SI batteries replacement
SI batteries replacement
Can anyone verify which way I should mount the 2 batteries because I forgot to mark down the + and - terminals on the SI board before the they were removed ? I have an 88 M5 with the later SI board. TIA
How I did it (new style board -1/86 and after)...
Here's something I posted on the Other Place back in 2003. Steps 4 and 5 answer your question.
I have a lot of experience with the 1/86 and later style- the kind with the single red SI light. The boards I have worked with have two AA-sized NiCd batteries mounted between the two large light bulbs used to illuminate the cluster. Some of the later boards have a couple of lithium cells over to the side- I have no experience with those.
If you have the circuit board sitting in front of you, with the batteries at 12 o'clock, you'll notice each battery has a single prong on one side and two prongs on the other. You won't find these batteries at Radio Shack.
The single prong is on the positive side. What I did was unsolder all six prongs, using a combination soldering iron/solder sucker from Radio Shack. This gadget looks like a soldering iron with a red squeeze bulb.
Also at Radio Shack, I bought two AAA-sized NiCd cells (not AA like the originals- I'll explain why later) and an enclosed AAA holder with a sliding cover. While I was there, I also bought a pack of 1" x 3" Superlock Fasteners, which are like Velcro except that both halves are the same (not one part fuzzy and one scratchy, like Velcro), and it sticks to itself with more of a vengeance than Velcro does.
So here's what you do:
1. Start charging those AAA NiCds.
2. Unsolder the six prongs of the old batteries and pry them out of the board, along with the batteries.
3. Inspect and clean the surrounding area on the board. Check the various solder joints and IC pins in that area for continuity, and reflow anything that needs it.
4. Of the six holes left by the old batteries, you are concerned with only two. If you are looking at the board with the component side up and the battery position at 12 o'clock, the two holes you are interested in are the upper and lower ones on the left. Ignore the middle hole, and the holes on the right.
5. Solder the red wire from the battery holder to the lower hole, and the black wire to the upper hole. Stick the ends of the wires down through the hole from the component side of the board. If you messed up the upper hole while removing the old batteries, solder the black wire to the pin IMMEDIATELY to its left (not the leg of the adjacent component). If you messed up the lower hole, solder the red wire to the pin just above and to its left.
6. Now clip about 3/4" of Superlock and stick it to the back of the battery holder, so the long axes of the holder and the Superlock are parallel. Stick it a little toward the end furthest from the wires, about 1cm from the end.
7. Now rest the white plastic back on top of the circuit board, and clip another 3/4" of Superlock and stick it to the back of the cover, about 1/4" to the left of the hole for the large blue and yellow connectors.
8. Now reassemble. The first thing to do is stick the battery holder through the L-shaped hole in the middle of the back. Stick it through at the angle in the L, with the Superlock facing 1 or 2 o'clock (or just take the back off the holder, for more clearance). I chose AAA cells so the holder could fit through that hole.
9. With the back firmly attached to the circuit board, stick the battery holder onto the Superlock on the back, with the wires facing upward. It may look like a better place would have been toward the top of the back, but the ventilation ductwork in the car would have interfered when you tried to reistall it in the dashboard.
10. Put the fully charged batteries into the battery holder.
You're done. Unless it doesn't work, in which case you're just getting started...
I have a lot of experience with the 1/86 and later style- the kind with the single red SI light. The boards I have worked with have two AA-sized NiCd batteries mounted between the two large light bulbs used to illuminate the cluster. Some of the later boards have a couple of lithium cells over to the side- I have no experience with those.
If you have the circuit board sitting in front of you, with the batteries at 12 o'clock, you'll notice each battery has a single prong on one side and two prongs on the other. You won't find these batteries at Radio Shack.
The single prong is on the positive side. What I did was unsolder all six prongs, using a combination soldering iron/solder sucker from Radio Shack. This gadget looks like a soldering iron with a red squeeze bulb.
