Repairing a faulty cabin blower in an Audi A4 B8

While driving I noticed that the fan in the cabin of the Audi A4 was becomming tempermental. 50% of the time when I would press on the button to demist the front windshield it would fail to start up. I hate having to wipe the glass as it leaves streaks, so I was forced to drive with the windows wound down to get enough air through the cabin to clear the glass. Not the safest of options.

I got the laptop out, connected the VCDS cable and ran the software. I got the following error related to the Heating, ventilation, and air conditioning (HVAC) module in the car.

Address 08: Auto HVAC (J255)       Labels: None
   Part No SW: 8T2 820 043 K    HW: 8T2 820 043 K
   Component: KLIMA 1 ZONE  H05 0120  
   Revision: B0000000    Serial number: 0126.02.080837
   Coding: 34040000
   Shop #: WSC 06325 000 00000
   VCID: 3A6225DBEC5F60D2112454D-806F

2 Faults Found:
01273 - Fresh Air Blower (V2) 
            003 - Mechanical Failure - Intermittent
             Freeze Frame:
                    Fault Status: 00100011
                    Fault Priority: 3
                    Fault Frequency: 55
                    Reset counter: 179
                    Mileage: 264877 km
                    Time Indication: 0
                    Date: 2018.12.29
                    Time: 16:27:51

             Freeze Frame:
                    Temperature: 11.0°C
                    Speed: 0.0 km/h
                    Load: 0.0 %
                    Load: 8.5 %

01273 - Fresh Air Blower (V2) 
            006 - Short to Plus - Intermittent
             Freeze Frame:
                    Fault Status: 00100110
                    Fault Priority: 3
                    Fault Frequency: 14
                    Reset counter: 179
                    Mileage: 264877 km
                    Time Indication: 0
                    Date: 2018.12.29
                    Time: 16:27:53

             Freeze Frame:
                    Temperature: 11.0°C
                    Speed: 0.0 km/h
                    Load: 0.0 %
                    Load: 32.5 %
                    Voltage: 11.60 V

Googling keywords from the issue informed me that the fan/blower motor had to be replaced. New, this part is about 120e off ebay. To do this, I would need the part number to look for. So I would have to take it out to have a look at it.
I roughly followed this guide here to remove the glove compartment. https://www.youtube.com/watch?v=9d3zL-7kJBQ Note, some guides will advise you to remove the Radio to get at some bolts. I did this, but found that there were no bolts that needed removing. So dont do that.
there are about 5 screws to remove from the glove compartment. Two on top, about two on bottom, and one under the panel to the left of the compartment inside the door. Once removed, you will need to disconnect a cable going from the car to the airbag enable/disable switch in the glove compartment. Once this is removed, put the glove compartment aside. You will see the power resistor for the fan and the fan itself. One screw holds the fan. Remove this, and then with two hands, firmly twist the fan housing to remove the whole fan. The blower/fan will look like the following:

I cleaned out the cage for any debris. I spun the fan by hand and found that it was very stiff, only spinning for less than one second before stopping again.

I hooked it up to a 12v power supply limited at 2 amps and found that it turned slowly.

Looking at the part number, it is 8k2 820 021. This is not meant to be a user serviceable part, but as I had nothing to loose, I decided to open it.
I removed the back cover, it is held in place by two screws

I bent back the two copper gates holding spring for the carbon brushes in place. This allowed me to remove the spring and spray some WD40 into them to make sure that they came in and out freely. The brushes had about half their life left. Leave the springs out along with the brushes pulled out.

I then sprayed the bushing closest to the cage too

Next, I decided to have a look at the rear bearing and the commutator. To do this, we have to remove the back piece of metal covering the rear bearing. This is held in place against the main housing by a few crimps in the metal. These can be teased up by a flat screwdriver. Unfortunately, I do not have any photos or video of this.
You will now be able to see the commutator. You can see that there is alot of carbon buildup on the copper, along with wear patterns from the brushes.

