Inspiron 8000 fan and thermistor sensor troubles

[DBLurker]

Hey All, I posted this over on the Dell forum, but havent had any replies yet so I though I would try here as well. Just in the last few days My Dell Inspiron 8000 has begun shutting down on me. I’ve noticed it was running very hot around 95 degrees Celsius, so i have a feeling its over heating. I ran Dells diagnostic program and it came up with 3 errors

Sodimm Thermistor sensor
Range test Fail
Result code 3900-0626
Temperature sensor out of range
temp 8C
Min 10C
Max 100C

Fan # 1 fail
Result code = 3700-011B
Expected fan on high RPM 10,000 Detected fan at RPM 1928

Fan # 2 fail
Result code = 3700-011B
Expected fan on high RPM 10,000 Detected fan at RPM 3754

Its a 900 MHz machine and I’m running Windows ME with the A22 Bios. So far I haven been able to find any clear resolution to the problem. Its past its warranty so Dells tech service is no help at all. So any ideas on what I need to do to fix this problem? I am hoping that just the fans have gone bad on me, they have been running poorly and very loud lately, but its worse now then ever as you can see from their RPM test results. I am thinking they will need to be replaced but does any one know what this Sodimm Thermistor sensor is? Is that part of the dual fan assembly? Or is it a separate component that will also need replacing. Then manuals make no reference to it so any help would be really appreciate. Thanks

DB

[confus-ed]

.. any ideas on what I need to do to fix this problem? I am hoping that just the fans have gone bad on me, they have been running poorly and very loud lately, but its worse now then ever as you can see from their RPM test results. I am thinking they will need to be replaced..

So am I ! .. thinking that the fan wants replacing, or maybe just cleaning ? Welcome to wd forums that 'lurker' (though if you are that then you were here already, & I don't need to welcome you, but that makes me confus-ed, so its a good job I already am !! )

Time for visual inspection methinks since the warranty period is over, open the case, find the cpu fan & is it all covered in 'gunk' ? Very probably ..

On the bit "what this Sodimm Thermistor sensor is?", well that can be a little circuit (for want of a better phrase), either on a probe which gets inserted under the heatsink when fitting the cpu, or on the motherboard itself - I personally don't think there's anything wrong with that, from what you are describing.

Fixing this is probably gonna mean a new fan & you can either replace this on its own (if you can source a fan of the right size), or buy a new heatsink & fan, but then you'll need to clean up the cpu & refit, which is harder than just swapping the fan (as generally its only held on by four screws) or if you are a real cheapskate (like me ! lol) you might maybe remove the fan & carefully clean it {& get all the dust etc out from the fins in the heatsink} & see how it goes (if its still noisey after cleaning, replace it )..

Let us know how you get on.

[NooNoo]

One tip, do not use any oil or wd40 like substances and then put the fan back... it will throw out the oil as it spins and nicely fry your motherboard.

[3fingersalute]

Was this laptop used in a dirty environment????

[DBLurker]

Thanks for the help Confus-ed. I’ve been lurking here for a while now but I appreciate the welcome. This forum has been a great source of information and has helped me out solving a few problems in the past.

So far I’ve cleaned the fans a bit with compressed air. The laptop has been used mostly in clean environments, and didn’t look too dirty. Unfortunately there was no improvement. I’ll have to open it up and try a more meticulous cleaning. I’ve been having trouble with the fans for a while now so I would not be surprised if its last leg. I’m checking into some replacement parts, and I just found that Dell has updated the bios for this model that’s supposedly optimized the thermal control algorithm, so I’ll be working on this throughout the week or so.

Also Thanks for the tip NooNoo, I had wondered if lubricant in the fan motors would help. I decided against it, glad my digression paid off.

Thanks again and I’ll let you know how it goes.

[Platypus]

Once fans become noisy & start to spin badly, they should simply be replaced. As NooNoo said, there's no value in trying to spray in something like WD40, it cannot get into the bearing and just gets flicked out again.

As an emergency measure, most fans have a label on one side which can be peeled back to reveal the bearing, usually down a recess under a little rubber or plastic bung. A drop of non-runny oil, like 10/40 engine oil, can be applied and the bung & label replaced to contain the oil. The fan should still be replaced as soon as practical.

[confus-ed]

Once fans become noisy & start to spin badly, they should simply be replaced..

Yeah I suppose .. but if its obviously just clogged up with gunk & that's the cause, not the bearing wearing then you spent some money you didn't need to really, do you chuck out your carpets when they get mucky ? Nope you vacuum 'em .. Some places 'fan cleaning' is routine preventative maintenance .

& a btw on your btw & your 'oil tip' - what happens if this is a synthetic bearing ? (will that not just leak out too ? as the bearing was never meant to have any lubricant in it ?)

[Platypus]

do you chuck out your carpets when they get mucky ?

what happens if this is a synthetic bearing ? (will that not just leak out too ? as the bearing was never meant to have any lubricant in it ?)

Depends on just how mucky they are I guess...

But I could have been more precise and said "noisy bearings", which is what I was intending, hence my agreement with NooNoo that WD40 will not cure it, and oiling instructions. Fans with noisy bearings should be replaced, not just for dirty blades.

Even for bearings which don't normally use oil, a viscous oil can be retained by capillary action for some time, and smooth the running temporarily if you don't have a replacement immediately to hand. The annoyance of rattling/squawking noises is reduced and RPM can be restored by damping the "thrashing" that a worn sleeve bearing can suffer.