Replacing the Electric Door Lock Actuator on a BMW E36

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The BMW 3-series cars manufactured from 1991-1999 are getting to the age where the electric door actuators are wearing out and there’s nothing more frustrating than a door lock that won’t respond to the key fob. My wife’s BMW 328i passenger door had this problem a few years ago and I recalled replacing one of the actuators with instructions I found on the Internet. However, when her driver’s side door began having the same issue, the instructions that I found on the Internet seemed to be lacking in the important details, and it had been long enough that I had to ‘re-learn’ the tricks I had forgotten since I last tackled this project. So I decided to write up this article to help anyone who is contemplating this as a DIY project.

You will need the following tools: Torx driver with T-20 and T-27 bits, non marring pry bars and (possibly) a set of vice grips.

Useful Tools, non marring pry bars and a Torx set (only need T-20 and T27 bits).

Useful Tools, non marring pry bars and a Torx set (only need T-20 and T27 bits).

BMW door actuators are available from several on-line retailers. The best price I’ve found for OEM actuators was at BMW Parts Web. Just search on p/n 67-11-1-387-726 (front actuator) or p/n 67-11-8-353-011 (rear actuator) for E36 models. Just be sure to get the correct one since the front doors use a different connector that has 6 pins whereas the rear actuators have only 3 pins. The ones I got were aftermarket units that I can’t find anymore.

Original (left) and replacement (right) door lock actuators.

Original (left) and replacement (right) door lock actuators.

The door panels on the E36 are not hard to remove, you just need to pop off two screw covers behind the inside handle, and remove the screws they covered with T20 torx driver. Each screw was a different length, which I didn’t notice until I was going to re-install them. The longer screw goes in the hole toward the front of the handle.

These covers expose two screws you must remove.

Then you have to remove the dish behind the door pull and this is where I ran into trouble. Evidently, a lot of people break this part, assuming that it comes straight out. The advice is to push it forward. However, until you pry up the front of it, there’s no way it will move forward, so that is the step everyone seemed to leave off. First pry up the front, and THEN push forward.

Push forward, but only after prying up the front part.

See how latches need to be pushed forward to release.

Next you remove the door lock plunger by unscrewing it (counter clockwise), and you may need some pliers to gently grab it and get it started because it’s hard to grasp by hand and apply any torque.

Door lock plunger

Door lock plunger

The next step is to pry off the door panel using a non-marring pry tool and gently pop out all of the plastic fasteners as you work your way around the door. You’ll need to rotate it up to get it off of the door lock plunger push rod.

Prying BMW Door Panel away from door

Prying BMW Door Panel away from door

When the door panel comes off, it will still be connected by the wires connected to two speakers and to the buttons that are used to adjust the mirror (if it’s the driver side door). The connectors are held in with friction, so you don’t have to find any hidden latches to free them, just pull them out. They are keyed so you can’t install them backwards.

Disconnecting BMW door cables

After the door panel is free, you’ll need to peel back a foam sound insulator that is held in place by some very sticky black adhesive. It’s best to peel it half way off and then use some duct tape to hold it out of the way. Be careful around the black adhesive, since it will get over all over you if you touch it.

Internal Door insulation

Internal Door Foam Insulation

Peel back foam insulation about half way and hold in place with duct tape.

Next you need to loosen 3 screws that hold in the door lock mechanism with a T27 torx driver. However, these screws have thread locking compound on them and I soon realized that I was either going to destroy the Torx recess or break the driver bit unless I loosened them with vice grips first. Fortunately this is easy to do. Use adhesive tape over the adjacent paint around the screw heads if you want to avoid scratching it with the vice grips.

Using vice grips to loosen screws

These screws were in so tight they need help to get them started.

There is a rod that goes to the door opening latch and the latch can be removed with a T20 driver. I don’t have a picture of this, but it’s pretty self-evident how to take it off and disconnect the rod. Mine had a Tinnerman type nut that fell off the back, so be careful to catch the nut as you loosen the screw. Removing the latch allows you to move the locking mechanism with a bit more freedom.