This can be cleaned with a bit of sandpaper. I put the cage end into the chuck of an electric drill, held the sandpaper against the commutator, and spun it to smooth and clean it.

Then I used a dental pick to clean between the copper contacts on the commutator for any bits of copper or carbon that might short it.

The rear bushing got spray of wd40 too. I pressed the rear metal housing back into place again. This will require a few goes and some patience. A few taps of a small hammer bent the crimps back into place.

Screw the rear black plastic housing back into place again. I tested it with the power supply again and it appeared to spin with more speed. Manually spinning the cage resulted in it continuing to spin for 2-3 seconds before coming to a stop. Not great, but definitely better than before.

I installed it back into the car. VCDS along with the cable was used to reset the all errors on the car. After a month of use, the fan works now as expected, and there are no errors showing up on VCDS. Success! 

Repairing Audi A4 B8 8K door not unlocking with remote fob

When you buy a pretty premium saloon, you would expect reliability. However, I have found that the german engineering of the Audi a bit underwhelming in terms of both reliability and ease of repair. Too often, small little niggley things have given up the ghost on the A4. The latest to go was locking mechanism on the drivers side door. When I tried to unlock the door with the remote key fob, the door made made a grumble but failed to unlock. It would require a second press of the fob to unlock the door, or else it wouldnt open at all. Instead, I would have to roll down the windows with the fob and open the door by reaching in and opening it from the inside.
I also noticed that the automatic locking of the door when the vehicle went over 30kph was making a strange noise on the drivers side.

I tried a few different solutions outlined on the various forums:

• Pull the outside and inside handle at the same time until you feel it click: This appeared to work for a while, but failed again. 
• Spray WD40 over all the moving parts including lock tumbler and handle cable: No effect
• Dismantle door lock module and grease all parts: no effect

Using the VAG-COM VCDS diagnosis software and cable, I found a that the door lock module was throwing a "outside limit" error. Worse again, after a while, the issue appeared in the passengers side door too. Due to the noise that the locking mechanism made, I suspected the door motor. As such, I removed the trim and then the paneling of the door. There are about 6 torx screws that you have to remove to unfasten the paneling. Then you have to start pulling out the panel from the bottom. once you get the top, you can lift it upwards to remove it. Next, you can remove the blue internal door handle cable by unhooking it from the door handle side. Once that is done, you have to remove the outside door handle cable from the lock module. Reach into the door frame and twist the yellow catch on the end of the cable going into the door lock module. Next, remove a rubber gromit on the edge of the door frame to expose a grub screw securing the lock tumbler. Loosen this, and pull out the lock tumbler from the outside. Then to remove the door lock module, you will have to remove two large bolts from the outside edge of the door frame. Then you can reach in and remove the loosened door lock module.

Take the module to your work bench and remove all the screws on the outside. Open up the small gray hatch window. You will see two axels coming out from the main housing into the locking mechanism. Insert a flat screwdriver and prise the axels from the lock mechanism. You will be left with just the main housing. Using a spludger tool, prise the two half of the housing apart. Inspect the two halves when apart- if the water proof gromit has come loose, press it back into place.

Inside, you will see the two motors of the module. Remove the largest. Clean the two contact that insert into the motor. I used some fine (2000 grit) sandpaper. At this stage, I tested the motor using a 12v supply and found that it struggled to turn without help. There was obviously something wrong with it. Using a small screwdriver, lift the two tabs on the end of the motor. You can then prise the end off the motor. There was much carbon dust in the motor from the brushes. As such, I tapped the motor on the desk to knock it out. The commutator on the motor was blackened from the brushes. Again, with the fine grit sandpaper, this was quickly cleaned up. You can remove the brushes with a sim card removal tool. I cleaned these up with a small rag. I put the motor back together and tested it with a 12v supply. It ran perfectly.

Finally, you can put everything back again. Using the VAG-COM VCDS diagnosis software and cable, I reset the error codes. I tested the door, and it worked perfectly!. A month later and it still hasnt given any problems or caused errors in VCDS.

