Go Back   The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club Forums > The 75 and ZT Owners Club General Forum
Register FAQ Image Gallery Members List Calendar Mark Forums Read
Notices

Reply
 
Thread Tools Display Modes
Old 3rd January 2021, 22:42   #1
gozo ken
Avid contributor
 
R75 SALOON

Join Date: Feb 2013
Location: Lincolnshire
Posts: 226
Thanks: 20
Thanked 57 Times in 44 Posts
Default Fuel Guage fault.

I don't know if this has been mentioned before,but I had noticed my gauge going down sooner than I expected,so I put 50 euros in,then took my friend to the pharmacy,as I was waiting,I noticed the gauge was showing lower than a quarter tank,at first I thought I'd been short changed at the pump,then thought it might be leaking,badly. Then I remembered that the on board diagnostics could tell me how much fuel I have in the tank,sure enough after pressing the trip knob after turning on the ignition,I found it and it read 49.5 litres,.relief! No leak and I'd not been robbed.
Anyway to fix the gauge,all I did was scroll further and did a software reset,,gauge as now worked correctly for 5 days,so job done.
Hope this is useful for someone else.
It must be said that having four 75diesels over 19 years,I've never known this to happen,first time for everything!
Happy new year everyone,
Ken.
gozo ken is offline   Reply With Quote
Old 3rd January 2021, 22:48   #2
Number 6
This is my second home
 
Rover 75 tourer Club CD/Limo Tints

Join Date: Nov 2008
Location: Meneac
Posts: 6,759
Thanks: 5,007
Thanked 1,609 Times in 869 Posts
Default

Quote:
Originally Posted by gozo ken View Post
I don't know if this has been mentioned before,but I had noticed my gauge going down sooner than I expected,so I put 50 euros in,then took my friend to the pharmacy,as I was waiting,I noticed the gauge was showing lower than a quarter tank,at first I thought I'd been short changed at the pump,then thought it might be leaking,badly. Then I remembered that the on board diagnostics could tell me how much fuel I have in the tank,sure enough after pressing the trip knob after turning on the ignition,I found it and it read 49.5 litres,.relief! No leak and I'd not been robbed.
Anyway to fix the gauge,all I did was scroll further and did a software reset,,gauge as now worked correctly for 5 days,so job done.
Hope this is useful for someone else.
It must be said that having four 75diesels over 19 years,I've never known this to happen,first time for everything!
Happy new year everyone,
Ken.
Thanks for that, you do it on the internal diagnostics?? if so which section did you use?
__________________
]

"I started out with nothing, and Ive still got most of it left!"
Number 6 is offline   Reply With Quote
Old 4th January 2021, 17:04   #3
T-Cut
This is my second home
 
Rover75 and Mreg Corsa.

Join Date: Nov 2006
Location: Sumweer onat mote o'dust (Sagin)
Posts: 21,751
Thanks: 341
Thanked 3,660 Times in 2,924 Posts
Default

Quote:
Originally Posted by gozo ken View Post
Anyway to fix the gauge, all I did was scroll further and did a software reset. Gauge has now worked correctly for 5 days, so job done.
Hello Ken, it's amazing that few of us do the obvious thing when our electronic gizmos misbehave. This could be a good example of how a very common, often discussed issue with the fuel gauge might be explained. A software glitch. or mabe there's a bug. Most software has them so why not here? The 'Software Reset' option listed in the Diagnostic Mode has never been examined as far as I know. Certainly not in my time around here. There's likely a fear that it could have dire implications for the whole convoluted system, so nobody has risked pushing that particular button. So, for whatever reason, you did and seemingly fixed the fuel gauge. Congratulations, you may have discovered something new about Diagnostic Mode.

A useful next step would be for others with the wonky fuel gauge syndrome to bite the bullet and push the Reset button. Let's generate some data to support the hypothesis. A simple software bug would certainly be more plausible than the way-out theories I've read over the years.


I trust you've observed no other effects after the reset?


TC

Last edited by T-Cut; 4th January 2021 at 17:06..
T-Cut is offline   Reply With Quote
Old 4th January 2021, 22:55   #4
Sonic ZS
Posted a thing or two
 
Sonic ZS's Avatar
 
75 Conn CDT Tourer, 75 Conn SE V6, 75 Conn V6, 75 Conn CDTi Tourer, ZS 180

Join Date: Jan 2014
Location: Devon
Posts: 1,982
Thanks: 1,287
Thanked 963 Times in 534 Posts
Default

This is very interesting - so you press the trip button up to number '19', then when 'log 1 off' is showing, you click through again to number '21'.

