Archive for the ‘How to’ Category

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.

Fix for “Vehicle details could not be found” on the DVLA vehicle lookup. Maybe…

Saturday, November 28th, 2015


Another random ‘how to’. I was recently trying to check what date my Ducati needed its road tax and MOT. I went to the DVLA Vehicle Check site at, entered my reg and make (it auto completed “Ducati”) but received the following:

Vehicle details could not be found

Vehicle details could not be found as it has not been possible to locate the vehicle details, your enquiry cannot proceed and has been cancelled. If you want to check the vehicle record held by DVLA…

Tried another vehicle I own and it worked fine. It just didn’t like the Ducati for some reason. Decided to try a few other sites that seemed to refer to the same database. The MIB at least managed to tell me it was insured. It was a start.

Then I went to at . It’s a paid service but the first step is free and just verifies they can locate the vehicle. On entering my reg number, it returned:


We have information on our database regarding [REG NUM], a Ducati 748bip-98 (Motorcycle). Check before you buy. Choose a check to proceed.

The interesting bit was “a Ducati 748bip-98 (Motorcycle)”. It seems the DVLA have mashed up the make and the model in their ‘make’ field in their database. Where others just ride a Ducati, I seem to ride a Ducati 748bip-98. Snappy!

Back over the the DVLA site, I entered my reg and “Ducati 748bip-98” in to the make box and it worked!

If this is happening to you, you may want to give it a try.

Mac Firefox only connects to HTTPS sites? Got Little Snitch? Try this..

Saturday, December 6th, 2014

I hadn’t used Firefox in a while and needed to do a bit of cross-browser testing. I fired it up and got a strange and seemingly random error where it wouldn’t connect to some web sites. Just got an “Unable to connect” error page.


I quickly worked out that it ONLY allowed secure sites to load, anything with https:// at the beginning. Did the usual Google search but got a mixture of Windows solution saying turn off anti-virus or Mac solutions where people cold only connect to non https sites. Hence me writing this post, just in case you’e going through the same process.

I have Little Snitch installed, which allow you to selectively allow or deny network access as and when they happen. You’ll be surprised at how much applications constantly send to and from their servers! Anyway, it was Little Snitch blocking traffic on port 80.



Not sure why there was rule in place in the first place as it shouldn’t need one for top-level access, so they could be deleted.

And now it works. Hope it helps you out!



Guide to replacing a BMW E46 4 cylinder pre-cat sensor

Monday, December 2nd, 2013


Did a bunch of searching online for this when mine broke and couldn’t really find anything that related to the 4 cylinder E46 BMWs. Got a good steer from the good folk over at Bimmerforums so thought I’d share the full process in the hope it saves you the same journey.

The problem:

I have a 2000 BMW 316i SE 4 cylinder. The engine light came on and I checked the error codes using my Peake R5/FCX-3 reader. This plugs in under the dash in the ODB2 port (or in the engine bay on pre 2001 cars with an adapter) and came up with a single code ‘A6’ which reads in German as “Periodendauer Lambdasonde vor Kat” … and translates as “PreCat oxygen sensor”. In normal speak, the exhaust sensor just before your catalytic convertor is faulty. Thinking about it, the engine did seem a bit sluggish and sometimes stuttered at low revs when parking and would sometimes ‘dip’ during initial acceleration, especially from low revs or up a hill. Some form or fuelling / management problem would explain all of that.

The science:

The oxygen sensor (also known as a lambda sensor) tells the engine management how to alter the fuelling based on what gases are currently coming out of the engine. It can sense too much unburnt fuel and then reduce the intake mixture and vice versa.

4 cylinder cars (316 and 318 models)

There is a sensor before the catalytic converter (pre cat) and after (post cat) on the 4 cylinder BMWs. They are located under the car and can be clearly seen slicking out of the exhaust pipe either side of the catalytic converter. This is what the rest of this article is about.

6 cylinder cars – Bonus description!

Just as a side note, on the 6 cylinder engines, there are two pre cat sensors. They are located directly on the exhaust manifolds as they exit the engine block. There is 1 sensor for each bank of 3 cylinders. These banks are either referred to as Bank 1 and Bank 2 or Cyl 1-3 and Cyl 4-6. The sensors are tucked down the side of the engine and need a special tool to remove them. There are plenty of YouTube videos about replacing these sensors though.

Part needed:

You can find cheaper versions for around £45 but I went for the OEM Bosch part number 11781247406 at around £85 off Ebay. You want to be searching for something like “BMW e46 318 pre cat sensor” but then check the description for compatible models and years. If possible, contact the seller to make sure as these are notoriously easy to get the slightly wrong part / connector. I ordered mine from (Ebay name kmspartsonline) and they actually rang me to double check. Top service!

Step 1:

Jack the car up on the front right corner jacking point. The standard BMW jack will do. Go as high as you can then place a secondary support under the car to act as a backup if anything goes wrong. I used a pile of bricks with a small piece of wood on top. You’ll be working under the car, so being super-safe is critical.

Step 2:

bmw_cat_1Locate the sensor. Looking under the car from the left side, it looks like this. Note the jack on the far side of the car. This is BEFORE I added the backup support.

Step 3:


Give the sensor a good spray of WD40 and leave for a few mins. Then just unscrew the sensor. You’ll be doing this from below so think about the direction a little before. With the spanner on the sensor, pull towards the front of the car. In the image from step 2, the unscrew direction is anti-clockwise – as normal. It may take a bit of a tug though as it’s been expanding and shrinking a whole load over time.

Step 4:


Unclip the wire and carefully pull the connector out of it’s retaining clip too. You will probably need two hands to disconnect the connector. I needed a small flat-headed screwdriver to initially prise the connector tabs apart so I could then pull the two halves apart.

Step 5:


Not really a step but here’s the old and new sensor next to each other. Note the grease on the thread of the new sensor. It came like this but if yours didn’t, but a dab of copper grease or similar on the threads before you install.

Step 6:


Screw in the new sensor. I had a bit of a mare locating the thread when trying to do it one handed and from an angle. After some huffing and puffing, I crawled further under the car  and used both hands. Went in straight away. Strange. Tighten it up and reconnect the connector, seating the cable in the clips as you go.

Step 7:

When I started the car, the engine light was still on and the Peake reader reported the same fault. Most modern cars need to be run through 3 full cycles for it to confirm that the fix has cleared the fault. Read more here and here. I’m currently doing this but the initial pickup when accelerating was noticeably stronger, so I’m happy it’s done the job.

Hope that helps!

TEST LINK. £! Nothing to see…

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.