Note: I had a second door stop unlocking that the guide above did not repair. Instead, I had to replace the "bowden cable" to fix this. You can see it in the photos below with the sky blue rubber around it. It appears That these do not move smoothly enough after a few years to allow the lock to reset back to its previous position.

Building a RaspberryPi Time Capsule: The cheap, fast and simple guide

I am a longtime fan of Apples "Timemachine" data backup software. Having used multiple flavours of backup software on Linux and Windows, Timemachine has been by far the simplest and easiest one to use. In its simplest form, you only need to plug in a bog-standard hard drive into your Macbook to save your backups. But what if you couldn't even be bothered plugging in a USB drive? Is there a way to do it wirelessly? Good news! Apple sell a wireless backup solution, the "Time Capsule". The bad news? Its $350. There is, however, a cheaper solution.

Since the Raspberry Pi hobbyist development board came out, there have been many guides written on how to convert it into an Apple Timemachine compatible device. Although they work, I have found them to be overly complicated for what has to be done. Also, they require that the Raspberry Pi has a static IP, something that is inconvenient if you want to set up your backup on a new network when you move house, for example. Thankfully, I found one guide that offered a simpler solution. This guide removed much of the un-needed steps from the previous guides. This guide does require that you do the first preliminary backup over the network. For me, with over 300Gb of data to backup, this would have taken over 24 hours to transfer. It is much faster to do the preliminary backup over USB. As such, I have merged the two guides above into one, cheap, fast and simple Raspberry Pi - Time Capsule guide. 

Parts list

Required 

1. SD card
2. Raspberry Pi
3. 3.5mm Portable Harddrive 

Optional 

1. USB Wifi dongle 
2. Philips screwdriver
3. Sharp blade
4. Mini USB cable 
5. Soldering iron and solder

Setting up the Hard drive 

1. Plug your USB into your Macbook. 
2. Click on Applications - System Preferences - Time Machine. 
3. Tell Time Machine which drive to use for backups by clicking the “Select Backup Disk…” button, selecting your newly plugged in drive, then clicking the “Use for Backup” button. 
4. Time Machine will schedule your first backup to start in just two minutes. You will have to wait a while, as this can take a few hours. 
5. Unplug the hard drive when done. 

Setting up and configuring the Raspberry Pi 

1. Download the latest "Raspbian" OS image file for the Raspberry Pi. Dont download the "NOOB" version, as this will require that you use a TV to set it up. We will be using SSH in this guide. 
2. Burn the OS image to the Raspberry Pi. If you are using OSX, use "RPi Easy SD card setup" app. This will take about 20min. Dont worry if you get an error saying "Could not eject card" at the end. It should have completed successfully. 
3. Put the SD card in the Raspberry Pi. Connect an ethernet cable from the Raspberry Pi to your router. Power up the Raspberry Pi. 
4. Log into your router on your internet browser and get the IP address of the Raspberry Pi. You can also get this using a TV connected to the Raspberry Pi. 
5. Open a terminal in OSX, and ssh into the raspberry Pi. The password is "raspberry"

   $ssh pi@THEIPADDRESS 

6. Update software on the device

   $sudo apt-get update 

   $sudo apt-get upgrade 

7. Install the software that we will need. Netatalk is used for creating NFS shares, the others are used for reading the HFS formatted USB drive

   $sudo apt-get install netatalk 

   $sudo apt-get install hfsplus hfsutils hfsprogs 

8. Edit the fstab file to automatically mount the usb drive on boot up

   $sudo nano /etc/fstab 

9. Add the following lines, then ctrl + c to save and exit. Note: "sda2" was the partition on my USB drive that needed to be mounted. Yours may be sda1. Run "dmesg" to see which one you will have to mount. 

