| Author | Message | |||
     Alistair Riddell Experienced User Username: ariddell Post Number: 15 Registered: 1-2013 |
Hello All, 25955 has developed a flaw in the adjustment capabilities of the drivers seat, comfortable as it is (although greatly assisted in this respect by the addition of some $40 leather headrest bolster cushions from China), it has ceased to perform any forward/back adjustments in its previously motorised manner. I get the click of a relay when attempting to adjust but nothing more. Until recently this has been working fine and the memory buttons were also working as they should. Would this sound like the failure of the seat ECU being the likely cause as I gather is a reasonably common issue? Is it a straightforward operation to remove the seat squab to investigate further? It looks to be fairly easy but I am rather terrified of damaging the leather. Thanks, Al | |||
| David Thomas Experienced User Username: davidthomas Post Number: 32 Registered: 5-2007 |
Hi Al! If you decide you need professional assistance with this I can PM you with a recommendation. Cheers, David | |||
| Paul Yorke Grand Master Username: paul_yorke Post Number: 1081 Registered: 6-2006 |
Hi Alistair, Most often it will be a seat memory unit. As you still have some movement you can undo the rubber strap and claw on your squab and should be able to lift the front to get the unit out. Otherwise two screws at the bottom of the back cover of the seat. Lift the cover up to unclip it at the top and remove. This will reveal two more screws close to where the first two were removed. If your passenger side is still working, you can fit the passengers side unit to the drivers side to test that it is not the seat or switches at fault. Chances are the battery has leaked. Here are a few photos of what to look for, but it's usually very apparent! https://www.facebook.com/photo.php?fbid=558041080902410&set=a.493227054050480.107909.480142005358985&type=1&theater While you have the passengers side unit out replace the battery (or remove if you don't use the memory) function) in that side to. PM if you'd like a quote for an exchange unit and a spare battery. | |||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2861 Registered: 4-2003 |
As Paul points out, look to the seat memory unit. A word or two of encouragement though. If the batteries have not leaked or have already been replaced with NiMH, then there are the open relays in the memoru ECU box probably bvausing annoyance. If the batteries are still NiCd then replace them with NiMH once the system functions again as NiCDs leak when old. The NiMHs last a very long time and never leak. That the seats adjust at all suggests a rather trivial problem here. With the module removed, and the cover off, flick each of the contacts on the (16?) open power relays on the ECU board with an instrument screwdriver. One or two may be stuck and free up instantly solving the issue. If so, some further cleaning of the contacts may make you very happy as the seat controls return to function. This happens especially in damp and cold conditions after a period of disuse. RT. nb this is practical saviour not theory. | |||
| Alistair Riddell Experienced User Username: ariddell Post Number: 16 Registered: 1-2013 |
Thanks all, I will see about removing both units this evening and do some further investigation as to the status of the ECUs and relays. I don't think the memory function on the passenger side works but there are certainly no issues with the controlled adjustment of the seat on that side. Regards, Al | |||
| Alistair Riddell Experienced User Username: ariddell Post Number: 17 Registered: 1-2013 |
Well, as expected the advice from the forum has once again been spot on, the battery in my drivers side ECU has leaked and damaged the tracks of the adjacent transistor array chip. I've positioned the passenger side seat into a suitable position for it to remain static until the unit can be repaired and have swapped its ECU to the drivers side. Incidentally my passenger side unit has been subject to a swap at some point in the past as it is dated 1996 on an attached sticker, although contains the same type of battery as the drivers side unit. Where would I get hold of replacement NiMH battery packs of suitable type, is this the sort of item a Jaycar or similar electronics shop would be expected to carry or something more specialist? Thanks, Al | |||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2863 Registered: 4-2003 |
Al, That battery pack is used in older wireless phones. It is available in NiMH from the Battery Factory or Jaycar. They come as a pack of 3 cells, 3,6V with leads, so put a plastic sheath over the board and solder the leads to the battery positions. Some silicone RTV will secure it all. Having leads rather than posts is an advantage as you can further protect the circuit board for the unlikey failure of a NiMH battery. The transistor array (ULN2003A etc) is available at Jaycar. The modules usually respond to a new array. Click below to download the data sheet. RT.
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| Richard Treacy Grand Master Username: richard_treacy Post Number: 2865 Registered: 4-2003 |
If the above pdf file will not download, this extract may help.
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| Alistair Riddell Experienced User Username: ariddell Post Number: 18 Registered: 1-2013 |
Thanks RT, all sounds eminently DIYable in that case, I'll procure the needed components and enlist the assistance of a friend with far superior soldering skills to mine to do the install and see how we go. Rgds, Al | |||
| Richard Treacy Grand Master Username: richard_treacy Post Number: 2867 Registered: 4-2003 |
I suggest that all interested in this topic refer to the Technical Library. Early battery replacement will save lots of pain. Here is the relevant link: http://rrtechnical.info/sz/sz87/memory_seats/seat_mirror_memory.htm RT. ps: time to change the battery pack on my Continental R as I have not looked at it yet. On my Turbo R I fitted new NiCd batteries around 2000, but changed them for Ni-MH several years ago. |
