Posts Tagged ‘problem’

Diagnosing Dell OptiPlex touchscreen problem

Sunday, January 3rd, 2016


Slightly strange but logical one. We recently used a Dell E2014T 20 inch E-Series Touchscreen on a job. Worked fine until we got it on site and then the screen’s touch accuracy went haywire. On-screen buttons didn’t activate and some areas of the screen caused the touch area to seemingly warp and cause false cursor positioning.

We noticed a slight pattern to the ‘warping’, mostly to the left but also in a strange diagonal. We fired up a paint program and drew lines across the screen to reveal the distorted areas. The ‘ah-ha!’ moment was when we realised the screen was an optical touchscreen. The ‘OptiPlex’ system uses a series of infra-red lights and detectors located around the edge of the screen. By placing your finger on the screen, it breaks several of the beams and your finger’s location can be triangulated.

The distorted lines you can see in the image above is evidence of the screen going ‘wonky’ along definite diagonals. On closer inspection, there were small specs of sawdust in the screen border. A quick squirt of compressed air and the screen was back to normal.

Also, if you’re planning to use this monitor (or a lot of low-cost touchscreens like the the Mimo Magic Touch series) on a Mac, you’ll probably have a issue finding a driver. Apple just don’t seem to support any touchscreen standards. The only 3rd-party drivers we’ve managed to get to work are from Touchbase. They cost money but it may be the only option.

BMW F650GS rear brake keep seizing? Try this…

Sunday, August 7th, 2011

Sticking Brembo master cylinder

Seems all my bikes are being blighted by brake issues. While the Ducati has reassuringly unpredictable electrical problems, the BMW has reassuringly German, old-fashioned mechanical problems.

So the symptoms were pretty simple. The rear brake jams on after a few miles of riding. Just happened out of the blue while commuting to work one day. Being a bit of a MacGyver type, I got my house key out and wiggled the brake pads back a bit. Wasn’t easy, especially as the brake was red hot from the friction. Took 10 minutes but it seemed to work eventually.

The rod that the pads slide along looked rusty so I assumed the winter road salt had done its worst. Same happened on the way home. So back at home, I stripped the brake caliper, regreased with copper grease and reassembled. Same happened the next day so that didn’t work! BTW. The rear caliper isn’t actually bolted to the swingarm. It sits on a free-floating ‘peg’ on the swingarm and is simply held in place by the brake disc running between the pads. So if you’re looking for the bolts to remove the rear caliper, you won’t find any. Just remove the rear wheel and the caliper falls off by itself.

I also adjusted the push-rod that connects to the Brembo master cylinder from the rear brake pedal. Same issue happened. I even took it off, bled all the brake fluid. Disassembled the Brembo cylinder, greased the internals checked the spring blah, blah… no joy. TIP. If you need to bleed the brake fluid and you have the ABS model, you need to rotate the rear wheel to push the fluid through. Took me ages before I realised.

As usual, online forums were full of confusing advice, as they were solving someone else’s problem, not mine. I have the ABS version, so lots of chat about the ABS sensor having issues.

Cutting to the chase, it WAS the Brembo master cylinder, but it needed a new one to solve the problem (or a rebuild kit I guess). It was as simple as the piston not quite returning to the resting position. The image above shows the ‘sticking’ one on the right and you can see the black piston is 5mm or so lower than the new one on the left. Therefore the brake fluid was being ‘pushed’ by the lever, but then being held there. The pads then stuck on, causing friction against the disc, causing heat, making the fluid expand, binding the pads even tighter. Explains why it took me 10 minutes of ‘fiddling’ that first morning before the brake worked again. It was the fluid cooling down and releasing the pads all by itself.

So I ordered a new master cylinder (they’re fitted to loads of bike models). Making sure I had the ‘in-line exit’ version (as the fluid came in from the side and out from the top… in-line with the body) and the slightly bigger piston version (13mm rather than 11mm) for more oomph. It’s part number 10.4776.60 so google “Brembo 10.4776.60” and you should find one. I got one from this page on for £43. Putting the old and new one side-by-side, it was immediately obvious the piston (the white ceramic looking thing) wasn’t returning to the starting position against the circlip/washer like the new one did.

Bolted it on, new fluid (making sure to pump it through by rotating the rear wheel). Problem solved! Been riding it for 2 months, no sign of any problem.

There was some chat online about needing a special tool to bleed the ABS internals as air bubbles would cause it to malfunction, but I didn’t have any problems. Tried it out a few times and works fine.

So, as usual, bodged my way to another fix. Hope that helps if you were having similar problems!

