Retrofit 08 Instrument Cluster?

[rob13572468]

charlie, if you could check whatthe bit map patterns are for the progressive shift lights that would be excellent... I am already started writing the code for the translator but need to know what a few of the bits do... here is the known mapping:

400h	8	AA BB CC DD EE FF GG HH

		AA -----------------------> adjusted speed ~= d(XXh)-11d (61h-->97-11=86 mph)

		   BB --------------------> unused (always 00)

		      CC DD --------------> tach rpms [d(CCh)*256]+d(DDh) 06 D2 = 1746 rpm

			    EE -----------> fuel level (00=empty, FF=full)

			       FF --------> engine temperature ~= d(XXh)-14d (D0-->208-14=194F)

				  GG -----> MIL (04-oil, 02-engine, 01-shift)

				     HH --> unused (always 00)

bitmask patterns:

01  00000001  shift light
02  00000010  engine light
04  00000100  oil light
08  00001000
10  00010000
20  00100000
40  01000000
80  10000000

the can trace that you posted in the other thread shows that at least bits 3 and 7 are used (40 and 08) in the MIL byte (byte 7 of 8). Also your trace shows that byte 8 (the one that reads 20) is now used whereas in 2005 it was not.

Finally the text frame only shows 7 bytes being able to be sent... have you ever seen a message on the cluster that is bigger than 7 bytes and if so can you post a quick trace.

thanks.

[dstevens]

My measurments showed:

AA -> speed (mph * 1.5)

FF -> temp (degs C * 1.6 + 64)

It could be coincidence that my speedo was inaccurate by the difference between kph and (mph * 1.5). I believe the temp calculation is accurate - the 1.6 multiplier in essence converts from dec to hex.

[charliex]

speed is just km/h

rob i'll work on the bitfields.

[dstevens]

To get my dash to read 100 mph I had to send 150 decimal to the cluster. Sending the speed in kph makes it over-read by 8%. The two dashes I tested had errors of 7.5% and 8% as measured by GPS, so I figured the 8% was a standard Lotus speedometer over-reading fudge factor.

[charliex]

it is, the error is set in the dash.

[IXLR8]

Originally Posted by ZAMMY1

the depth of technical expertise on this forum is stunning, as is the spirit of cooperation among competitors.
my hat's off to you all.
sam

Amazing, isn't it?

[charliex]

the 0x401 text frame is fixed size, the mesages are really short, like FAULT, LH TYRE(or something like that, i'd have to go check the actual text)

there is more data in the can stream than there was originally.

remember though the localised version of the speed/temps for 08+ is set in the can frame, unlike previous years where its fixed to metric and translated by the cluster

you can alternate it obviously.

[charliex]

Current strings are

"LTC OFF "
"LTC ON "
" LTC "
" % Slip"
"Launch "
"LF LOW "
"RF LOW "
"LR LOW "
"RR LOW "
"TPMS "
"FAULT "

my guess is with the spacing they're not clearing the display and overwriting it with spaces instead, so the if the message is smaller than the last it has to be padded with spaces, thats typical with LCD's

[charliex]

Updated my 08 cluster wiring diagram.

[charliex]

Still a work in progress

unsigned char m_Speed1;   /// Instrument speed
unsigned char m_Speed2;   /// Mileage speed
unsigned short m_RPM;      /// Engine speed
unsigned char m_Fuel;       /// Fuel level, not desloshed
unsigned char m_Coolant;   /// Coolant temp
unsigned char m_CAN08_BFa;   /// shift lights, mil, oil pressure, tc, config
unsigned char m_CAN08_BFb;   /// service, coolant overtemp, fog warning

m_CAN08_BFa

unsigned char m_Shift:3;  /// shift lights
unsigned char m_MIL:1;    /// fault
unsigned char m_Oil:1;     /// oil warning
unsigned char m_TC:1;    /// TC
unsigned char m_Config:1; /// localisation bit

m_CAN08_BFb

unsigned char m_Service:1; /// service light
unsigned char m_NA:3;
unsigned char m_CoolantWarn:1; /// over temperature
unsigned char m_FogLights:1; /// fog light  open circuit

[dstevens]

2005	2008	Chng	Color	Function
C7	B7	**	U	CANL
C1	A7	**	R	CANH
A2	A2		BP	GND
B11	B11		PW	Lightsbuzzer
C5	A10	**	RO	Illum
B6	B6		RO	Illum
B9	B9		RW	Illum switch
A9	A9		UW	Main beam
A8	A8		RY	Rearfog
B12	B12		BP	SRS
A10	A4	**	NY	Alt
B3	B3		BY	ABS
B1	B1		BW	Brake
B4	B4		BP	Seat
B8	B8		GR	Fuse C3
A5	A5		G	Ign power
A12	A12		GW	Indicator
A11	A11		GR	Indicator
A3	A3		P	Fuse 8
B7	A6	**	PK	Alarm

Here's my take on the wiring differences. My diagram is a little unclear on the designations (thanks for the fine photocopy Lotus), so I'd need to verify by wire color. The only thing which seems odd is that there are two connectors in the 05 cluster, but A, B and C designations.

[charliex]

they're rows.

the 08 drops one.

i posted a clearer version of the 2005-2007 diagram, i marked some of the changes with *'s, here it is again

[dstevens]

I've corrected my initial diagram - it seems there only 5 wiring changes to make.

I've got a 2008 dash on the way. Next week is full but I should be able to look at it starting on the 26th.

[rob13572468]

Originally Posted by dstevens

My measurments showed:

AA -> speed (mph * 1.5)

FF -> temp (degs C * 1.6 + 64)

It could be coincidence that my speedo was inaccurate by the difference between kph and (mph * 1.5). I believe the temp calculation is accurate - the 1.6 multiplier in essence converts from dec to hex.

Those measurements seem to make better sense. I did the original calculations in 2005 and looking back it makes obvious sense that the values would have been in km and celcius.

[rob13572468]

Originally Posted by charliex

Still a work in progress

unsigned char m_Speed1;   /// Instrument speed
unsigned char m_Speed2;   /// Mileage speed
unsigned short m_RPM;      /// Engine speed
unsigned char m_Fuel;       /// Fuel level, not desloshed
unsigned char m_Coolant;   /// Coolant temp
unsigned char m_CAN08_BFa;   /// shift lights, mil, oil pressure, tc, config
unsigned char m_CAN08_BFb;   /// service, coolant overtemp, fog warning

m_CAN08_BFa

unsigned char m_Shift:3;  /// shift lights
unsigned char m_MIL:1;    /// fault
unsigned char m_Oil:1;     /// oil warning
unsigned char m_TC:1;    /// TC
unsigned char m_Config:1; /// localisation bit

m_CAN08_BFb

unsigned char m_Service:1; /// service light
unsigned char m_NA:3;
unsigned char m_CoolantWarn:1; /// over temperature
unsigned char m_FogLights:1; /// fog light  open circuit

awesome, thanks charlie.. that should be enough for me to put together an interface and then we can start testing.

incidentally one more question:

unsigned char m_Speed2;   /// Mileage speed

i remember back in 2005 there was a question of how the cluster changed the odometer... going back to my log data I never see that byte change...it always reads 00..

[dstevens]

The 05 cluster increments the odometer by integrating speed over time. If you get the speed accurate then the odometer under reads - which shows me the over-speed is deliberate from Lotus.

Also with the 08 cluster a 180 mph speedo is a waste of time when the maximum it can ever show is 158 mph (255 kph). I guess that will be a little higher with the inaccuracy - about 170 mph.

[charliex]

The second speed byte is because the 08 cluster can send speed in km/h or mph since the cluster doesn't necessarily know which its using, it uses the second byte which is fixed at km/h

The 08 cluster can show 180MPH too, so its not a waste of time, well at least for those that can reach/ exceed that speed

[jwood]

Could any of you tell me the weight of the 06 and 08 cluster it's self? I'm wondering because it seems like an ultra thin & light LCD could look almost the same but save a little weight. As well as give you a load of extra functionality.

[NomisR]

Originally Posted by jwood

Could any of you tell me the weight of the 06 and 08 cluster it's self? I'm wondering because it seems like an ultra thin & light LCD could look almost the same but save a little weight. As well as give you a load of extra functionality.

Only in a Lotus forum..

[LBC111]

Charlie, Rob, et al... Good job gentlemen!!! Can you please PM me when you have this all figured out? I would love to convert my 07 cluster, and will have Qais install it for me.