In doing various repairs on my XK8, I have generally found more
useful info on the X300 Forum. There seem to be a larger number of
DIY’ers here. So there may be a few who would be interested in how
I recently troubleshot and repaired my defective Power Seat Control
module (I had lost half of the tilt function for the driver’s seat)
http://tinyurl.com/yhu8st4--
Glen - 69 E-type OTS, 2000 XK8, 59 MGA
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
In reply to a message from Glen Jarboe sent Tue 23 Feb 2010:
Is the drivers seat ECU on the X300 the same as on the XK8?
All seat functions on my drivers memeory seat do not operate
(fuses are OK)
Has anyone with a similar problem opened up the X300 ECU and
found a fault?–
JDA. Westminster Blue 1995 Sovereign 4.0 Auto
Glasgow, United Kingdom
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –
In reply to a message from JDA sent Wed 24 Feb 2010:
Hi All,
I also have no drivers seat funtions. PO gave me a spare seat and I
have been following this with great interest. I have memory also
but never use it. Too much crap moving around something bound to
break! If it ever warms up around here I’ll pull the seat ecu and
check the board. Thanks for the info.
Darrell–
The original message included these comments:
All seat functions on my drivers memeory seat do not operate
(fuses are OK)
–
Darrell 1978 XJ-S 1995 X-300 Delavan Wi.
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –
In reply to a message from JDA sent Wed 24 Feb 2010:
I saw several modules on ebay. It appears that all modules since
the late 90’s have the same part number with the exception of the
last letter (D, E, F or G - my 2000 XK8 ends in G). Most of the
modules I found are for X-types and X30X’s. I have no idea what
the difference might be among the various modules, maybe just the
programming.
As I mentioned, the modules are easy to remove and open up. The
two halves of the plastic case are held together by ten plastic
tabs. Just be careful to not pry against the control board in
easing back the tabs. Once the halves are separated, the board
simply slides out.
If there is a fault on your board, it may very difficult to see -
just a tiny spot in one of the tracks. Of course, there are lots
of other possible failures such as a failed chip. Maybe I was
just lucky that mine was easy to see and repair.
As I mentioned, there are five relays (four of them sit side by
side, the other is on the opposite side of the board). I’m not
sure which relay goes with which funtion of the seat, although I am
pretty sure that Relay # 1 is related to the tilt function (the
open line on my board led to Relay # 1).
The relays are dual relays (two relays in each case) to control the
two directions of its associated motor, so each relay will have two
tracks leading to the microchips near the edge of the board. The
PCB tracks are on the top surface and run under the relay, but the
solder lugs are on the bottom making it difficult to know for sure
which lug of the relay should have continuity to a pin of its
associated chip.–
Glen - 69 E-type OTS, 2000 XK8, 59 MGA
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –
In reply to a message from Glen Jarboe sent Thu 25 Feb 2010:
Thanks for the details, I have organised a seat ECU from a
local breaker and will experiment–
JDA. Westminster Blue 1995 Sovereign 4.0 Auto
Glasgow, United Kingdom
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –
This exactly what was wrong with my controller unit
Fixed it just now
11 years after this initial thread 
Thanks
From my reading on this forum and elsewhere, the most common problem with seat/seat memory not working is dead/broken potentiometers.
My 2 cents, FWIW 