TideLog Posts Tagged “fix”

I had the misfortune of my tablet getting damaged this week. I was working in Rikku’s bus garage, with it resting on the bus’s bumper crossmember taking readings from the ECU, when Rik called me away. While I was away the vibration of the engine caused my tablet to fall off, straight onto tarmac! Luckily the screen hasn’t cracked.

I’ll show you all how to replace the digitizer, as it’s a lot more straightforward than also having to replace the screen, as less disassembly is required.

A. Removing the SD card cover/Wi-Fi antenna

First of all, your digitizer is GLASS, so you can use sellotape across the glass to hold it in place, preventing any injury, or shards of glass falling on the floor. Removing the damaged digitizer will stress it and maybe cause more damage as you do it. The glass provides 90% of the front frame’s strength, so once broken it loses most of its rigidity.

Once you’ve secured the glass, turn your tablet over, and remove the SD cover, which also doubles as a WiFi antenna, by locating the notch on the left, and lifting up. It unsnaps quite loudly, but be gentle. Once removed, place in a safe place:

2-removing-SD-cover

B. Removing the rear casing

Next up we’ll be removing the rear case, which is easy to do as there’s no screws, it’s all clipped together. A lot of the reviewers of the Bush MyTablet reckoned the aluminium back was just cosmetic, but it is actually structural, and gives the tablet weight and strength to prevent flexing of the whole body to protect the internals,.

Using a flat blade jeweller’s screwdriver, unsnap one set of clips between the front digitizer frame and the rear case, and then use a plastic spudger to do the rest. DON’T use a screwdriver permanently, only to get a start. Note in my picture below, the lip of plastic on my rear case near the headphone port was damaged on mine in the impact, so I used this as an easy access point for my spudger:

3-unclipping-digitizer-from-rear-cover-1

Continue all the way round the case, and don’t worry about snapping noises. The screen is clipped to the backside of the digitizer, but as long as you are gentle, it won’t resist too much, and you shouldn’t break anything. The glass may crack and crunch on the broken digitizer at this point, due to the lost strength I mentioned earlier. I didn’t use tape on my glass as I was on a disposable cloth I could just throw away:

4-unclipping-digitizer-from-rear-cover-2

Once you’ve unsnapped all the clips, the rear case will just lift off. There’s nothing attached to it, so just lift it clear, upon doing so you’ll see the wonderous internals of the tablet, including the relatively large battery, and small mainboard. You can also see how the aluminium back actually constitutes most of the rear cover, with the plastic just being a small frame, proving my point about the strength the metal back provides:

5-lifting-off-rear-cover

When you remove the back cover, WATCH out for the power and volume button pack dropping out. It isn’t plastic welded or screwed onto anything, so it’ll just fall free:

6-watch-out-for-volume-and-power-buttons-falling-out

C. Screw and connector locations

Now comes the preparation stage of locating the connectors and screws you’ll need to remove. If you’re just removing the digitizer, there’s 2 screws and 2 ribbons to remove, but if your screen is broken most of the internals have to come apart as the mainboard and battery are mounted to the back of the screen panel’s chassis with tape and glue, both of which are surprisingly strong!

7-screw-and-connector-locations

The ribbon cable connectors for the digitizer and display are under the tape on the left and right sides, respectively, which I’ve labelled in red, the two red circled screws attach the PCB to the digitizer frame. The battery and speaker cables are under the orange tape on the bottom left. These two are soldered in, but don’t need to be de-soldered at all unless you are explicitly replacing them. Even for a screen replacement, desoldering these isn’t necessary, they can just be lifted out the way. To remove the battery for screen replacement, simply break the glue holding it in, and lift it out of the way after the rest of the disassembly is done, leaving the wires soldered in. Don’t do it yet, you’ll end up with a tangle!

The connector flaps for the ribbons need to be flicked upwards NO MORE than 90 degrees VERY gently. If you snap the flap, the whole PCB socket is ruined as the flap provides the torque to hold the ribbon in place, pressing the metal contacts together. Taping it back together is not good enough. DO NOT rush, the same goes for the left one. This is where unskilled amateurs make the jobs more expensive, take it from a professional who has fixed mistakes many times! Modern electronics are VERY delicate, and need eagle eyesight and jeweller’s finesse, shaky hands just won’t do!

