Question about Dell jt782 - Fan Assy Cpu Cooling, Optiplex 745, Usff

Open Question

Dell optiplex 745 rear fan failure

My employer has multiple 745s and the only thing wrong with them is "rear fan failure". Some rear fans work intermittently, but all need to be repaired. I believe the problem is with the fan's interface to the motherboard malfunctioning. I read about a fix where you could remove the interface from its socket on the motherboard and bridge the wiring to the interface supplying power and diagnostic info to the front fan, however I cannot find this post again to save my life. Does anyone know which function is associated with which color wire as I believe this is a proprietary wiring scheme? Or even better, does anyone know anything about the previous post I just referred to?

Posted by Anonymous on

6 Suggested Answers

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017

  • 24 Answers

SOURCE: Fan Noise on Dell Dimension 8100

All computer fans have a general design.  The name in front of "fan" really refers to the designation.  You'll see case fan, processor fan, CPU fan, cooling fan, etc.  In the case of CPU/Processor fan, some are sold with heatsinks (the metal block sitting on top of your CPU).

The first thing you want to do is make sure the fan is clean.  Chances are dust buildup is causing the excess noise.

If that's not the case and you're looking to replace the fan, then you first need to find out the size of the fan. General sizes(diameter X width in mm) are listed on this page:

Generally, you're looking for something that will match the size of what you're replacing & push enough air at a reasonable noise level to cool the heatsink/CPU.  You want to stay in the area of 30dBA max for noise.  You also want to see if it has a 3-pin or 4-pin connection.

For example, if you have an 80mm fan, I would suggest something like this:

It's pretty quiet with good airflow.  Also, it has a 3-pin connection, but includes an adapter for a 4-pin connection.


Posted on Oct 27, 2007

  • 781 Answers

SOURCE: Orange Light permanently on motherboard. PC won't start

1. motherboards for atx form factor pc's are powered even when the computer is off, particularly if you leave the computer plugged in to wall outlet... you better do not work on you computer while power cable is still connected to both, your pc and the wall outlet..

2. I found this thread that may be helpful, it may be the motherboard may have gone bad, cmos is corrupted or something may not be seated could also be one of these: Bad CPU, BAD ram, Bad power supply.. read the thread for details:

Posted on Sep 25, 2008

  • 998 Answers

SOURCE: Diagnostic Indicator

Beep codes and power LED status are pre-post errors. Usually beep codes indicate a problem with a memory module. Power LED is solid green for normal operation. Solid or blinking Amber color power LED indicates a power distribution problem.

Your responses are intended to improve the level of service provided. Please show your appreciation by rating your experience.
Thank You.

Posted on Nov 13, 2008

  • 564 Answers

SOURCE: Dell Dimension 5100 No Power No lights

Hi Eric,
Don't Worry we can fix this this problem.
This seems to be no power issue.
Just mail your email address and number to
Thanks, Prem

Posted on Mar 08, 2009

  • 16 Answers

SOURCE: Dell Optiplex GX280 Video Card Install Problem

You hit that one right on the dot.  ATI website showed the specs for that graphics card you installed as needing a 300 Watt power supply.  Good news though... I researched and I believe I found your 300W power supply.  There are 4 different Optiplex gx280 designs with 4 completely different power supplies.  Since you bought the low-profile video card, I believe you have the slim computer case and this power supply should work for you...

Good Luck

Posted on Jun 11, 2009

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

Cpu fan failure dell optiplex 360

Make sure the fan cables are plugged in on the motherboard. Or the cpu fan may have went bad and needs to be replaced.

Jun 24, 2014 | Dell Systems Dell OptiPlex 360 Minitower...

1 Answer

Dell optiplex 745 Floppy Diskette Seek Failure

how to solution. Dell optiplex 745 Floppy Diskette Seek Failure

Jan 20, 2012 | Dell Computers & Internet

1 Answer

Dell desktop optiplex 745 it builin vga card is not responced what i do?

If you think your vga card is not responding?? just try to insert another vga card in your expansion slot.
Otherwise you mean your computer have no display first try to switch on your pc and try to hear your computer fans are all working..if it is working just try to re install your RAM and u must clean it with a cloth.

Sep 04, 2011 | Dell OPTIPLEX 745 PC Desktop

1 Answer

Dell Optiplex 745 having all kinds of problems getting blue screens, but I can reboot and it works fine. I installed a new hard drive on this computer. I am not able to install the update for windows xp...


