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Anonymous Posted on Sep 18, 2014

CAN THE LIGHT BE TURNED ON IN THE ROOM WHERE THE TESTING IS DONE?

DOES THE LIGHT BEING ON IN THE TESTING ROOM AFFECT THE TEST?

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repair

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  • Contributor 22 Answers
  • Posted on Oct 30, 2014
repair
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Yes it affect all tje instrument calibration when it is turn on, and when you have patient test the result is afected because the patien has light for the bavk and he is not able to see all the diferents type of lights

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0helpful
1answer

We recently purchased a 2005 Acura TL, my daughter got in turned the key, alarm went off. Finally got that turned off now the car won’t go into gear, please help

Hi. Have you inspected anything yet or do you plan on performing the diagnostics and repairs yourself? You are going to need a few tools to remove lower dash trim, part of the center console and a test light to for testing. My first guess is a worn out brake light switch but that isn't the only thing that can break or wear out. Check the shift selector lever first. Sometimes coins or other belongings are laid upon the shifter and jam it. You will know by simply holding the handle and lightly try to move it forward and back (repeatedly). If anything is jamming it there will be zero play. If there is play you will easily feel the lever move back and forth 1/16". If that passes check for blown fuses. If they pass, Component testing will be next. I use a scan tool to observe some functions, look for ABS codes and a test light for testing. You will need the test light to test for power and ground at the brake light switch and shift interlock solenoid. Please write back if I can be of anymore assistance, Good Luck.
tip

How to test an LCD TV or monitor PSU and inverter

Hi.

Before proceeding I assume you have technical training along with the multimeter. A full testing must be done with power on, and for safety reason must not be done by an untrained user.

The tip contains only general indications. The reader is supposed to have the training to apply in practice the testing method below.

If there is no power at all, then the responsible is almost always the PSU.

When there is no power, test AC in to PSU. If there is no AC in (read volts, or read ohms on power cable), that means that the power cord must be replaced.

If there is AC in, then test the PSU section near to AC input. You always find a resistor or a fuse in there . Check if it has blown.
After that you test the rest of PSU component. If there is no power at all , and problem is not power cord, it is often possible to spot at a glance a leaky or bulged capacitor.

If there is power, but the monitor stays in standby, then te PSU is forced to low voltage only by controller board. This happens when a fault had been detected.

In this case testing the PSU becomes more complicate. The technician must locate the control lines from controller board. This control lines operate at lower PSU voltage (often +5V), and turn on higher voltages on PSU board.

The inverter may use for example a +20V line from PSU. The +20V line is turned on by the controller board, closing a +5V control line to PSU. When PSU is in standby mode, the technician testing the PSU must bridge the +5V line with the PSU low +5V circuit, and test if the +20V line to the inverter gets turned on.

As explained this kind of test must not be done by the unexperienced user, as the chance to waste the unit beyond repair is high, and there are also many safety concerns.

After testing the PSU, next part to test will be the inverter board.

The inverter is tested reading DC voltage in from controller board, and AC out to back light system.
The inverter is an high voltage board, remember, safety first when testing AC circuit.

If the inverter has no DC from controller, then test PSU, if PSU is OK, and inverter has still no DC in when PSU line to inverter is on, then replace controller board.
If the inverter has DC in, and no AC out, then replace the inverter.
If the inverter has DC in and AC out when higher DC voltage to inverter is turned on, then test at component level the main controller board, and if present test LCD controller.

Regards.
on Mar 03, 2010 • Televison & Video
0helpful
1answer

Had my Smart 4-2 mot'd Monday and it needed a suspension arm on the passenger side. This was done on Tuesday. Saturday morning the engine management light came on yet the car runs and sounds fine.