Once you’ve done this, the mechanism can be wiggled about inside, but there’s not enough room to get it out of the door. Cut off any tie wraps on the wires going to the actuator to gain a bit more wiggle room. This is where the confusion ensued. All you really need to get out is the electric actuator, but it wasn’t obvious how it was held on and whether I’d be able to install the new one working in the blind, so to speak. I even got desperate enough that I removed what I thought was a simple stiffening bracket that was in the way that turned out to be the curved window track. In retrospect, it didn’t give me much more freedom to move the lock mechanism about and I worried that it would be hard to reinstall, since its upper end mated with another part that was up inside a blind recess. If I were to do it again, I’d try to avoid removing the window track.

The electric actuator is held in place by a cantilevered plastic latch that grabs a recessed depression on its housing. You need to feel around for this latch, pull it back and lift the actuator up and away from the door latch mechanism. Once you do this, you can bring the electric actuator out into the open so you can disconnect the connector.

This latch holds actuator in place.

Latch recess on door actuator

Latch recess on door actuator

The connector is one of those unique to BMW where you push a mechanism down and it forces the connector outward over some pins that follow a curved track in a cam mechanism.

Removing the cable from the actuator

Push cable lock this way to unlatch it.

Removing cable from BMW door actuator

Removing cable from BMW door actuator

The re-installation of the new actuator on to the cable is just the reverse. You have to push the latch mechanism all the way down, and then align the cam pins in their slots in the connector and then pull the mechanism up to draw the connector into its recess.

Once you’ve got the new actuator in place on the cable, the challenge is to get it back on the door latch mechanism by a sense of feel. There are 4 flat metal pins that need to mate up with holes in the actuator. Three of these are in line with each other and they have specific holes they need to mate with on the actuator. The two end ones go up into rectangular alignment holes and the middle one goes into the part of the actuator that moves back and forth. Make sure the middle hole is aligned with actuator pin by either pushing it forward or backward. When installed on the cable, this action will either open or close the door locks as you do it if you’re working on one of the front doors since they control the behavior of all other locks in the system.

Note holes for accepting stamped metal pins in door lock mechanism.

Note holes for accepting stamped metal pins in door lock mechanism.

In order to get the door lock actuator to align laterally, you will have to apply some sideways force since the cantilevered plastic latch will be pushing against it and you need to spring it outward a bit. Once the metal stampings are aligned in their respective holes, you can push the actuator down on the latch mechanism until the latch snaps in place. This was the hardest part of the whole project. I assumed I was going to be able to get the door latch mechanism out in the open or at least in a place that was easier to see, but it ended up being more of an exercise in working in a confined space with very limited visibility and access.

After I got everything back in place, there was a panicky moment where I had somehow gotten the door latch mechanism into a locked state even though the door was still open. Then door would not close. There was just a loud thud as the hook and latch banged into each other when I attempted to close the door. I was thinking I might have to re-open everything again, but I started playing with the lock, the key, and manually trying to open the lock by hand and I eventually got it all back in the proper state so the door would close normally.

It was with a great sigh of relief when everything was back together. These parts generally fail over time, and my wife had been experiencing problems for months where it was intermittent. Finally, the cold weather made it happen nearly 100% of the time, so she was very grateful to have a working set of locks again.

The BMW electric door actuators are available on-line from suppliers like Bavarian Auto for around $90 each + shipping but the best price was from BMW Parts Web and that was true of most BMW parts I’ve checked on.

Five Essential Skills for Modern Web Design

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5 pillars of web designI teach computer related courses at Aims Community College, including introductory and advanced courses in web design and programming. I also do consulting in web applications, which usually involves PHP programming, e-commerce, and Content Management Systems (CMS) like Magento, ZenCart and WordPress. Periodically, people ask me what they need to know to be a web designer these days. Some of them may have had a passing familiarity with HTML from some web pages they created a decade ago, but web design has changed a lot since then and they want to wrap their minds around what it requires today to work in web technology. To be an effective web designer today, it is necessary to master what I call the 5 pillars of modern web design.