The main failure on the Optiplex 745 units are capacitors on the motherboard. When they fail you can get all sorts of strange problems - no boot, blue screen issues, no video or distorted video. Open your machine up and look for bulging capacitors on the board. Here is a link to a guide showing what to look for on the motherboard to determine if your problem is capacitor related or not.

If you do find bulging capacitors on the motherboard then more than likely that will be your problem. You can replace the capacitors and your board will be as good as new.

I hope this helps, if so please rate my solution.


Jul 13, 2011 | Dell OPTIPLEX 745 PC Desktop

1 Answer

AEG Competence B3101-4m oven not working on fan setting. Fan operates but no heat. Also intermittent problem on full grill setting. Any ideas?

Several possibilites come to mind.
first Has this AEG two fans if yes , it has a top and back fan, the element on the back fan sounds like its either a bad connection or blown needs further investigation, the intermittent grill possibly a thermistat, of poor contact on a connection again. Rear and top panel access, you may have to remove the top fan.
Hope this has been helpful

May 31, 2011 | Electrolux Ovens

1 Answer

Well i have a problem the fridge is working 100% but our freezer is not working right it is cold at bottom half but it is not working at top half like i put ice thing in it the water fast freeze tomoro...

If I read the manual right the red light indicator your seeing is the exlamation point above the fast freeze button. This is telling you that the freezer compartment temp is to high.

There can be multiple reasons for this:
1. Evaporator fan not running (Check fan by depressing door closed plunger for the light switch) The fan should be on and light off.

2. An unseen block of ice over the evaporator coils due to an automatic defrosting probelm. If you can determine that there really is ice on the evaporator coils, perform the manual defrost procedures I described in my initial response. If after doing this manual defrost things return to normal for a few days and then you see the high temp indicator again there is for sure and automatic defrosting problem.

3. Automatic Defrost Problem (Causes)
a. Defrost control failure
b. Defrost control heating element failure
c. Temp sensor failure or Bi-metal 60 Deg F thermostat failure

4. Condenser fan not running in the borrom rear of the unit. (Check to see that the fan is running by removing the fiberboard rear cover.)

5. Condenser coils blocked with lint (Check the coils when you inspect the condensor fan for operation.) Clean both the coils and the fan.

6. Thermistor failure (measures temp and has a resistive output) in the freezer.

7. Compressor not running (Causes)
a. PTC relay
b. Run capacitor
c. Conpressor failure

8. Compressor running but not cooling
Check to see that one of the copper lines line is hot to the touch. If it is not hot the causes can be low freon level, clogged freon drier, damaged capillary tube.

These are all the things that can cause your current symptom.

Thanks for choosing FixYa,

Mar 20, 2011 | Refrigerators

1 Answer

Dell optiplex gx280 desktop when turn on just orange light even fan not working, what is the prob?

Normally a solid amber light indicates there has been some type of hardware failure. Possibly power supply, possibly motherboard.

Here is a link with a few things you can try.

Feb 21, 2011 | Dell OptiPlex GX280 PC Desktop

1 Answer

My fan is Intermittently offf and on idk why is there something wrong in the fan or the laptop

Dear zidane_is_th
No there is nothing wrong with it. It is reacting to the heat build up in your PC. When it senses the temperature rise it will kick the fans on to help it cool down.
Just be sure and keep your vents from being covered so as not to hinder the fans when it needs to cool down. Overheating is the No.1 cause of failure in Laptops.
Like random shutdowns.

Hope this helps if it did just click the thumbs up

Feb 10, 2011 | Toshiba (K000016310) Cooling Fan

1 Answer

As with this gentlemen, after warm-up I get no warm air from the rear heater when either controlled from the front console or the rear. The front unit fan seems to be working poorly as well and flutters on...

most caddilacs have a filter under the wiper plate that filters out all the junk leaves and debris. first thing is to make sure the coolant is full, as the high temps make liquids dissapate. once you have done this, then I would check the restricted fan, or possibly the fan resistor, this resistor controls the amount of voltage to the fan and gives you multiple speeds.

Dec 31, 2010 | Cadillac Escalade ESV Cars & Trucks

Not finding what you are looking for?
Dell jt782 - Fan Assy Cpu Cooling, Optiplex 745, Usff Logo

Related Topics:

2,517 people viewed this question

Ask a Question

Usually answered in minutes!

Top Dell Computers & Internet Experts

Les Dickinson
Les Dickinson

Level 3 Expert

18389 Answers

Doctor PC
Doctor PC

Level 3 Expert

7733 Answers

mukhtar21 shaikh
mukhtar21 shaikh

Level 3 Expert

2017 Answers

Are you a Dell Computer and Internet Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides