False temperature reading

Hi all,
I don't really post on this forum but use it as source of useful information for my HP4 track bike. That being said I have an issue that we're struggling to get to the bottom of.

Whilst racing at the end of last year, I took a heavy fall and it's been a bit of slow financially controlled rebuild. Pretty done most of it myself apart from some final issues I have had which have been resolved by the garage I use.
The bike is now complete apart from 1 final fault. The water temperature reading never raises above 40/50 despite the bike being run for a time where it should be 90/100.
The sensor has been replaced which has made no difference. When I first got the bike the fans were disconnected and they have only been reconnected during the rebuild (not tried disconnecting them again).
The bike has had a new instrument cluster as part of the rebuild which appears to be working fine.
It was on the dyno yesterday afternoon and was reading a constant 187, which maybe a bit low because we assume the bike is compensating for the apparent low temperature.
The bike is currently still at the garage and I'm after any feedback r advice I can take to them early next week as the frustration of not being able to get on track has reached boiling point!

Although I'm desperate to get the bike out again I would prefer to get this issue sorted.

Cheers

John

Is that 187 F or a typo

apologies 187 bhp on dyno

Morning chaps, as I know everyone will be busy eating easter eggs whilst they skim through this forum, thought I'd post a picture to help with potential fault finding.

When I got my track bike the temp wasn't reading right and sometimes went into the minus. It has a separate temp unit fitted.
Since BMW done an update the ddc code is showing in it's place and I read when the ddc suspension is disconnected like mine it affects the temperature reading.
No help I know but would be interested in any info.

Sent from ma phone Galaxy S7

BrucieB said:

When I got my track bike the temp wasn't reading right and sometimes went into the minus. It has a separate temp unit fitted.
Since BMW done an update the ddc code is showing in it's place and I read when the ddc suspension is disconnected like mine it affects the temperature reading.
No help I know but would be interested in any info.

Sent from ma phone Galaxy S7

Click to expand...

But it still runs ok on track? I'm guessing ,mine is ok to run but just missing that security of knowing the true temp.

Does the clocks need coding to the bike?

Jay1000rr said:

Does the clocks need coding to the bike?

Click to expand...

no all that has been done thanks buddy.

I've had mine on track twice now and all good power wise

Sent from ma phone Galaxy S7

Has the bike been plugged in? I'd get it up to temp and see if the computer reads the correct temp or the same as the clock displays. Then you may be looking at an ecu fault or (less likely) a break in the loom causing high resistance

Hi Stephen, yes it has been hooked up to the computer, not sure if it was different readings but I will check tomorrow. It's the only remaining fault so hopefully not an eco issue, although if it is can these be repaired?

Just managed some time at the garage. When the bike ignition is turned on, the temperature is reading MINUS 78, when it is run up for a little while it never goes above + 50c, doesn't seem to be a problem with thermostat. As I mentioned earlier this is a replacement sensor and the previous one was having the same readings.

Any thoughts?

John

Westdale said:

Just managed some time at the garage. When the bike ignition is turned on, the temperature is reading MINUS 78, when it is run up for a little while it never goes above + 50c, doesn't seem to be a problem with thermostat. As I mentioned earlier this is a replacement sensor and the previous one was having the same readings.

Any thoughts?

John

Click to expand...

So do you know if the diagnostic machine reads the same or correct temp?

I would probably test the resistance at the sensor then test it again through the loom at the ecu end and see if there's a significant difference, it should be the same. Then I'd be starting to think ecu or clocks but more likely ecu as the clocks should just be showing what the ecu tells them...

Interesting fault.

Didn't get chance to test on the diagnostic machine today, hopefully tomorrow. Assuming the resistance is the same does that mean there is a fault with the ecu? (brand new clocks and everything else is working on the displays as it should). Also if there is a fault with the ecu, is it fixable, involved, expensive?

Interesting fault which has stopped me from getting on the track, frustrated is not the word.

Cheers for help, it is appreciated.

Westdale said:

Didn't get chance to test on the diagnostic machine today, hopefully tomorrow. Assuming the resistance is the same does that mean there is a fault with the ecu? (brand new clocks and everything else is working on the displays as it should). Also if there is a fault with the ecu, is it fixable, involved, expensive?

Interesting fault which has stopped me from getting on the track, frustrated is not the word.

Cheers for help, it is appreciated.

Click to expand...

I couldn't be certain, but it would rule out the loom.

Are the old clocks completely ruined?

And I've no idea about the ecu being reparable, I've never had to replace one.

Stephen said:

I couldn't be certain, but it would rule out the loom.

Are the old clocks completely ruined?

And I've no idea about the ecu being reparable, I've never had to replace one.

Click to expand...

yes clocks were a right off. I will try and get those tests done tomorrow so at least I can move forward.

The garage was able to to access the ecu through the diagnostic software which had not been available last week. Interesting results.


Further update (if anybody is left wondering)!!

Upon starting the bike the ecu is telling the diagnostics that it is 15c however the dash shows -40. After the bike is run up to temp, around 90c (on the diagnostics) it displays 60c on the dash. At 101 the fans cut in and successfully bring the temp down, at this point the dash and diagnostics read 99c!!??


The garage is happy the bike is running fine and the cooling system is working ok despite showing incorrect details initially on the dash. The question is if I'm happy to accept it as it is, or spend more time and money (lost racing) further sorting the fault.
I'm leaning towards getting the bike on track and seeing how it runs.

Westdale said:

The garage was able to to access the ecu through the diagnostic software which had not been available last week. Interesting results.


Further update (if anybody is left wondering)!!

Upon starting the bike the ecu is telling the diagnostics that it is 15c however the dash shows -40. After the bike is run up to temp, around 90c (on the diagnostics) it displays 60c on the dash. At 101 the fans cut in and successfully bring the temp down, at this point the dash and diagnostics read 99c!!??


The garage is happy the bike is running fine and the cooling system is working ok despite showing incorrect details initially on the dash. The question is if I'm happy to accept it as it is, or spend more time and money (lost racing) further sorting the fault.
I'm leaning towards getting the bike on track and seeing how it runs.

Click to expand...

As long as the fan kicks in that's the most important I guess.. although if it's reading low you won't know if it's overheating...

Well the ecu is reading the correct temp and cutting the fans in, I'd obviously prefer to get it all working...

Just a stab, ecu has been checked to be reading correct and the fan is triggered as should be, you have new clocks, is it not feasible the fault is with the clocks?
Any chance to plug another clock in?