From the left, lift the silver tape a little (DON’T damage or discard it as it can be re-used), and remove the ribbon for the power/volume buttons. Lift the flap gently, then ease the cable out.

10-power-and-volume-switch-ribbon-connector-location

From the right, lift the black tape. If you’re going to be replacing ONLY the digitizer, remove just the top ribbon that I’ve circled red, which is the digitizer cable, using the same care as for the power/volume ribbon above. If your screen is cracked, you’ll need to remove the bottom one as well, which is your display cable that carries display signals, and the backlight power.

Again, I can’t stress enough, DO NOT rush, and DO NOT force the socket connector flaps over 90 degrees, if they break you’ve just made the job 80% more expensive as you’ll need the sockets replacing, or a new PCB, which will involve data recovery off your old board, especially if you damage the touchscreen connector!

11-digitizer-ribbon-connector-location

D. Removing bottom frame support

Where the speaker is along the bottom you’ll notice a plastic frame screwed into place. This is like a strengthener and support in one unit, it holds the speaker in place while giving the bottom of the digitizer some strength. It also carries clips that the rear cover was mounted to, so I consider it a main structural member of the whole tablet chassis. Simply remove the two screws, and lift it off the digitizer. Watch out as the speaker is now loose on its cable and will slide around!

8-screws for-frame-support

E. Removing screen & mainboard assembly from digitizer

If you look all around the inside of the frame you’ll see lots of clips holding the screen in place. We’re now going to remove the screen VERY GENTLY. This is another step that you should take your time, there’s no medal for rushing it, as you WILL likely break your screen if you do it wrong, the glass on the screen is thinner than the digitizer. That’s the reason tablets have their digitizer separate to the screen, mounted half an inch away.

If your screen and digitizer are already broken and you’re replacing them both, I personally would still be careful, because I’m a professional, and normally it’s someone else’s equipment, which I respect 🙂

9-clips-attaching-screen-to-digitizer-frame

So, while unclipping the clips (they may be stiff) you can use a spudger to keep the screen from re-clipping itself in, but DON’T overdo it, don’t lever the screen too high with too many clips still securing it, it will flex and break. Obviously if your screen is broken and you’re replacing it this isn’t relevant, but still take care, because I would 🙂

The image below shows me using my spudger as the clips are unclipped, my screen wasn’t damaged before, and it wasn’t damaged after, apart from a scratch on the glass caused by the digitizer imploding on impact!

12-unclipping-screen-clips-while-lifting-screen-GENTLY

Finally, once that’s all done, you can separate the digitizer from the rest of the chassis, and pat yourself on the back for getting this far without any major damage, unless you DID damage something I told you not to, in that case it’s your fault for not listening to a pro, take yourself off to the naughty corner and think about what you’ve done!

Otherwise, if all went well, you’ll end up with the tablet looking like this:

13-chassis-and-digitizer-separated

Re-assembly with a new digitizer is the reverse of removal, if you remember my advice you should have a fully functioning tablet that acts as if nothing happened once it is rebuilt!

F. Extra steps for screen replacement

I only had to replace my digitizer, but if your screen is damaged as well, once you finish with the separated digitizer as step E, you’ll need to:

  1. Remove the display cable connector as I mentioned earlier
  2. Separate the battery from the screen back by removing the glue. When you reassemble the battery onto the new screen, use *new* adhesive strips instead of glue to secure it, as you don’t want it rattling around, its metallic case can short stuff out, which you DEFINITELY don’t want happening.
  3. Remove all the tape strips holding the PCB,
  4. If you’re also replacing the battery, desolder the battery cables, making sure you note the polarity. Resoldering the cables the wrong way may short the board out, and cause an expensive mess. I don’t know if the Chinese electronics in these have decent short-circuit protection, and I’m not willing to find out!
  5. Re-assembly, again, is the reverse of removal. With new parts, TAKE EXTREME CARE, you don’t want your new screen or digitizer damaged again! And make sure all the tape is replaced and secured in the original places. Mark out where the strips sit with a marker pen.

Good luck!