   /dev/sda2 /mnt/TimeMachine hfsplus rw,force,exec,auto,users 0 3

10. Open up the permissions of the mount directory

    $sudo chmod 777 /mnt/TimeMachine

11. Attempt to mount the usb drive:

    $sudo mount /dev/sda1 

    If it mounted successfully, try and write to the USB drive using "mkdir /mnt/Timemachine/testDir". Note: if you reboot the Raspberry Pi and the line in the fstab is not correct, the raspberry Pi will not boot up properly again. The easiest way to recover will be to write a new raspbian image to it. Also use the mount command to check that /dev/sda2 is mapped to /mnt/TimeMachine. Make sure that the letters rw are in the same result. This ensures that we have read/write access to the partition.
12. Add the directory to the "Pi" user (the user that you will be logging in from your macbook with)

    $sudo chown -R pi /mnt/TimeMachine 

13. Edit the Netatalk config file to share the Timemachine directory

    $sudo nano /etc/netatalk/AppleVolumes.default 

    Add the following line to the end, save and exit.

    /mnt/TimeMachine "Time Machine" options:tm 

14. Restart netatalk

    $sudo service netatalk restart 

15. Back on your macbook, a share called "raspberrypi" should appear on the left side of your finder window. If not, in finder, click on Go - Connect to server and type "afp://raspberrypi" or "afp://IPADDRESSOFRASPBERRYPI" into the address window. After you press enter, the shared directory should appear.
16. Go into Timemachine again. Remove the previous backup disk. Click on "select disk" and select the raspberry Pi. It will prompt your for a username and password. Use "pi" for the username and "raspberry" for the password.
17. Thats it! The macbook should recognise the previous backup and continue from there. After the previous backup over USB, the second backup over wireless should be alot faster.

Enabling wireless on the RaspberryPi Time Capsule (optional)

You can remove the requirement of having an ethernet cable between the router and the Raspberry Pi by plugging in a small usb wifi dongle into the Raspberry Pi and configuring the wireless. I used a Ralink RT5370 from ebay for this. To connect your Raspberry Pi to the wireless network, here are the steps.

1. SSH into the Raspberry Pi over ethernet (see above). 
2. Install the WPA wireless tools

   sudo apt-get install wpasupplicant wireless-tools 

3. Edit the networking file to use the wpa-supplicant file for wireless configuration

   sudo nano /etc/network/interfaces

   Ensure the wlan0 section uses the following lines:

   allow-hotplug wlan0
   iface wlan0 inet manual
   wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
   iface default inet dhcp
   

4. Edit the wpa-supplicant file

   sudo nano /etc/wpa_supplicant/wpa_supplicant.conf

   Ensure that it has the following lines

   ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
   update_config=1
   
   network={
           ssid="YourSSID"
           psk="password"
           key_mgmt=WPA-PSK
   }
   
   

5. Save the file, disconnect the ethernet cable, and reboot the Raspberry Pi. It should now connect to the wireless network.

Powering the Raspberry Pi off the hard drive (optional)

I did not want to have to have a separate power supply for the hard drive and the Raspberry Pi as both would be kept together at all times. As such, I looked into powering the Raspberry Pi off the supply of the hard drive. 

1. Using a sharp knife, cut the male, full size usb connector off your mini usb cable, exposing the four wires. 
2. Tape up the two data lines, we wont need them and we dont want them touching anything. They are normally the green and white wires. 
3. Expose around 2mm of the conductor from the 5v (red) and ground (black) wires. Tin them with solder and the soldering iron. 
4. Dismantle your portable hard drive. Each one will be different. For mine, I had to remove 4 screws from the underside, and slide out the harddrive and controller from one end.  
5. Look for the four wires going from the controller to the hard drive. There should be two black, one yellow and one red. We are looking for the 5v wire (red) and either of the ground wires (black). Solder the red and black wires from the USB cable to the points on the controller board that the corresponding hard drive wires are soldered to. 
6. Find a way to route the cable out of the portable hard drive caddy. I drilled a small hole with the screwdriver and pulled the usb cable through it. I also tied a knot in the cable on the end inside the caddy so that it would not get pulled out through the hole if it was tugged on. 
7. Put everything back together, power up the portable hard drive, and plug in the Raspberry Pi. The raspberry Pi should power up successfully. 