1. HTML5

When the world wide web was introduced back in the early 1990s, it was based on HyperText Markup Language (HTML), and it was simple. I recall back then you could learn web design by using the ‘show source’ feature of the browser to see how a page was constructed. Everything you needed to know was right there in a single page. HTML is the first pillar of web design, you must understand HTML to do anything with web pages, preferably the latest version which is HTML5. However, if HTML is all you know, the pages you create will look like they’re straight out of the 1990s.

2. CSS

Shortly after HTML was invented, a styling language known as CSS (Cascading Styling Sheets) was developed which took the appearance of the page and separated it from the content. Although having a separate styling language complicated things, it was for the best because you could change the way a page appeared simply by changing a few values in the CSS. However, unlike HTML, CSS isn’t so easy to learn by inspection. In fact, there are things about the way CSS works that can make it exasperating to learn. I consider CSS to be the second pillar of web design.

3. JavaScript

The third pillar of web design was introduced with client side scripting when Netscape invented LiveScript. A scripting language that runs inside the browser allows you to add dynamic effects to web pages, along with a useful functionality like checking forms are filled out properly before submitting them. LiveScript didn’t take off at first, but in an agreement with Sun, Netscape changed its name to JavaScript, and thanks to significant hype surrounding the Java language at the time, it began to gain traction. Today, JavaScript is the only language that works inside all browsers without needing a plugin thus making it a standard, and with the many JavaScript libraries that have been introduced, browsers are now able to render pages that have the look and feel of applications as opposed to static documents.

4. Server Side Scripting

The fourth pillar of web design is server side scripting. Over the years, many languages have been used for server side scripting, such as Perl, PHP, Ruby, Python, and ASP. These languages are intermingled with HTML and JavaScript but they are executed on the server side, thus rendering pages that have dynamic content. Consider the construction of an HTML table that forms a shopping cart. The server needs to keep track of the cart’s contents and generate the HTML to build the table on the fly when the user selects a button to show cart contents. These days, just about all the elements of a page can be rendered dynamically from a database using a scripting language, including much of the content on a page. In fact, the page you’re reading right now and all the associated content around it is stored in a database. That’s the way WordPress, the content management system that is displaying this page, works its magic. To edit the page, it’s a simple matter of working through some web forms, instead of hand coding the HTML/CSS and JavaScript you’d find if you looked at this page’s source code.

5. Database

The fifth pillar of web design is the database. Just about all advanced websites today have migrated to some form of a database-backed content management system (CMS). There are many CMSs to choose from, but what they all have in common is that they rely on dynamic calls to the database to get the data they need to render the pages. This means the web designer needs to understand how to interact with databases and have a good understanding of SQL (Structured Query Language).

Even if you master these five essential skills, you’ll need a few more skills to put together attractive websites. For example, you still need to know about graphics design and how to edit images so that they look good and load fast on a web page. Knowing about typography, color schemes, and other artistic concerns are also very important so that your website doesn’t scare people away and for graphics skills, you may need to rely on an expert in that field since it’s a rare person who can write code and produce beautiful artwork.

Now I know there are some who might argue that with modern Content Management Systems such as WordPress, much of the work is done for you and you can be a web designer without having to know anything about databases, scripting languages, CSS or HTML. That may be the case for simple websites, but if you don’t know the basics, you’ll eventually run into problems you won’t be able to fix. A client might ask for a simple modification to a theme or some file buried inside the CMS and if you don’t have the 5 essential skills mentioned here, you won’t be able to do it.

Cleaning Your Laptop’s Heatsink to Solve Overheating Issues

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In the past few months I’ve run into a number of people who have experienced problems with their laptops running hot. I had an HP/Compaq nx6110 laptop sitting in a drawer that I recalled had been exhibiting the same issue. I wanted to loan it to my nephew to use during a visit and I thought I’d take the opportunity to put in a new battery and check to see the if I could find the root cause of the overheating issue.

I had checked a number of sites on the web that talked about overheating issues with laptops, but none of them talked about the potential for the fan/heatsink assembly to collect dust and block the airflow through the heatsink. If you think about it, most laptops operate like a vacuum cleaner in that they suck air up through a hole in the bottom of the case and blow it out the side. The air must flow through a radiator with fins that can collect lint, dust, pet hair and anything else that it might find in ample quantities when the laptop is placed on a carpet, blanket, or your lap. So the odds are pretty good that if you’ve had your laptop for any length of time, dust has accumulated inside and has negatively affected the heatsink’s ability to remove heat from the CPU.

