I've been asked to re-post this as it did not make it over to the "new board". So here it is...
Cluster Removal / SI Board Replacement
If you can not reset your service light (see another post FYI) then you have to change the SI board batteries. Here is a detailed FYI on how to do it.
These batteries are intended to save the service indicator memory in case you disconnect the car's main battery. When the car is running it recharges the SI board batteries. But over time they lose their ability to hold a charge and that is when the SI system starts to go haywire. The LED's will come on and cannot be reset. Eventually your gauges can start to act funny (tach, temp etc.) At his point it is time to replace the batteries. BMW did not make this particularly easy, the whole instrument cluster has to be pulled out to get at the batteries. Some people solder in a remote connection so that the batteries can be stored farther down above the pedals. This makes them much easier to access the next time they need replacing. However, the modern class of batteries is far superior to what our cars originally came with. The new (NiCad) batteries should last for quite some time.
1) At the bottom of the photograph you can make out the lower trim panel. This is a piece of hard plastic which runs below the steering column. There is another large cover panel farther down (not shown) which covers up the pedal cluster and clutch master cylinder. This must be removed first by unscrewing the quarter turn plastic screws along its upper edge. Disconnect the "bong" and slide out this large cover panel. Then you can remove the trim panel shown above. This is a little tricky but not too bad. The two arrows at the bottom show a threaded stud (left) and a threaded stud with a knurled knob screwed onto it (right). These studs are molded into the plastic trim piece. The studs go into the two holes in the dash shown by the upper two arrows. The knurled knobs screw onto the studs from behind. So to undo them you have to reach up and under the bottom of the dash. They can then be loosened by hand. Once the knurled knobs are removed you can pull off the lower trim panel.
2) Now it's time to remove the cluster trim. This is a hard plastic trim piece which goes around the instrument cluster. The six arrows above point out the six philips screws which hold the cluster trim in place. The lower screws are normally hidden by the lower trim panel but are now exposed. The upper two screws are always visible. The outer screws highlighted by the blue arrows not only hold the cluster trim in place, they also hold the actual instrument cluster in place (along with two more screws at the top which are hidden by the trim). Remove the six screws with a small Philips screwdriver and pull off the cluster trim.
3) The yellow circles show the mounting tabs on the instrument cluster. The upper two screws which secure the cluster to the dash are inserted through these tabs. Once the cluster trim has been removed (step 2) the upper mounting screws can be removed with a Philips screwdriver. Then the instrument cluster is free to be pulled out of its receptacle. Some people say you can remove the instrument cluster without removing the steering wheel. This may be so. But since it is very easy to scratch the clear plastic cover on the cluster why make things more difficult than they need to be? Especially when removing the steering wheel is a 30 second procedure? Of course if you have an airbag then this is a little more involved. In any case, I did not hesitate to pull the steering wheel before beginning this job. I found it easiest to remove the cluster from the dash by rotating it out from the top (as shown below).
4) Once the instrument cluster is pulled free of the dash you will be able to move it about 8-10 inches before the wires going to the back of the cluster impede further progress. You must now remove the electrical connectors from the back of the cluster in order to completely pull it free. One of the electrical connectors is shown above. There is a locking tab (black) which must be pried out before the connector can be pulled off. I used a screw driver for this purpose but I suppose it could be accomplished with a strong set of fingers.
Although most of the connectors are color coded you must still pay attention what goes where as one of the connectors (the green one) is ambiguous in terms of its placement. Be VERY careful not to scratch the clear plastic cluster face while pulling the electrical connectors, as this is when it is most likely to get damaged. Note the soft rag in the picture.
5) Nothing too much to show here except a somewhat shaded view of the dash receptacle after removal of the instrument cluster. The yellow and blue electrical connectors can be seen.
6) Now the instrument cluster is free and can be carefully placed face down on a soft towel. The two mounting tabs which protrude out from the top of the cluster actually prevent it from lying flat, but you still have to watch out. The plastic face on the cluster is very easy to scratch - I cannot stress this enough.
We now want to split the cluster (separate the front from the back). This is done by removing 9 small Philips screws from the back of the cluster, 8 around the periphery and one in the center. Several of the Philips screws are pointed out by the red arrows above. The blue arrow shows the row of "idiot lights" (abs, battery etc...) The bulbs for these lights screw in from behind and can in theory be replaced from behind the dash without removing the cluster.