Coding Python (Pydev) on Ubuntu 12.04 with Eclipse Juno

A short blog post. After having installed the latest pydev on the newest eclipse juno, I found that python would not work. All the relevant buttons for python development did not appear, even though the software manager reported that pydev was installed. As such, to get both working correctly I had to do the following:

1. Following this guide, http://www.vogella.com/articles/Python/article.htmlH as far as installing pydev. However, do not go any further as installing pydev 3.0 didnt seem to work. Niether did it work on Eclipse kepler 4.0.3. A similiar issue was reported here: http://stackoverflow.com/questions/19916925/problems-downloading-artifact-error-reading-signed-content
2. As such, when eclipse is installed, go to help-> install new software. For the source, type: “http://pydev.org/updates”. 
3. Uncheck “show only the latest versions of available software”. 
4. Select Pydev for Eclipse version 2.8.2.
5. Works!

Correcting incorrect time-offset on an Ubuntu server

Here is a quick post on a solution to an issue that affected my Ubuntu server. I noticed that me cron jobs were getting executed about a hour or two later than they were set to run at. Logging into the server and running the command "date" confirmed what I easily suspected: that the clock was off by 1h 45min.

Running the command:

$sudo ntpdate

to update the clock returned the error

ntpdate - no servers can be used, exiting.

So then I ran the command

$sudo ntpdate 0.uk.pool.ntp.org"

which returned the following:

28 Apr 14:28:40 ntpdate[23357]: step time server 109.123.121.128 offset 2311.837165 sec.

Great, I thought, problem solved. Unfortunately not. When I ran the command "date" again, the server was still off by an hour:

$date
Mon Apr 28 14:33:45 UTC 2014.

It was actually 15.33. Suspecting an issue with Daylight Savings Time (DST) was the issue, or to be more specific, that the server wasnt using it, I looked to enable it. A quick Google informed me that an Ubuntu installation gets its DST settings from knowledge of its physical location, and the time server that it is conencted to. I had already configured it to use a suitable time server with the command "$ sudo ntpdate 0.uk.pool.ntp.org", so I had to reconfigure its location from the terminal. To do this, run the following command:

$sudo dpkg-reconfigure tzdata

You will be presented with a terminal GUI. Select your locality. Then when completed, you will be greeted by the updated time: 

Current default time zone: 'Europe/Dublin'

Local time is now:      Mon Apr 28 15:33:45 IST 2014.
Universal Time is now:  Mon Apr 28 14:33:45 UTC 2014.

Running "date" now confirms the corrected time:

$date
Mon Apr 28 15:33:56 IST 2014

Problem solved! 

Repairing intermittent wifi/wireless on a 15" Macbook Pro 2011

From reading a couple of articles on this site, you may have noticed that although I may be critical of some Apple goods, in general, I am a fan. However, there are some times that I am extremely fustrated when their hardware breaks, such as when my MacBook Pro 15" wifi decided to start acting abnormally. For reference, it have a Macbook Pro 15" Unibody Early 2011 (Released February 2011 2.2 GHz Quad-core Intel Core i7 Processor, thunderbolt, Broadcom BCM94331PCIEBT4AX wifi/bluetooth card)




The issue
After a while of use, the wireless internet dies. The signal strength indicator fan in the top right corner still indicates five full bars. Right Clicking on the icon and clicking on "Turn wi-fi off" makes the fan icon go blank as it should, but the previously connected to network remains in the list check marked, which it shouldnt. All other wifi networks in the area disappear from the list. The status at the top of the drop down box says "Wi-Fi: looking for networks".
Right clicking on the icon and clicking on "Turn wifi-off" makes the icon go blank, as it should. Right-clicking on the icon and clicking on "Turn Wifi-On" does not enable the wifi. The fan icon stays blank, which it shouldn't. The previously "connected to" network remains check marked, but there is no connection to the internet.
Putting the laptop to sleep with the lid and waking it again results in five faded bars, but now no wifi networks can be found, and there is no connection to the internet. The issue occurred round once a day at the beginning. By saving my work and rebooting the laptop, the issue has been manageable. However, it became unmanageable when it occurred more and more often to the point where I had to save my work reboot my laptop every 1-2 hours of use.