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The release of Project CARS was huge, but there are a few niggling issues with it. As it uses a much improved version of the Madness engine found in Need For Speed SHIFT 1 & 2, the experience is massively improved, but as the game was mainly designed with wheel and pedal touting PC users, the controls on the console versions can seem a little touchy. Here’s some settings to help you get the most out of it:

At your driver dashboard, press your menu button (the one with the three lines), go to Options and Help in the menu that appears, then controls, and tab across to the configuration page. You’ll see lots of possibly scary looking sliders depending on your skill level! Don’t worry, use this guide to help:

Method 1:

Throttle Deadzone: 0%

Throttle Sensitivity: 30%

Brake Deadzone: 10%

Brake Sensitivity: 15%

Controller Filtering Sensitivity: 50% (you should try different values to see what you like best). A higher value means smoother (less twitchy) steering but it can cause input lag.

Steering Deadzone: 5-10% (it depends on how worn your left stick is, 5% seems fine to me, but experiment as your car may pull depending on stick wear)

Steering Sensitivity: 0

Speed Sensitivity: 60-65% (this setting allows for small corrections, it basically makes the wheel less sensitive, especially on the straights)

These settings should make the game much more playable, and the steering less twitchy. You may need to further adjust it for different types of cars, but have a play, you can’t break anything as there’s a “reset to defaults” option on the controller settings page 🙂 If that still doesn’t feel right, see below:

Method 2:

a. Set all sliders to 0. And I mean everything, throttle, brakes the lot.

b. Turn off advanced settings.

c. Then just turn speed sensitivity up to 80.

Method 2 works out the best way for me, method 1 felt like the controller didn’t centre coming off the steering, the car continued to drift slowly in the direction I’d come off when the stick was straight. The brakes were also too bitey and the steering was still too twitchy with some cars, especially the Karts, Method 2 has made me feel in control again!

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Electric showers are great, but they do go wrong occasionally. At Kitamura we repair all types of showers. A lot of people seem to confuse “power showers” with “electric showers”. They aren’t the same. An electric shower simply heats the water, the water goes through the shower under simple water pressure itself. That is where power showers differ. They still heat the water, but they also have a motor assisted water pump, which acts like the turbocharger in an engine, where a little amount of pressure is converted into massive pressure by an impeller.

We recently got called out to a faulty Mira Essentials electric shower. These were made in 2000, and this one was suffering from random pressure drops, and weak output. Here’s a shot of under its cover, I’ve labelled its parts which I’ll explain below:

Electric-Shower-Components

A. Water input w/filter

The cold water input, with filter. This is a gauze filter that filters any silt in the water. If not filtered out it could collect in the water heater, and cause failure, or blockage in other parts of the shower system.

B. Water impeller.

This is not electrically assisted as in a power shower, but it helps to keep the shower running if there is momentary pressure drop due to something else being used in the water system like a tap.

C. Power and Temperature knob with flow solenoid

This is the ON/LOW/MED/HIGH selector, which works in tandem with two microswitches, and two heating elements. When the shower is switched on, the electric flow solenoid opens, allowing water flow. In the LOW position the water heater is fully switched off, and the water is cold as all microswitches are open. In the MED position, one microswitch is closed, so one of the elements is active, and in HIGH both switches are closed, making the heater operate at full wattage, in this case 4.2kw.

D. HIGH microswitch

This is the microswitch that operates the second element by turning the temp knob to HIGH as above.

E. Temperature knob.

This works by varying the amount of water that gets through to the output. By reducing the speed of water flowing through the heater, it makes the water hotter, and increasing it makes it colder. If the Mode selector is HIGH and the Temp knob turned all the way to HOT, the heater would be shut off by the TCO (Thermal CutOut) on the heater as the water temperature is too high, which will cause scalding to the person using it, and also damage to the heater.

F. Neon indicator PCB

This board contains the neon indicators for Power, Overheat, and Low Pressure. It also contains resistors to prevent premature wear of the neon bulbs, they are run from 240v and don’t last long, especially the POWER indicator, as that is on as long as the mains is on.

G. Mains input terminal block

Self explanatory, this is where the mains is wired in to the shower. In this case the shower had its own switch and fuse in the consumer unit, so we didn’t have to turn the electricity off to the customer’s entire house while we worked!

H. Water heater with TCO (Thermal Cut Out)

Here’s where the water is heated before going to the shower head. The two elements are individually controlled by the microswitches previously mentioned in C, controlled by the MODE knob. The heater contains a thermal cutout so that the elements are turned off if the water gets too hot. Once the water reaches a certain colder temperature, the thermal cutout switch turns the elements back on.