In preparation for removing the fan from the laptop, I downloaded a PDF of HP nx6110 service manual from the HP website. You can do a Google search for your laptop’s model and the words, ‘service manual’ to see if the manufacturer makes the service manual available online. You may notice that removing the fan seems to require all kinds of parts to be taken off the laptop since they seem to cover everything else first, but in my case, it only involved removing the keyboard, which turned out to be quite easy.

The steps were:

1. Remove battery and the cover for the memory (1 Phillips screw).
2. Remove 2 T8 Torx screws exposed after the memory cover is removed. These screws hold in the keyboard.
3. Slide four latches on the keyboard downward to release the keyboard.
4. Remove the fan (2 Phillips screws).

Although I removed the fan and keyboard cables, I found out later that I really didn’t need to do this to get at the heatsink, you can simply lay them over as long as you’re careful not to move them and put strain on the cables.

I’ve attached some images of the fan and heatsink below. Click on any image for a higher resolution version of it.

HP nx6110 fan

Removal of the keyboard exposes the fan/heatsink

As you can see from the picture above, the fan is exposed once the keyboard is removed. It doesn’t appear to be too dirty, but the dust is hidden between the fan and the heatsink.

HP nx61110 heatsink

Heasink with dust

Now that the fan has been removed, you can see that there is a lot of dust that has accumulated on the heatsink. You can use a brush to remove the dust and then blow it out with compressed air.

HP nx6110 heatsink

Heatsink after cleaning

The dust that had accumulated on the heatsink caused the air to be blocked and so the air that does get through is very hot since a smaller portion of the heatsink is being used to remove the heat. It can also increase the velocity of the air because it’s forced through a smaller restriction. Eventually, however, if it’s not cleaned, the heatsink will no longer be able to do its job at all and the computer could shut down due to overheating.

Once the heatsink was cleaned, the air that exited the vent was much cooler, and the fan didn’t need to work as hard to keep the CPU cool (around 45 °C). In doing some research, I found that the BIOS was using various CPU temperature thresholds to determine when to turn the fan on and when to increase its speed. In my case, the BIOS was original and it was turning the fan on at 40 °C, and so I decided to see if any improvements were possible by updating the BIOS. Sure enough, a newer BIOS available from HP’s website had raised this limit to 45 °C which turned out to be much better, since that is the temperature where the CPU tends to stabilize when it’s at idle and so the fan stays off unless you’re doing something that causes the CPU to become busy.

I have a friend with an HP laptop dv6 model and it had an overheating problem that was so severe that it would reach 90 °C and shut itself down whenever she used it for more than 15 minutes. After searching through forums for many weeks she finally came across a thread that suggested updating the video driver and the BIOS to fix an overheating issue. That turned out to be the fix in her case. Now her computer runs very cool. So make sure you’re running all the latest updates from the manufacturer.

If you clean your heatsink and your overheating problems persist, you may want to check and see if there are any processes that are keeping the CPU busy all the time. Any time the CPU utilization goes up, the fan will come on at a higher speed. You can use Windows built-in Task Manager to do monitor CPU utilization by pressing CTL-ALT-DEL keys simultaneously. A better solution than Task Manager for examining CPU utilization is the Process Explorer which is free for downloading from Microsoft. I also downloaded a free utility to monitor the CPU temperature called Core Temp. I found that I had multiple virus scanners running (you only need one of these) and some other processes I didn’t need, so I removed the software responsible for running these processes.

I found that although Core Temp was helpful, it sometimes interfered with the BIOS in reading the temperature of the CPU. A better program for measuring CPU temperature on this model of laptop was Speedfan.

can of compressed air
If taking your computer apart sounds frightening to you, or if you have a laptop where absolutely everything must be removed to get to the heatsink, then another option is to use a can of compressed air that you can buy at any office store and blow air backward through the fan’s vent. Feel for which direction the fan blows and determine where it’s exhausting the warm air. Then shut down the computer and aim the straw into the exhaust vents and if you see dust coming out through the intake vents, then you’re making progress. When dust collects on the heatsink, it continues to attract more dust like a log jam in a river. Blowing the air backward through the vent can clear this log jam.