What I tried to do to repair the issue

1. Reboot the laptop. A temporary solution is to reboot the laptop, in which the wifi performs as it should until the issue occurs again.
2. Use a USB dongle. A semi permanent solution was for me to buy a Ralink usb wifi adapter, that worked fine but was not ideal. It felt a bit ridiculous and cumbersome to have to use a $10 usb adapter to repair a Macbook Pro that cost $2000.
3. Connect to a different wifi network. This did not work. The issue occurs when connected to other wifi networks, such as my parents one at home. This hinted that it was not a wireless router issue.
4. Reset PRAM, NRAM, etc. This was only a temporary solution, as was just simply rebooting the laptop.
5. Deleting my Airport settings files. Again, this was only a temporary solution, bus so was simply rebooting.
6. Wiped the harddrive and installed Mountain Lion. The issue remained, even with a clean installation with no restoration of my old settings from TimeMachine. The issue was the same when I installed Lion, and Mavericks. I even noticed the same issue once with the wifi when I booted off just the OSX installation disk. As such, I believed that the the issue is hardware related.
7. Visual inspection of the hardware. I took off the bottom cover of the laptop to see if there are any visually obvious loose connections, but there are none.
8. Took the laptop to an authorised Apple Repair Center. They did nothing. As it was an intermittent issue, they said that the wifi was working fine when they ran their DVD of hardware tests. As far as I know, they don't do any long-term tests, even though I had requested them to do so. They blamed the wireless router (which I knew was not an issue, see above) and mu wifi settings (which I also knew was not an issue, see above).
9. Replaced the wifi card. This did not work. I bought a new Broadcom BCM94331PCIEBT4AX for around $35 off eBay. Following a guide on ifixit, http://www.ifixit.com/Guide/MacBook+Pro+15-Inch+Unibody+Early+2011+AirPort-Bluet ooth+Cable+Replacement/5887 I replaced the card easily enough. It was just around 10 screws in total, easily manageable in an hour if you take your time. Unfortunately, the issue returned again after a few hours of use. 
10. Replaced the motherboard, and the screen. I assume means that the wifi antennas got replaced. This did not work. On an unrelated issue with the graphics card, Apple agreed to replace the motherboard, LVDS, and LCD screen out of warranty (really good of them). Unfortunately, their authorised repair center took nearly 6 months to do the repair (again, they were a bad representation of Apple). Unfortunately, the wifi issue returned once again after a few hours of work.

What repaired it in the end
Finally, in a last ditch attempt, and as it seemed to be the only part in the laptop not replaced (including software), I bought a replacement wifi/bluetooth cable off ebay for around $30. This worked! It has been going strong now for nearly three weeks with no drop in wifi. It was pretty expensive for a simple black ribbon cable but I am glad that it worked. There was no visual damage to the old cable, but I suspect myself that the bottom cover may have pinched the cable against some edge near the motherboard, thus causing the intermittent drop-off in wifi.

Update 20/01/2013 : I have re-opened the laptop to inspect the location of the ribbon cable (Figure 1). In (Figure 2) you can see the point on the rear of bottom cover (2) that places pressure on the end of the ribbon cable. You can see that there is a visible imprint on the plastic foil covering the back of where they are in contact. Due to the level of imprint and its location, I suspect that this causes excess pressure on the cable connector when the laptop receives knocks from the underside.

Figure 1: The faulty macbook wifi cable is shown in (1). The point on the back cover that I suspect may have been putting too much pressure on the ribbon cable is located at (2)

Figure 2: The point on the rear of bottom cover (2) that places pressure on the end of the ribbon cable. You can see that there is a visible imprint on the plastic foil covering the back of where they are in contact. Due to the level of imprint and its location, I suspect that this causes excess pressure on the cable connector when the laptop receives knocks from the underside.