Also note the color coded electrical sockets (white, yellow, blue, and green). There is a gray connector which goes into the black socket as well. It is the green connector/socket combination which has several possible combinations and must be observed upon removal.
Once the nine Philips screws are removed you can carefully separate the blue cluster back from the cluster face. Watch out for the gauge needles!
7) This is the previously shown light blue back of the instrument cluster which has now been flipped over and placed on the towel. Note how exposed the gauge needles are - they are easy to knock out of position or bend at this time. The SI Board is actually part of the front of the instrument cluster but there are some interesting details to be seen here. The blue arrows point out the orange bulbs which light the instruments and give the cluster that characteristic BMW hue at night. I suppose this would be a good time to perform some preventative maintenance and replace these bulbs. The red arrow shows the electrical connector which accepts the prongs on the backside of the SI Board.
8) We now return our attention to the front of the instrument cluster (the clear plastic face). You can see the previously mentioned prongs on the back of the SI board (red arrow). The blue arrow highlights the single Philips screw which must be removed in order to pull the SI board free from the cluster face. The Philips screw holds down a small plastic bracket. Once the screw is removed, pull out the plastic bracket and then gently pull out the SI board. It must be pulled straight out. If it rocks sideways it will get jammed. On the left side of the SI board in this view there is a small electrical prong connector where the board plugs into the cluster face. This will automatically be disconnected as you pull out the board.
9) This is a slightly different picture of the back of the cluster face. It offers a better view of the SI board in its installed location (yellow rectangle). The plastic retaining bracket has been removed. The white arrow shows those pesky SI board batteries. Note the orange plastic pieces. The orange cluster light bulbs come to rest in the cut outs in these pieces. From there the light is distributed to the front of the gauges.
10) Last but not least - the SI Board. Below is a new SI board with lithium batteries and below is the old one. Note the blown battery on the old SI board (green circle). The light blue rectangle shows the actual service indicator LED's which appear on your dash display. These LED's are mounted on a separate circuit board which must be pulled out of the old SI Board and plugged into the new one. This is an easy task. The purple arrow shows the orientation of the SI Board relative to the driver.
Now, as they say, assembly is the reverse of removal. Just install the new SI Board into the cluster face and then retrace your steps. I did not have to reset the SI lights after replacing the SI Board. They reset themselves. GOOD LUCK!
Cluster Removal / SI Board Replacement
If you can not reset your service light (see another post FYI) then you have to change the SI board batteries. Here is a detailed FYI on how to do it.
These batteries are intended to save the service indicator memory in case you disconnect the car's main battery. When the car is running it recharges the SI board batteries. But over time they lose their ability to hold a charge and that is when the SI system starts to go haywire. The LED's will come on and cannot be reset. Eventually your gauges can start to act funny (tach, temp etc.) At his point it is time to replace the batteries. BMW did not make this particularly easy, the whole instrument cluster has to be pulled out to get at the batteries. Some people solder in a remote connection so that the batteries can be stored farther down above the pedals. This makes them much easier to access the next time they need replacing. However, the modern class of batteries is far superior to what our cars originally came with. The new (NiCad) batteries should last for quite some time.
1) At the bottom of the photograph you can make out the lower trim panel. This is a piece of hard plastic which runs below the steering column. There is another large cover panel farther down (not shown) which covers up the pedal cluster and clutch master cylinder. This must be removed first by unscrewing the quarter turn plastic screws along its upper edge. Disconnect the "bong" and slide out this large cover panel. Then you can remove the trim panel shown above. This is a little tricky but not too bad. The two arrows at the bottom show a threaded stud (left) and a threaded stud with a knurled knob screwed onto it (right). These studs are molded into the plastic trim piece. The studs go into the two holes in the dash shown by the upper two arrows. The knurled knobs screw onto the studs from behind. So to undo them you have to reach up and under the bottom of the dash. They can then be loosened by hand. Once the knurled knobs are removed you can pull off the lower trim panel.
2) Now it's time to remove the cluster trim. This is a hard plastic trim piece which goes around the instrument cluster. The six arrows above point out the six philips screws which hold the cluster trim in place. The lower screws are normally hidden by the lower trim panel but are now exposed. The upper two screws are always visible. The outer screws highlighted by the blue arrows not only hold the cluster trim in place, they also hold the actual instrument cluster in place (along with two more screws at the top which are hidden by the trim). Remove the six screws with a small Philips screwdriver and pull off the cluster trim.
