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sunshine03
Dec 29, 2007, 06:12 PM
Hi

I have a question that could deal with anything electrical.I was told that hot and cold temperatures can control how electricity flows through older circuits.Is it true that all of the plastic and metal parts of connectors,relays and other things-can expand when hot,contract when cold and actually work themselves apart (or hang up as with relays) breaking the circuit,and any old grease and gunk can make things worse (grease getting cold and hard-stuff like that)? Could this be the case in colder months when there is a slight delay between the time you flip the switch and when the lights accually come on-its like the current has to punch it's way through?
Thanks a lot for your time and years of experience

tkrussell
Dec 30, 2007, 08:08 AM
While temperature does affect the operation of any mechanical device, it does not affect "current".

Very low temp, close to Absolute Zero, affects the properties of conductive materials, hence, this is what makes Super Conductors work so well, by lowering the resistance of metal.

A light that comes on slow or flickers may be a fluorescent lamp, which needs a few moments for warmup.

If an incandescent lamps comes on slow, it more than likely is the switch, again a mechanical device, that has a weak spring, or, the grease inside is thick with dust, or otherwise, causing the mechanism to act slowly.

"Current" does not need to punch through. Give it a path and it will flow.

What exactly is your observation?

sunshine03
Jan 3, 2008, 03:37 PM
Hi Guys
I HOPE THIS ISINT TOO LONG

Thanks for the feedback.Sorry for not including the examples in my previous note.The first is my old Nissan car-when the weather is cold and I need the headlights,the headlights and dashlights take up to a min or more to illuminate after the switch is turned on.The second example is when its cold outside our home phone completely stops working.These problems always occur when the outside temperatures drop into the 40's and below.But when the temperatures warm up into the 50's and above-the problems disappear as if nothing was wrong.These things have been going on for so long-we have just about accepted them as normal.When I started asking around about this problem I found many people have experienced these things-but nobody can explain it.Its hard to recreate the conditions that cause the problems,so techs and repairmen can't find anything wrong when you call on them for help.The guys at Advance Auto said problems like these have baffled techs for years.These "GREMLINS" create poor performance,can burn up contacts,deteriorate components,and other bad things.They also said if a person understood what was going on-electrical maintenance and troubleshooting would be much easier on techs and the customers.Then one of the guys spoke up and said this would be a good PHYSICS QUESTION-so here I am.Aside from myself,I hope this discussion helps everyone who has had,or is having to deal with this situation.
THANKS EVERYONE!

tkrussell
Jan 3, 2008, 04:45 PM
Metal expands and contracts more than assumed, and plastic even more so, measurable even.

At any connection, most likely a ground, there is this movement of connections that can be enough to create a loose connection when cold.

If you live anywhere near the northeast, with temps close to zero tonight , bring it to the shop so the techs can work it cold in the morning. They will see if for themselves.

KISS
Jan 3, 2008, 06:36 PM
The car thing: Might be poor contacts on the headlight fuses, if you have them. Remove the fuses and re-install.

The telco thing: Go outside and when the line is dead, go outside and plug your phone into the test port and see if you have a dial tone. If you don't, call repair from a neighbors phone and ask them to do a line test NOW. If they don't do it now the problem will fix itself.

Make sure you can do the outside test when the lines are working. You need to open your side of the NID and remove a jumper. Then insert your phone in the jack. This connects to the telco side only and disconnects what's in your house.

Cobraguy
Jan 4, 2008, 07:51 AM
I haven't seen headlight fuses in years. So if you have them, your car is pretty old and you could have other degradaded circuit problems. But KISS has a good point. If it does have fuses, clean the contacts and re-install. My guess is it has a circuit breaker for the headlights. Same procedure applies. If it does indeed have fuses, replace them with the appropriate CB. At least they will recover automatically and you won't be in the dark somewhere trying to find a fuse. Most newer vehicles use relays for the headlights. These will have CB protection also. Plus, the control system for the relay will have a fuse. This fuse will more than likely also have other circuits on it. Confusing I know. But a thorough inspection of the entire headlight circuit should result in finding the problem. But Tk has what is most likely the problem. Well over 90% of all vehicle electronic problems are ground related. Locate, clean, and refasten all grounds. That's probably your problem. Now, older Nissan's have another peculiar problem. They use body panels as part of the vehicle grounding system. If these panels fatigue and corrode at the joints, you will lose your grounding circuit and all kinds of weird things will happen. Turn on the wipers and the turn signals come on for example. Seriously... VERY weird things. I would run across this with vehicles who have been in an accident and had panels replaced. The only solution at that point is to start installing ground wires throughout the car connecting panels to the subframe, etc. I've spent 12 hours running down these problems on Nissans before I found out just how they engineered their circuits. Thank God later technology required better engineered grounding systems.

KISS
Jan 4, 2008, 10:59 AM
Hey Cobraguy:

My 80's Celica and 2000 Solara have a fuse for each beam located in the engine compartment. Domestic US cars go the circuit breaker route. That why my headlamps started to blink back in the 70's when the filament of one bulb shorted.

Got to watch them grounds.

Cobraguy
Jan 5, 2008, 08:39 AM
By Geroge you're right KISS. Many imports do use the fuse route. I don't work on those a lot! LOL Domestics used to use fuses too, but that was many years ago. Nothing worse than blowing headlight fuses on a dark highway somewhere.

sunshine03
Jan 5, 2008, 12:03 PM
Hi
Its me again.And when the guys at Advance said contacts can burn up-they weren't talking
About an actual fire.They were talking about as the contacts are weakened and fouled
From age and the expanding and contracting from temperature - current trying to get
Through this type of connector will just burn it to the point it can't work any more ?
I hope I said this right.
Thanks Guys

KISS
Jan 5, 2008, 08:52 PM
4 fuses for the headlamps. Not so bad. At least they won't blink.