Very seldom does the check engine light being on affect the way the engine runs, so have it tested for the fault that turned the light on, It is called an OBD2 fault code test and is done with a code reader through the diagnostic data link under the dash.
1helpful
2answers

Not receiving messages

May be the signal is not good
3helpful
1answer

I cant get both switches to work properly one minute it turns the light on the next they done work. is the red wire suppose to hook up to the black screw

The key to three-way switches is the dark screw.
And different brands of switches put dark screw on different side of switch.

So, lets get out of this mess with a bit of testing.
You have two switches with 3 wires on each switch for a total of 6 wires.
Take out both switches and separate wires for testing.

Turn on power and test each wire to bare copper wire.
One and only one wire will test Hot.
The hot wire goes to dark screw on switch1.
The other two wires in that box go to either screw on switch1.
One switch done, one switch to go.

Move switch1 lever to down position.
Turn on power and test 3 remaining wires.
One wire will test hot. Mark this wire.
Move switch1 to up position, and test 3 remaining wires again.
A second wire will test hot. Mark this wire.
The 2 marked wires attach to either brass screw on switch2.
The third wire attaches to dark screw.
Both switches done.

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0helpful
1answer

Infared won't work unless room is brightly lit

Just to provide clarification regarding the IR remote control- unfortunately its the opposite. A brightly lit room can negatively affect the infrared signal the remote uses to transmit the signal from the remote to the receiver- additionally interference may also be caused by fluorescent lighting. Another recommendation regarding IR signal interference is to; power everything off but leave the receiver & your TV on. Then proceed by powering one component on at a time, then testing the remote after each component has successfully been turned on. This process will also help you determine if a component may be causing the interference. Hope this helps! -Kirstie DISH Network
1helpful
2answers

I have a 2005 buick lacrosse. The low beam headlights have stopped working again(2nd time) The first time, even though the warning light was on, nothing was found wrong in the system. The headlights just...

https://postimg.org/image/agdjusdgl/

Click on the link. What testing have you done. Did you check for voltage and ground at the lo beams? Use a test light. In the diagram, the top wire for low beams is voltage, the bottom wire is ground. There are lo beam fuses, check those. Check voltage at fuse with lo beams turned on. It might be possible to unplug the low beam relay and use proper jumper wire on proper terminals to see if lo beams will operate. If they operate with the jumper but not w/o, check the control side of relay.
Your head lamp switch and dimmer are both inputs to bcm. I can only help with testing. You have to do the testing.
2helpful
2answers

All of a sudden, there is no light on the button. I have check the electric outlet, it is OK. I pushed every button, but it doesn't work. Is there a fuse on my washer? Or anyother problem?

There should be a dedicated circuit breaker in your main panel.
Check that first.

Then verify power at the outlet with a multimeter.

If there is power at the outlet - unfortunately, there is internal damage to the main board (typically from a power surge) and further testing is required.

Thanks!
0helpful
1answer

It's taking 2 or 3 times to fully dry my clothes! even on small loads

HI, Check the following to address this issue further.

Note: Normal drying time for a dryer is about 45 minutes (some may take up to an hour).

1. Venting
Make sure the dryer vent hose, as well as the rest of the vent duct, is not clogged.

Unless regular maintenance is performed, chances are there is a lot of lint accumulated inside the dryer. This might affect the drying time and could be a fire hazard. Make sure to have your dryer cleaned regularly. Because this might involve taking most of the dryer apart, it is recommended to have a qualified appliance repairman perform this task.

2. Thermostat
There are a couple of cycling thermostats inside the dryer. If one of them breaks down, it might affect the dryer's performance. Replace the defective thermostat. These thermostats are located in the dryer vent duct and sometimes mounted on the blower assembly as well.


Thermostat Testing Procedure:

HI. To test the thermostats or fuse, set the multimeter to the ohms setting X1. Touch one probe to each terminal. You should get a reading of either zero or infinity. At room temperature, the thermostats should have a reading of zero. When the thermostats are heated to their limit temperature, they should switch off and you should get a reading of infinity. The fuse should be tested at room temperature for continuity.
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