The thermal cutout is normally only activated if the temperature knob is on HIGH, and the TEMP knob set to its hottest, which is minimal water flow, as mentioned in E.

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I’ve had this problem a few times on my laptop. It occurs mostly when the power suddenly goes off and it switches to battery. You lose all capacity monitoring, and can’t tell how much is left. The system tray icon changes to this:

no battery detected

Microsoft’s forums are hilarious. Their “Most Valuable Professionals” give the funniest canned cut ‘n’ paste responses, from, “Your power driver is corrupt” to your “Windows needs reinstalling!”. I know exactly what causes it, and it ain’t anything to do with “power drivers” or corrupt Windows. It’s the little monitoring chip in the battery. Like a lot of integrated electronics, it sometimes gets confused. Sudden switchovers from mains to battery tend to cause it, especially if there’s any surges from the battery as it kicks in.

The age old advice of “Reboot!” is the wise advice. If that doesn’t cure it, turn your machine off, remove the mains and battery, and hold your power button down to discharge the circuitry in your device (apart from the RTC circuit, but this doesn’t matter), that should cure it. Removing the battery opens the circuit to the sensing system in the battery, and resets it.

Simples. I hate MVP’s, they go on a 5 day course and think that gives them a Professional title? I’ve done MVP courses, but have the skills and years of software and electrical experience to further and back them up

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I repaired a Luxor LUX-19-822-COB 19″ TV/DVD Combi unit for Greg’s aunt and uncle recently. It is a Vestel, and uses both a 17IPS16-4 combined PSU/Inverter unit and a 17MB46 mainboard. According to Greg, and his aunt & uncle, there was no sound or picture. It turned out there was sound and picture, but no backlight. Inserting a DVD made the TV start the DVD software, and the DVD began playing. There was sound and a faint picture on the screen. All voltages coming out of the PPSU section were present and stable, the TV was running quite happily, albeit with no backlight.

So the power supply was sitting in standby, all main voltages off. Pressing the Power button was bringing the PSU into full On mode, and the voltages were nice and stable, as they should be. This proved the TV’s MCU was interpreting the ON signal and pulling the PS_ON pin high, and the PSU was starting correctly. The DVD module would have shown if there was any failure on the voltage lines as it wouldn’t have accepted the disc, and would have been sluggish or appear dead. The TV wouldn’t have even booted to the DVD Software if the drive wouldn’t start, which I believe is stored on the DVD drive’s Micron EEPROM on these drives, it isn’t part of the TV mainboard.

Vestel-17IPS16-4-PSU

I connected two laptop backlights to it, they flickered then went out, there was no “2 seconds to black” symptom, or red tinge, it was a “blink-and-you’ll-miss-it” scenario. Connecting the TV’s screen lamps up to a laptop inverter revealed they were fine, with no ignition lag or red/pink tinge, so my diagnosis had narrowed the fault down to the Inverter/PPSU unit. Due to not having my oscilloscope or capacitor tester handy, I ordered a new PSU/inverter board, which will be fitted soon. I don’t know what the actual fault is with the original supply, but I will be repairing and re-using it. I’ll update this post when I do repair it. Here’s the TV with the cover removed, you can see how it all fits together:

Luxor LUX-19-822-COB-cover-removed

Another PSU/inverter combi unit that made life easier for me, due to it not doing the protection shutdown feature of separate inverters, where the inverter sends a signal to the TV’s MCU that it has a fault, this then causes the MCU to either not start the TV fully to software boot stage, or to shut down into protection mode if started. Combi PSU/Inverter units do make diagnostics easier, as the TV still starts if the inverter, well, doesn’t 🙂 If the whole TV doesn’t start, the PSU section needs to be looked at, you might have flaky fluctuating voltages coming out of PL804, the L shaped section of pins that connect to the mainboard. Here’s an image I made showing the pinouts of the 17IPS16 connector, the mainboard connector, and the DVD module connector, click it to view it full size:

Vestel17IPS16 PSU Voltage schematics pinoutPlease note, this is my image, I created it using a schematics drawing program, so please don’t distribute it. If you reference it on a forum, please link to it, don’t copy it or modify it.

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