Having helped engineering students build a van that uses scanning lasers to measure pavement irregularities, GPS location, OCR detection of roadway sign inventory, all at 60 mph, with 250 amp alternator to keep up with the UPS for the servers, which all have 100% RAM drives (hard drives don't like pot holes), and a fresh sample every 4mm of horizontal travel... I can attest to the idea that anything can be enhanced. But put the highway divsion manager in a truck with the worst shocks and he'll figure out pretty quick that funds need to be set aside for repaving road "X".

 

Take said sending unit and provide appropriate voltage to the input. Heat the sending unit and record the output in increments up to overheat conditions of the LR. Record the data. Take a temperature gauge and apply voltage to the instrument and record pointer position for each increment of voltage applied. Correlate where you want said temperature to read on the gauge based on voltage needed. Program the micro controller to provide the output to the gauge based on the recorded values needed. The logic is very basic to figure out. You could do the basic assembly on a bread board for the initial trial.

Really pretty simple stuff I learned in software engineering classes 15 years ago. That is no harder than reflashing the ECU with a new .bin file for fuel/timing tables. Anywho, I hope you can provide the hardware for others to use.

Good Luck.

A Happy non owner who sold his Disco.

MAK

 

True on many counts. Not the way I'm going to do it but it would work, with one HUGE exception.

I couldn't disagree more with your assertion that it is "really simple", unless you have all the source code and index tables and dev tools for the ECU. I'm betting this is almost impossible to legally get.

No way I'm re-flashing my ECU even if I knew how to, which I don't.

I've been doing Electrical Engineering work for over 30 years and hold several patents,,, but nope,, doing brain surgury on my LR w/o any knowledge of the hardware and software platform on which it's built is definitely not "simple stuff",, for me at least.

I'll let some other really smart guy with way more information and time on their hands than I have to get sucked down THAT rabbit hole, thank you very much.

 

I'm glad people take an interest in the temp gauge, and I hope some will look at the Ultra Gauge which will not only tell the facts on the temp, in disgusting digital, it will also let you program alarm set points, display voltage, mpg, etc. And read and reset codes. In the old school days we could see the temp gauge moving from "m" to "P" and we knew that meant something. The current ECU driven system hides the coolant temp from the owner until it is a big problem. Not surprising, as Rover feels we have no ability to read an oil PSI gauge either.

For those with inquiring minds, the specs on the sensors are in this LR document on fuel injection systems (Lucas, GEMS, and Bosch).

 

Thanks for the reply,

I hold several patents in the printing industry as well. Then again, it has nothing to do with the LR. My response was in regards to NOT using the ECU output for the Temp reading. But, taking the existing hardware and applying a new output signal to achieve the desired results. You have misconstrued what I have said regarding the mod.

Here is the software for fuel mapping and timing for the Bosch ECU.
www.thePro2DMEeditor.com - Motronic Map Editing Software - Tools for the Tune-It-Yourselfer...

For the record, if I were to modify the signal, I could use any temperature sending unit I wanted within reason.

I am an average guy with some basic smarts. This is not rocket science by any stretch of the imagination. There is no other way to determine gauge position without applying voltage and recording the needle position. Anyone would be guessing without applying basic electrical principals to this idea. I figured that when I mentioned the bread board that you would have known it is used in circuit design prior to PCB manufacturing. Hence, not using the ECU.

I have no beef with your idea. It's a good one.

MAK

 

Wow that's great info. But honestly still not interested in mucking w/ECU.

Actually there are two ways to move a std dial:
1-Apply a voltage
2-Apply a pulse train. (this is the method LR uses (PWM))

Good stuff, thanks,,, but think I'll leave that level of hacking to others...

 

2Discos-

Have you made any progress with this project? I have an UltraGauge but the dumbed-down factory gauge bugs me ... a lot. I'd love to be able to modify it so that it has something other than three states. Thanks.

-Rob

 

Well, the coolant temp sensor for the D2 has two sensors in one package, four terminals. I think the second sensor is used in Rangies. You could take the un-used sensor, and combine it with a suitable few resistors, and drive the stock gauge. This leaves the oem ECT sensor to drive the ECU and do all it is supposed to to do. Ohms law is usually faster than most programmers.

BTW - definition of programmer: a person who takes caffeine and pizza and turns it into software.