Also at Radio Shack, I bought two AAA-sized NiCd cells (not AA like the originals- I'll explain why later) and an enclosed AAA holder with a sliding cover. While I was there, I also bought a pack of 1" x 3" Superlock Fasteners, which are like Velcro except that both halves are the same (not one part fuzzy and one scratchy, like Velcro), and it sticks to itself with more of a vengeance than Velcro does.
So here's what you do:
1. Start charging those AAA NiCds.
2. Unsolder the six prongs of the old batteries and pry them out of the board, along with the batteries.
3. Inspect and clean the surrounding area on the board. Check the various solder joints and IC pins in that area for continuity, and reflow anything that needs it.
4. Of the six holes left by the old batteries, you are concerned with only two. If you are looking at the board with the component side up and the battery position at 12 o'clock, the two holes you are interested in are the upper and lower ones on the left. Ignore the middle hole, and the holes on the right.
5. Solder the red wire from the battery holder to the lower hole, and the black wire to the upper hole. Stick the ends of the wires down through the hole from the component side of the board. If you messed up the upper hole while removing the old batteries, solder the black wire to the pin IMMEDIATELY to its left (not the leg of the adjacent component). If you messed up the lower hole, solder the red wire to the pin just above and to its left.
6. Now clip about 3/4" of Superlock and stick it to the back of the battery holder, so the long axes of the holder and the Superlock are parallel. Stick it a little toward the end furthest from the wires, about 1cm from the end.
7. Now rest the white plastic back on top of the circuit board, and clip another 3/4" of Superlock and stick it to the back of the cover, about 1/4" to the left of the hole for the large blue and yellow connectors.
8. Now reassemble. The first thing to do is stick the battery holder through the L-shaped hole in the middle of the back. Stick it through at the angle in the L, with the Superlock facing 1 or 2 o'clock (or just take the back off the holder, for more clearance). I chose AAA cells so the holder could fit through that hole.
9. With the back firmly attached to the circuit board, stick the battery holder onto the Superlock on the back, with the wires facing upward. It may look like a better place would have been toward the top of the back, but the ventilation ductwork in the car would have interfered when you tried to reistall it in the dashboard.
10. Put the fully charged batteries into the battery holder.
You're done. Unless it doesn't work, in which case you're just getting started...
Good writeup. I've been looking for this for a while now.
Has anyone ran long battery wires and put the battery pack in a accessible place where they can be changed without removing the cluster? Like just above the kick panel above your shins? Or over into the glovebox? Any other places?
Or is this a dumb idea? Todays batteries should outlast the car, right?
Has anyone ran long battery wires and put the battery pack in a accessible place where they can be changed without removing the cluster? Like just above the kick panel above your shins? Or over into the glovebox? Any other places?
Or is this a dumb idea? Todays batteries should outlast the car, right?
I haven't. I figure it'll be years before I have to deal with the batteries again. BMWs poor soldering job on the instrument cluster, and my subsequent hacks, ensure that I'll be in there pretty often anyway. Since I'm going to be removing the cluster often, I'd rather have the batteries come with it.no2tracks wrote:Has anyone ran long battery wires and put the battery pack in a accessible place where they can be changed without removing the cluster? Like just above the kick panel above your shins? Or over into the glovebox? Any other places?
Don't count on it. In fact, count on the car still being around when NiCd batteries are no longer available, due to legislation or lack of interest.no2tracks wrote:Or is this a dumb idea? Todays batteries should outlast the car, right?
Re: How I did it (new style board -1/86 and after)...
RonW wrote: Sep 13, 2008 12:10 AM Here's something I posted on the Other Place back in 2003. Steps 4 and 5 answer your question.
I have a lot of experience with the 1/86 and later style- the kind with the single red SI light. The boards I have worked with have two AA-sized NiCd batteries mounted between the two large light bulbs used to illuminate the cluster. Some of the later boards have a couple of lithium cells over to the side- I have no experience with those.
If you have the circuit board sitting in front of you, with the batteries at 12 o'clock, you'll notice each battery has a single prong on one side and two prongs on the other. You won't find these batteries at Radio Shack.