3) The yellow circles show the mounting tabs on the instrument cluster. The upper two screws which secure the cluster to the dash are inserted through these tabs. Once the cluster trim has been removed (step 2) the upper mounting screws can be removed with a Philips screwdriver. Then the instrument cluster is free to be pulled out of its receptacle. Some people say you can remove the instrument cluster without removing the steering wheel. This may be so. But since it is very easy to scratch the clear plastic cover on the cluster why make things more difficult than they need to be? Especially when removing the steering wheel is a 30 second procedure? Of course if you have an airbag then this is a little more involved. In any case, I did not hesitate to pull the steering wheel before beginning this job. I found it easiest to remove the cluster from the dash by rotating it out from the top (as shown below).
4) Once the instrument cluster is pulled free of the dash you will be able to move it about 8-10 inches before the wires going to the back of the cluster impede further progress. You must now remove the electrical connectors from the back of the cluster in order to completely pull it free. One of the electrical connectors is shown above. There is a locking tab (black) which must be pried out before the connector can be pulled off. I used a screw driver for this purpose but I suppose it could be accomplished with a strong set of fingers.
Although most of the connectors are color coded you must still pay attention what goes where as one of the connectors (the green one) is ambiguous in terms of its placement. Be VERY careful not to scratch the clear plastic cluster face while pulling the electrical connectors, as this is when it is most likely to get damaged. Note the soft rag in the picture.
5) Nothing too much to show here except a somewhat shaded view of the dash receptacle after removal of the instrument cluster. The yellow and blue electrical connectors can be seen.
6) Now the instrument cluster is free and can be carefully placed face down on a soft towel. The two mounting tabs which protrude out from the top of the cluster actually prevent it from lying flat, but you still have to watch out. The plastic face on the cluster is very easy to scratch - I cannot stress this enough.
We now want to split the cluster (separate the front from the back). This is done by removing 9 small Philips screws from the back of the cluster, 8 around the periphery and one in the center. Several of the Philips screws are pointed out by the red arrows above. The blue arrow shows the row of "idiot lights" (abs, battery etc...) The bulbs for these lights screw in from behind and can in theory be replaced from behind the dash without removing the cluster.
Also note the color coded electrical sockets (white, yellow, blue, and green). There is a gray connector which goes into the black socket as well. It is the green connector/socket combination which has several possible combinations and must be observed upon removal.
Once the nine Philips screws are removed you can carefully separate the blue cluster back from the cluster face. Watch out for the gauge needles!
7) This is the previously shown light blue back of the instrument cluster which has now been flipped over and placed on the towel. Note how exposed the gauge needles are - they are easy to knock out of position or bend at this time. The SI Board is actually part of the front of the instrument cluster but there are some interesting details to be seen here. The blue arrows point out the orange bulbs which light the instruments and give the cluster that characteristic BMW hue at night. I suppose this would be a good time to perform some preventative maintenance and replace these bulbs. The red arrow shows the electrical connector which accepts the prongs on the backside of the SI Board.
8) We now return our attention to the front of the instrument cluster (the clear plastic face). You can see the previously mentioned prongs on the back of the SI board (red arrow). The blue arrow highlights the single Philips screw which must be removed in order to pull the SI board free from the cluster face. The Philips screw holds down a small plastic bracket. Once the screw is removed, pull out the plastic bracket and then gently pull out the SI board. It must be pulled straight out. If it rocks sideways it will get jammed. On the left side of the SI board in this view there is a small electrical prong connector where the board plugs into the cluster face. This will automatically be disconnected as you pull out the board.
9) This is a slightly different picture of the back of the cluster face. It offers a better view of the SI board in its installed location (yellow rectangle). The plastic retaining bracket has been removed. The white arrow shows those pesky SI board batteries. Note the orange plastic pieces. The orange cluster light bulbs come to rest in the cut outs in these pieces. From there the light is distributed to the front of the gauges.
10) Last but not least - the SI Board. Below is a new SI board with lithium batteries and below is the old one. Note the blown battery on the old SI board (green circle). The light blue rectangle shows the actual service indicator LED's which appear on your dash display. These LED's are mounted on a separate circuit board which must be pulled out of the old SI Board and plugged into the new one. This is an easy task. The purple arrow shows the orientation of the SI Board relative to the driver.
Now, as they say, assembly is the reverse of removal. Just install the new SI Board into the cluster face and then retrace your steps. I did not have to reset the SI lights after replacing the SI Board. They reset themselves. GOOD LUCK!