But how do you activate the reset once here ? Does it do it automatically, or is there another sequence of specific button pressing to get it to reset ??

Many thanks
__________________
Sonic ZS is offline   Reply With Quote
Old 5th January 2021, 16:08   #5
gozo ken
Avid contributor
 
R75 SALOON

Join Date: Feb 2013
Location: Lincolnshire
Posts: 226
Thanks: 20
Thanked 57 Times in 44 Posts
Default

Quote:
Originally Posted by Sonic ZS View Post
This is very interesting - so you press the trip button up to number '19', then when 'log 1 off' is showing, you click through again to number '21'.

But how do you activate the reset once here ? Does it do it automatically, or is there another sequence of specific button pressing to get it to reset ??

Many thanks
Yes I just pressed it again,once I reached 21,,everything else seems ok,,although my rain sensor isnt working,but that was before i did this,,,must be as brave when I connect TOAF, to sort that one out..
As I can't pop around to see Big Russ,unless he fancies a holiday in Gozo,Ha Ha,,

Last edited by gozo ken; 5th January 2021 at 16:37..
gozo ken is offline   Reply With Quote
Old 5th January 2021, 16:11   #6
gozo ken
Avid contributor
 
R75 SALOON

Join Date: Feb 2013
Location: Lincolnshire
Posts: 226
Thanks: 20
Thanked 57 Times in 44 Posts
Default

Quote:
Originally Posted by T-Cut View Post
Hello Ken, it's amazing that few of us do the obvious thing when our electronic gizmos misbehave. This could be a good example of how a very common, often discussed issue with the fuel gauge might be explained. A software glitch. or mabe there's a bug. Most software has them so why not here? The 'Software Reset' option listed in the Diagnostic Mode has never been examined as far as I know. Certainly not in my time around here. There's likely a fear that it could have dire implications for the whole convoluted system, so nobody has risked pushing that particular button. So, for whatever reason, you did and seemingly fixed the fuel gauge. Congratulations, you may have discovered something new about Diagnostic Mode.

A useful next step would be for others with the wonky fuel gauge syndrome to bite the bullet and push the Reset button. Let's generate some data to support the hypothesis. A simple software bug would certainly be more plausible than the way-out theories I've read over the years.


I trust you've observed no other effects after the reset?


TC
I still thought it prudent to check diagnostic re- fuel levels in the tank before narrowing it down to something wrong with the gauge.
gozo ken is offline   Reply With Quote
Old 25th December 2021, 22:19   #7
gozo ken
Avid contributor
 
R75 SALOON

Join Date: Feb 2013
Location: Lincolnshire
Posts: 226
Thanks: 20
Thanked 57 Times in 44 Posts
Default

Just a quick update regarding my fuel gauge issue I had last year.
Software reset did the trick with no other issues and guage has worked perfectly since.
This may help the chap who's having a problem at the moment.
gozo ken is offline   Reply With Quote
Old 25th December 2021, 22:28   #8
COLVERT
This is my second home
 
R75 Saloon.

Join Date: Feb 2009
Location: France/or Devon.
Posts: 14,003
Thanks: 3,851
Thanked 2,167 Times in 1,816 Posts
Default

Thanks very much for taking the trouble to come back and tell us of your success story.----
COLVERT is offline   Reply With Quote
Old 26th December 2021, 19:30   #9
T-Cut
This is my second home
 
Rover75 and Mreg Corsa.

Join Date: Nov 2006
Location: Sumweer onat mote o'dust (Sagin)
Posts: 21,751
Thanks: 341
Thanked 3,660 Times in 2,924 Posts
Default

Thanks for the update. It seems apparent from Ken's experience that problems with the fuel gauge may actually be of two kinds, hardware failure and software glitches. It's well known that physical wear in the central area of the float arm rheostats gives rise to readout errors. It seems to me unlikely that the Software Reset in the Trip Screen Diagnostic Routine will fix a worn out winding. So, not all fuel gauge issues are mechanical. This of itself is usefull additional info on how these things tick.


TC
T-Cut is offline   Reply With Quote
Old 29th December 2021, 01:16   #10
Briodyjl01
Gets stuck in
 
Rover 75 Tourer, Rover 75 Saloon

Join Date: May 2018
Location: Castleford
Posts: 959
Thanks: 237
Thanked 185 Times in 113 Posts
Default

Thank you! How do I find the guide to do the diognostic as I forgot where it is?
__________________
Too many Rovers to count ……
Briodyjl01 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT. The time now is 06:21.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright © 2006-2023, The Rover 75 & MG ZT Owners Club Ltd