How to schedule a recurring backup of a Windows XP folder to a Network share drive

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I have worked on computer backup products for more than 20 years and I still find most of them to be complicated to set up and use. They sometimes include so many features and options that people just give up in despair while trying to configure them.

If you have a network share drive and want to make periodic backups to it, you can do it without purchasing any new software and without having to resort to using Microsoft’s built-in backup utility which stores backups in a proprietary file format. This approach requires a special restore program to examine them or to copy them back to your PC. The fact that Microsoft’s backup utility is so well hidden speaks volumes for their confidence in customers being able to successfully find and use it.

If all you want to do is schedule a simple automated backup of a folder, I will explain an easy 3-step process to set up a recurring backup on Windows XP. I haven’t investigated an equivalent procedure for Windows Vista or Win7, but I assume this technique would work there as well since those operating systems also have similar built-in capabilities.

Step 1: Map the network share to a drive letter.

The first step is to set up the network drive as a drive letter on your PC. To do that, just open up Windows Explorer, basically any folder, and under the Tools menu, select “Map Network Drive”. Your network drive will likely have a name such as “server” and a share that you wish to use such as “backup”. In the dialog box that pops up, you can just type in \\server\backup. XP will let you use the ‘Browse’ feature to find your network drive and share if you don’t happen to know them by name. Once located, you can assign it an available drive letter. Make sure to check the box for your PC to reconnect to it at logon.

Step 2: Create a simple xcopy command in a batch file.

Let’s say the first step gave your network drive the letter X:.

We will now create a simple batch file called backup.bat in Notepad with the following single line that looks like this example:

xcopy "c:\Documents and Settings\Lee\My Documents\SWfiles\*.*" x:\Backup\SWfiles /d /e /y

(that should all be on a single line, but it got wrapped here)

This is the DOS xcopy command which is built into XP. It works like this:

xcopy "source files" "destination folder" /options.

I’ve selected the source files as “c:\Documents and Settings\Lee\My Documents\SWfiles\*.*”. That will back up every file and folder under the folder called SWfiles. I had to put quotes around it because some of the folder names have spaces in them. If you have spaces in any of the folder names, you will need these quotes around the source and/or destination name.

The purpose of the options is as follows:

/d – This option only backs up the file if the source file is newer than the destination file that may already exist. This allows the backup to avoid unnecessary writing if the file hasn’t changed since the last backup.

/e – This option makes the xcopy command search in sub-folders so you back those up files too.

/y – This is to avoid having the job ask for your permission to overwrite existing files.

Let’s save this file as backup.bat in any convenient folder. I put mine in My Documents.

Test it by double clicking on it to confirm it backs up the folder to your network share.

Step 3: Set up a scheduled task to run the batch file.

To open Scheduled Tasks, click Start, click All Programs, point to Accessories, point to System Tools, and then click Scheduled Tasks.

Double-click Add Scheduled Task to start the Scheduled Task Wizard, and then click Next in the first dialog box. Just follow the wizard to select the backup.bat file and don’t worry if you can’t find the proper options to select, the task is very easy to edit once it’s finished. Unless you select, ‘run only when logged on’, you will have to select a user/password to run this task so if you don’t already have a password set for yourself, you will need to set one up. I set up a My Documents backup to run once a day, but for my SWfiles folder, I wanted it to back it up once an hour. If at first you don’t get it right, you can edit the task by double-clicking on it. Then you can select ‘Advanced’ options to set it up to run it every hour. Set the duration to 24 hours so it will run every hour of the day.

Here’s an example of what the Scheduled Tasks screen looks like:

The Task Scheduler for Windows XP

The Task Scheduler for Windows XP, Click for larger image.

Please keep in mind that if you do this on a laptop, the backups will only happen when you’re connected to your network, so if you’re off traveling with your laptop, make sure you use another backup method (perhaps a Picture Keeper customized to backup all of your favorite file types).