The single prong is on the positive side. What I did was unsolder all six prongs, using a combination soldering iron/solder sucker from Radio Shack. This gadget looks like a soldering iron with a red squeeze bulb.
Also at Radio Shack, I bought two AAA-sized NiCd cells (not AA like the originals- I'll explain why later) and an enclosed AAA holder with a sliding cover. While I was there, I also bought a pack of 1" x 3" Superlock Fasteners, which are like Velcro except that both halves are the same (not one part fuzzy and one scratchy, like Velcro), and it sticks to itself with more of a vengeance than Velcro does.
So here's what you do:
1. Start charging those AAA NiCds.
2. Unsolder the six prongs of the old batteries and pry them out of the board, along with the batteries.
3. Inspect and clean the surrounding area on the board. Check the various solder joints and IC pins in that area for continuity, and reflow anything that needs it.
4. Of the six holes left by the old batteries, you are concerned with only two. If you are looking at the board with the component side up and the battery position at 12 o'clock, the two holes you are interested in are the upper and lower ones on the left. Ignore the middle hole, and the holes on the right.
5. Solder the red wire from the battery holder to the lower hole, and the black wire to the upper hole. Stick the ends of the wires down through the hole from the component side of the board. If you messed up the upper hole while removing the old batteries, solder the black wire to the pin IMMEDIATELY to its left (not the leg of the adjacent component). If you messed up the lower hole, solder the red wire to the pin just above and to its left.
6. Now clip about 3/4" of Superlock and stick it to the back of the battery holder, so the long axes of the holder and the Superlock are parallel. Stick it a little toward the end furthest from the wires, about 1cm from the end.
7. Now rest the white plastic back on top of the circuit board, and clip another 3/4" of Superlock and stick it to the back of the cover, about 1/4" to the left of the hole for the large blue and yellow connectors.
8. Now reassemble. The first thing to do is stick the battery holder through the L-shaped hole in the middle of the back. Stick it through at the angle in the L, with the Superlock facing 1 or 2 o'clock (or just take the back off the holder, for more clearance). I chose AAA cells so the holder could fit through that hole.
9. With the back firmly attached to the circuit board, stick the battery holder onto the Superlock on the back, with the wires facing upward. It may look like a better place would have been toward the top of the back, but the ventilation ductwork in the car would have interfered when you tried to reistall it in the dashboard.
10. Put the fully charged batteries into the battery holder.
You're done. Unless it doesn't work, in which case you're just getting started...
Can you please tell me which voltage did you use in your batteries. 1.2v or 1.5v?
-
Blue Shadow
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- Joined: Feb 12, 2006 12:00 PM
- Location: SE PA
Re: How I did it (new style board -1/86 and after)...
Battery chemistry determines the 1.5 vs 1.2V. A NiCd battery will be 1.2V per cell. NiCd batteries are what were used in the two battery SI boards.Opye47 wrote: Jul 23, 2024 5:53 PM
Can you please tell me which voltage did you use in your batteries. 1.2v or 1.5v?
https://electrouniversity.com/aa-battery-voltage-chart/
Re: How I did it (new style board -1/86 and after)...
Blue Shadow wrote: Jul 23, 2024 10:23 PMBattery chemistry determines the 1.5 vs 1.2V. A NiCd battery will be 1.2V per cell. NiCd batteries are what were used in the two battery SI boards.Opye47 wrote: Jul 23, 2024 5:53 PM
Can you please tell me which voltage did you use in your batteries. 1.2v or 1.5v?
https://electrouniversity.com/aa-battery-voltage-chart/
Thank very much!! And when he/she says that the components have to be up side and 12 o clock. Means that the batteries have to be in vertical or horizontal. That part still hasn't made me completely clear. For example. The batteries in vertical will look like this = one over the other and horizontal will look like || like side by side and not over the other. So which Guidance is correct, I'm sorry for asking so many questions.