Ducati 748 brake light stuck on? Try this…

Sunday, August 7th, 2011

Just thought I’d share the latest fix for another classic Ducati intermittent fault.

I’d been having a few electrical problems, but tracked it down to a dodgy loom connector. Lots of stuff was going mental, lights were coming on, rev needles were moving by themselves. Replaced the loom. Sorted.

But some extra problems are still hanging about and I’m never sure if the loom may still have a dodgy connector. One problem was that my rear brake light would stay on. But not always. Grrrr! Mostly when I started her up, the light would be permanently on (like I had the brake pressed). I’d go for a ride and when I got back, the brake light was working normally. Maybe 40% repeatable.

Looked online and lots of chat about microswitches needing replacing, losing a dowel rod and foot brake sensors needing replacing. I wiggled everything in a half-arsed attempt to track it down. No joy. I disconnected the rear brake sensor (there’s a really obvious connector just above the clutch cover). The light stayed on. Must mean it’s the front brake somehow.

I turned my attention to the tiny microswitch behind the front brake lever. It had no obvious connector so I assumed it plugged into the headstock loom, which needs the front of the bike disassembling to reach. Not fun. I squirted it with WD40. Pressed it loads. No change.

I decided to unscrew the microswitch to check it. There are two tiny flathead screws and even more fiddly bolts at the back. Make sure you dont lose them! After removing it (brake lights were still on), I pressed the microswitch… brake lights went off. Eureka! Turns out the microswitch had moved maybe 1/10th of a mm back and now didn’t work. The switch’s natural state is on. You have to press it up against a little push-rod that connects to the lever to activate it… and switch the lights off. Confusing I know. When you pull the brake lever, it push-rod falls away (as there’s no brake lever pushing against it) and it deactivated the switch… which goes to it’s normal ‘brake light on’ state again. Makes sense I guess.

Anyhoo, long and rambling way of saying I simply reseated my microswitch a hair’s width closer to the push-rod / lever and it was enough to press the microswitch (turning the brake light off). Don’t move it too far in though, as it will require the brake lever to be pulled in a fair way before the rod has moved back far enough to deactivate the switch (turning the light on).

May not sort your problem out, but it’s definitely something to check.

iPhone OS 3.0 GM SEED install error -9807

Thursday, June 11th, 2009

Just installed the iPhone OS 3.0 GM seed file onto my iPhone 3G from my iMac. I’m part of the iPhone Developers program so the ‘seed’ means ‘pre-release’, as the official update isn’t due until the 17th June or so. So slightly excited and nervous just in case something went wrong.

So, initially all went well. Process was something like this…

  1. Download the .dmg disk image
  2. Open it to view the .ipsw file
  3. Fire up iTunes, select the iPhone
  4. VERY IMPORTANT: **Backup the phone** You may need the backup data later!!!
  5. Option-click (alt-click) the ‘restore’ button
  6. In the dialogue box, locate the .ipsw file
  7. Wait for it to do its thing and restart the phone
  8. Restarted iTunes… PROBLEM!!

The iPhone had a ‘connect to iTunes’ diagram on it’s screen and wouldn’t go any further. Like so…

Restarted iTunes then it threw an error…

“We could not complete your iTunes Store request. An unknown error occurred (-9807).”

This can happen with the iTunes store and keychain errors, so I repaired my keychain. No change to the error though.

The iPhone was visible intermittently in iTunes but had no options or content listed under the icon, even right-clicking it just displayed ‘Eject’. Tried restarting both Mac and iPhone. No joy.

Finally tracked it down to a permissions thing. Luckily, I had a few user accounts set up on my iMac, so I logged out of mine and into another. If you don’t have them, then set one up from the System Preferences/Accounts panel. Fired up iTunes in the other account and the iPhone sprang to life! Yay!

Then I logged into the main user account again, fired up iTunes again and everything worked.

I then noticed my data hadn’t actually migrated back during the update (apps, prefs, photos etc.). Thank god for that backup I just did (see above). So I then restored to the backup. This restores the data, not the OS, so I still have OS 3.0 etc.

I then had to manually synced the Applications back (as I had them set to manually sync anyway) and it finally looks like it was supposed to!

Had a quick play and all my emails are there, text messages intact, contacts, ringtones, apps etc. Had to move my apps around the screen manually to tidy them up but apart from that all good.

Hopefully this won’t happen to the public release but hope this helps if you do need it.


Just found this entry that may help. If you’ve got Little Snitch running on your Mac, you may be seconds away from the answer!

