't transfer heat away from hot spots as well.

Further hints that the fuses are to blame is the burnt-out aftermarket fuse holder. That should never happen. The fuse element should safely blow well before the case melts. Once could be corrosion on the fuse holder. Twice points to defective fuses.

Bottom line: check your fuses if you like, but replacing them could cause the very problem you are trying to avoid.

That's unfortunately bad advice, as this is a well documented issue caused by the blower motor failing. It's the cause of most e34 fires, and if you find this type of damage the primary repair should be replacing the blower motor, THEN repairing the wiring. That's assuming the harness hasnt suffered from and cross connections from melting, which is extremely likely as well. Dont just repair the damage and assume everything is fine, very common that it isnt, and a fire will result. This is one of those "Cant stress this enough" type of scenarios, if you have this type of damage to your car, inspect your harness before your car burns down. Once it starts burning it's virtually impossible to extinguish before the car is totaled.

[demetk]

I had the similar problems with that fuse on the 91. Further investigation revealed that I had two time bombs on my hands, a corroded resistor pack as well as stiff blower causing higher than normal current draws on that fuse. The fact that the fuse holder also had corrosion just added to the problem.

[djb2]

There is no evidence that the blower had anything to do with the failure above.

The fuse was for the fog lights, not the blower circuit. The blower fuse was fine.

It's likely that someone put in higher wattage fog lights plus wired in additional aftermarket lights. They did use an inline fuse holder with the additional wiring, but had the same bad fuses in both.

A failing blower might cause a fire at the overheated motor. It should never cause a fire in the fuse box, if the correct fuse is installed. The problem comes when you substitute a higher current fuse, or use a substandard one with thin blades that don't make good contact. Or worse, something sold as a fuse that doesn't provide any circuit protection.

[demetk]

Sorry I thought that was the blower fuse. Carry on.