Just Purchased - What is this.

PainterPaul · Post by **PainterPaul** » 16 Apr 2020, 17:54

Just purchased a 2004 S60 R.
Battery keeps draining.
Once you jump it, it runs fine.
Except for the drivers seat forward and back control won't work.
Don't know why.

I did notice that the fuse box cable is smoking.
Did the previous owner connect this wrong?

Is that why the cable is smoking?
What's wrong with this picture?

Thank you

Post by **June** » 16 Apr 2020, 17:56

No you need a new starter cable and fuse box.

PainterPaul · Post by **PainterPaul** » 16 Apr 2020, 18:06

Please explain why?

I really do want to learn.

Post by **June** » 16 Apr 2020, 18:22

That bolt connects to a section of contacts in the fuse panel. Volvo sells the metal piece of the fuse panel as of a couple years ago. You can play with it if you like, but in the end you will replace it. For the wire and fuse panel installed by Volvo in my 2004 S80 was like $500 and problem solved. They only replaced part of the fuse panel. As far as cleaning the contacts, tightening things up doesn't work. Apparently this issue was not uncommon on the 2004. I'll attach a photo of what mine looked like within a week of being cleaned and tightened up. It completely burned up while I was starting the car. My car to this day has its original starter. It's that connection point that causes the resistance down below. I don't exactly understand why. I just know the dealer replaced the starter cable and the inside of the fuse panel and problem was solved. One week prior to this photo it looked like your photo. June

PainterPaul · Post by **PainterPaul** » 16 Apr 2020, 19:01

Do you think that might be causing the
battery drain and
the driver seat forward and back control from not working too?
All the other controls seat controls work.

Post by **June** » 16 Apr 2020, 19:05

Here is the ticket where the cable and panel were replaced. Mechanic states resistance at lower fuse box. I was told at the time by the mechanic this was not uncommon, he had replaced many over the years on this model. June

Post by **SuperHerman** » 16 Apr 2020, 19:37

Battery cable looks like it is getting hot - means it is drawing too much current. Normally a fuse will blow.

You may need a new battery - have it checked or charge it and then check it. This may be an issue, but a battery cable should not smoke.

For seats you may have a blown fuse, or it may not be blown, but draining your battery.

Check your fuses. It is not unheard of for the wires on the seat to get pinched due to movement or for the wires on the control piece to pinch.

Right now you have a serious short some where in the system or a bad battery cable as June suggests. Either will cause excessive current draw from the battery.

Post by **amblerman** » 16 Apr 2020, 20:48

As others have mentioned, things are getting too hot.

As to why this is happening in the first place, I grabbed this from the web ".....but the cause of electricity being converted to heat is that the current is forced to flow through a resistance."

Under normal circumstances , the circuit is designed to properly handle the amount of electrical current flowing through it. Therefore the amount of heat generated will be safe, negligible and may not be observable without testing equipment .

So why are your wires and various connections not working properly anymore and getting too hot?

This could be due to several factors including corrosion of the wires under the insulation, corrosion at any of the connection points, corrosion of the contact points June talks about, poor connections at any point, manufacturing defect, breakage or de-lamination of the wires/contact points etc.

All of these could increase the overall resistance in the circuit and if the system is trying to draw the same amperage as it did when new, you will see an increase in heat. And in your case, more heat than the designers of that circuit expected. This is why things are melting.

Take a look at this post (not same car as yours) to see what I mean by corrosion of the wires. That *could* be happening under your insulation (or any conductive connection point in your circuit).
viewtopic.php?f=1&t=35208&start=30#p515279

In the above referenced post, the wire in question if made of 4 thin wires but the same principle could apply to the wire in your car.

The only real fix at this point is as June say. Replacement of wires and whatever might be an issue at the fuse box.
If this was caught early you might (I stress might....) have been able to address what ever was causing the increase in resistance from the get go. That could have eliminated or delayed the damage. At this point thought it's not safe and I'd be looking to do what June recommends.

NOTE: I am not an electrician so some of the description above me not be exactly technically correct. However one thing is absolutely true, for a given amount of current flowing through a circuit an increase in resistance will cause an increase in temperature.

-A

Post by **darrylrobert** » 17 Apr 2020, 07:07

How does that happen? Was the nut loose?..looks like only the starter cable is damaged.

Post by **jimmy57** » 17 Apr 2020, 08:03

The start of the fix is to get current draw for the starter checked. The starter draw on R models is 145 to 150 on any I check. There will be an initial jump to higher amperage as starter makes the first motion of crankshaft so the value listed is the continual draw once crank is moving. A problem with starter that causes high current drain is going to cause this again if not dealt with. Corrosion between those cables introduces resistance and thus heat. BUT, lots of cranking with a weak battery can also melt cables. When voltage is lower the current of a motor will be higher. Slow turning DC brush motors will use more current and your starter may be fine with a full charged good battery. Both sides of the lower cable, the bottom of the upper cable, and the top of the connection strip for the fuse box that is revealed when the two cables are removed. The connection strip below can get melted plastic on it and continue a problem but your photo looks like the problem is starter current. The stud and nut and the battery cable (the lower cable comes from battery in rear to this connection) do not look like the ones I've seen with loose nut and post corrosion that burns all three conductors. June's photo looks like the loose nut, burnt cables, plastic melted below condition. The starter cable may be useable if the end is soldered. The voltage drop of that cable will need to be checked once starter issue, if any, is resolved. voltage drop of that short cable should be 15 millivolts (.015V) or less. May be over that without soldering but should be less if soldered. Since you have been having serial weak battery problems your problem may not be like others who have had problems here and will not necessarily mean that cable has to be replaced. The seat and battery drain problem will need more investigation. Your issues may be with a bad power set module. Battery drain can be measured and the connections at power seat module disconnected to see if that makes the current consumption go down. Youtube is a good place to see current draw testing performed. Take note of the closing of each door latch and trunk latch with those left open for access. The latches must be closedso the systems in car believe those to be closed.