YouTube problem solved…

Monday, December 1st, 2008

I’ve been blighted, as have many others, by YouTube video appearing blank and simply stating “We’re sorry, this video is no longer available.”.

There have been a couple of suggestions, like restarting your router, hard coding your IP, using an IP tunnel application, turning of Google Web Accelerator and so on. Some suggested it was a YouTube caching issue or an IP problem but it was also a bit random. My own Ducati Exhaust video stopped working while my Halo Soundtrack video was fine. When I’m at work, some of the videos that work at home failed, and vice versa. I use a Mac at home and a PC at work. Both use Firefox but all browsers seemed to do the same thing. All-in-all verry confusing.

However, it turns out it’s none of that. I’ve just updated my flash player from to and all’s well again. While I’m happy it’s all working, it’s also a little worrying that the big media owners and entertainment portals are so reliant on something as ‘simple’ as a Flash version issue.

If I was YouTube, I’d make this solution visible on the homepage (that’s if anyone actually visits the homapage). I’m supposed to be clever and if it escaped me, it’ll be escaping a fair few others. My impression of YouTube was suffering if I’m honest, thinking they’d become too big for their architecture to cope with.

But now I can check out all those vidoes of kittens again. Karma restored.

How to remove the front panel from a Samsung RS series fridge

Monday, September 29th, 2008

Here’s the latest in the series of my “I fixed it and here’s how I did it” articles. This time it’s a Samsung RS21JGRS fridge freezer. The ice dispenser ‘flap’ came loose and stopped the ice coming out. Quick search on t’internet didn’t yeald much so in the spirit of sharing, here’s how it’s done. This is also the way to get to the water nozzle, change the face plate etc. and is relevant for most RS21 models I guess.

You should also know I’m not a freezer engineer, this will mess with your warranty, I’m not liable for any damage or harm you cause etc. Use this as a guide, what you do with it is up to you. The photos below show the electricity being on… you should probably switch yours off! It only takes 10 mins or so to do the whole procedure, so nothing will defrost in that time. Remember, safety first kids!

Step 1: The freezer door of your fridge/freezer should look something like this… with water dispenser on left and ice on the right.

Step 2: First up, push the tip of the water tube backwards to release it from the plastic housing. It kinds pops out but don’t push it too far back, it’s just to release it.

Step 3: Use a blunt, fat screwdriver blade and insert it in any of the two slots under the main faceplate. It’s important the screwdriver (or other tool) isn’t too sharp or scratchy as it may mark the main fridge surface if it slips. Very gently but firmly, lever the panel outwards (pull screwdriver handle towards you). It should make a loud pop as the tabs let go. Try not to twist the screwdriver as this may cause small dents in the plastic. It’s a bit disconcerting at first but it does work.

Step 4: Work your way around. There are four on each side. See the image on step 6, the notches are there the ‘pops’ that should happen.

Step 5: Wiggle the panel out. There is an electronic connector at the back with a clip holding it on. Lever up the clip and push the connector apart. This will separate the panel completely. Put it somewhere safe.

Step 6: Should look something like this…

Step 7: Undo the two (maybe three) screws holding the plastic panel in place and hinge it out as shown. You can unclip the wires if you like, but you really don’t have to with this technique.

Step 8: To get the panel out of the way, I taped it to the handle…

Step 9: The ice flap has a long hinge pivot on the left and a short on on the right. If you need to remove the flap, push the right side towards the left (or prise it with the big screwdriver you used earlier) to free the right-had pivot.

Step 10: Once free, pull it towards you a little and to the right to release the longer left pivot. Watch out for the little spring thing. Put your finger under it to stop it going ping. Be careful to pull the flap directly towards you once free, as the funny white lever on the left hand side needs to slip out of the hole without snagging.

Step 11: Flap removed…

Step 12: And finally: When you reassemble, you have to be careful to do three things at once while refitting the flat. First, put the funny lever on the left in the hole. Second, make sure the spring lever is pulled back and has some tension on it… and is to the left of the slight fin on the roof of the housing. Lastly, make sure the left pivot (the longer side) goes in first. Once you have all three checked off, just push in the right side to engage the right pivot. Job done! Now assuming you’ve switched off the electricity, you may notice the strange lever on the left won’t go in the hole. This is the delay mechanism you hear after it dispenses ice. It will only release when there’s power and the microswitch on the panel has been activated (i.e. when it’s all back together again). If it stays out as pictured, just push it upwards to release the ratchet thing and the flap should pop back flush to seal the hole.

Parts: If you need to replace the flap, it looks like this…  Part # DA63-00410A and are about £10. Last place I found one was in the Netherlands here.