Temp gauge re-code

[Overboost]

Originally Posted by Purplefade

LoL - good advice for sure! I actually saved it twice as .bin and .bin1 - just in case Been bitten too many times by saving a minute...

When I first worked this temp gauge hex recode out on the E53, I made a couple of mistakes in the strings. It was nice to get back and then figure out where the mistakes were and correct them.

[Purplefade]

I just replaced my fog and reverse lights with LEDs and had pa soft loaded to turn off the cold check and figured what the heck, no time like the present!


Appreciate yours and crowz write ups, sure saved me a ton of time! Thanks!

[Overboost]

Originally Posted by Purplefade

I just replaced my fog and reverse lights with LEDs and had pa soft loaded to turn off the cold check and figured what the heck, no time like the present!


Appreciate yours and crowz write ups, sure saved me a ton of time! Thanks!

Crowz write up was a copy and paste from my instructions for him after I did mine.

[zboost]

Saw the topic yesterday and I just digged into that because this temp gauge really pisses me off the way BMW has left it to behave on E53 (and other models).

Good news here is that I found a really easy way on making the gauge work like it should, you don't need to change the EEPROM and bother with HEX code strings in LCM. All you need is to change one coding option. The right place to do this is the KOMBI module. I'm with the high cluster on E53 3.0d facelift model so this is KMBI_E38.C12 module in my case in NCS Dummy. Just find the KUEHLMITTELTEMP_ADC_WERT option wich is setting of the characteristic curve of the gauge. The values might differ, depending on your cluster and engine.



If you take a look on the default value kennlinie_03 you will see the HEX code is an exact match of the celsius positions of the gauge. Pay attention in the DATA string, it's the HEX values converted to DEC in celsius.

There is a pre-set option kennline_04, wich suits my needs perfect, select that and recode witn NCS Expert.



Values here are: 15 60 85-100 107 114. Those makes more sense.
Interesting why BMW chose a factory setting of kennlinie_03 instead of this?
Well, rebuilding/replacing an overheated engine could be costly in the local dealer I guess.

After recoding your cluster the gauge will behave correctly, tested it while driving with the hidden menu TEST 07 wich is the coolant temp sensor reading in real time and the values are spot on! Also I think you can add your own string and modify the values (keep the 00s in place), but in my case I found the given option of the curve good enough.

One more thing, after you recode you will need to change MOTOR_UEBERTEMP (overehating cluster alarm) in LCM module to 114 c celsius or lower! I was surprised to find out this setting was completely missing in my FSW_PSW.TRC after recoding KOMBI because it was now out of range. Default was 125_grad_celsius, I had it changed before to 115 c and it was still missing because the maximum temperature of the cluster gauge will be 114 c celsius. So you have to set that, just add new parameter before you load the .TRC in NCS Dummy and hit Update module and recode.



Good luck

[zboost]

Pictures of the gauge now

60c - https://dl.dropboxusercontent.com/s/...1x/60.jpg?dl=0
79c - https://dl.dropboxusercontent.com/s/...0d/79.jpg?dl=0
90c - https://dl.dropboxusercontent.com/s/...24/90.jpg?dl=0

[oldskewel]

Great info. I have not seen this before. I expect it will be easier and safer for people to make this change vs. finding and editing the hex code values in both places, etc.

More info for others in this useful thread:
https://xoutpost.com/bmw-sav-forums/...rmostat-6.html

One question I had when doing it manually there, that I never got an answer for, is what are the in-between values between those breakpoint settings?

As reported by overboost, crowz, and me, these are the original arrays:
0F 62 32 CB 4B CB 73 38 78 6A 7D FF overboost
0F 65 32 D0 4B D0 73 38 78 69 7D FF crowz
0F 5E 32 C9 4B C9 73 36 78 6A 7D FF oldskewel
15 -- 50 -- 75 -- 115 -- 120 -- 125 -- hex to Decimal (*C) conversions. meaningful values shown, others left as "--"

So my question is what do those in-between values do / mean? They are different, but not random or zero, for the three of us. I left mine unchanged, not wanting to risk anything. And I see from your post here that they are shown as "00" in the pre-designed array choice.

Mostly just curious, but I would have felt better about the whole process if I understood everything, like this mystery. I was fairly paranoid about bricking the car while doing that.

BTW, the breakpoints I programmed, and am still happy with, are
15 - 60 - 94 - 96 - 110 - 115

with a few more details in:
https://xoutpost.com/1163393-post54.html

With 94 and 96 as the middle two, it pretty much does away with the deadband region. It operates with the gauge straight up (at 95, I guess) most of the time, but will now clearly move a little hotter or a little cooler when things are a little cool or a little hot.

[Clockwork]

Awesome, thanks very much for this update!!! I've been wanting to do it for a year now.

Sent from my Pixel 3 using Tapatalk

[andrewwynn]

I want to do this so bad don't have the hardware/sw to do it maybe that'll be my birthday present.

I drove for months with a car that rarely if ever got to closed loop only discovered my tstat didn't close when ambient got below about 10c and cabin heat stopped working. What a stupid design. On the hot side basically only indicates that you blew out all your coolant. If there is a pint left won't read red.

[Effduration]

I use NCS Expert more than Dummy.

So, In NCS Expert, we probably just need to change the following in KOMBI module :

KUEHLMITTELTEMP_ADC_WERT: kennline_03

to:

KUEHLMITTELTEMP_ADC_WERT: kennline_04

And then change MOTOR_UEBERTEMP in LCM as noted

[oldskewel]

And hey, I'm now reminded of how that reprogramming may have already avoided a problem ...

Earlier this year, on a rare (for here) 100*F summer day, my daughter was driving the X5, waiting for 20 minutes in the drive through line at In-n-Out Burger (something I would never ever do), with the AC on. Later diagnosis confirmed that my Aux fan had failed. But the first clue was that she luckily noticed the temp gauge very quickly head up to the hot zone. She then immediately turned off the AC and it went back down to normal temp.

So the difference between 125*C (standard setting) and 115*C (my custom setting) may have avoided an overheating problem. At the least, it very quickly pointed to a problem with the aux fan. I'll look to get the UEBERTEMP programmed as well if I ever get my PASoft BMW Scanner software working again (worked easily and perfectly out of the box, and for a few years, then it seems it is now being blocked by a windows update).

Highly recommended modification, for anyone who has not yet done it. I believe there is some risk when manually editing the HEX values. But if it is a simple checkbox selection as @zboost shows, that should reduce the barrier to entry so more people can get it done.