Temperature gauge.

[Graham n Karen]

Good morning all.
The temperature gauge on our 2006 Ducato goes straight to N as soon as ignition is turned on, even without engine running. I read somewhere, that this was a common fault so I'm not too concerned, just a little annoyed. On a n other forum I read that if I disconnected the negative battery terminal and turned the ignition on this will get rid of any residual current, then re-connect the battery this sometimes works. Any other funsters had this issue before I go searching? Currently in Roses in Spain so I don't have my multi meter etc with me.
Cheers in advance.

 

[Googlebot]

You can try the battery trick but the sensor is probably knackered.

Not normally a big job, not sure on that model where it is though.

 

[Mike800966]

What do you mean "it goes to n"? Our 2005 only has numbers on it and the pointer sits just below half scale normally.
if it goes to one end of the scale straight away it could be a poor connection to the sensor which will likely be in the waterway around the thermostat housing.
SInce you are away then just stop after a while and just check that the radiator hoses feel normal temp. Dont risk a severe boil up or you could be in for a head gasket.
Mike

 

[Odd job]

Most modern vehicles have the temperature gauge damped to such a degree that they only show overheating when it's far too hot to be of much use. When I had a bongo, with an aluminium cylinder head, that couldn't take overheating, I fitted an after market temperature gauge and it showed the temperature going up and down all the time dependent on the load.

 

[Graham n Karen]

N for no

What do you mean "it goes to n"? Our 2005 only has numbers on it and the pointer sits just below half scale normally.
if it goes to one end of the scale straight away it could be a poor connection to the sensor which will likely be in the waterway around the thermostat housing.
SInce you are away then just stop after a while and just check that the radiator hoses feel normal temp. Dont risk a severe boil up or you could be in for a head gasket.
Mike

N for Normal. 1/2 way up.

What do you mean "it goes to n"? Our 2005 only has numbers on it and the pointer sits just below half scale normally.
if it goes to one end of the scale straight away it could be a poor connection to the sensor which will likely be in the waterway around the thermostat housing.
SInce you are away then just stop after a while and just check that the radiator hoses feel normal temp. Dont risk a severe boil up or you could be in for a head gasket.
Mike

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[Guigsy]

Most modern vehicles have the temperature gauge damped to such a degree that they only show overheating when it's far too hot to be of much use. When I had a bongo, with an aluminium cylinder head, that couldn't take overheating, I fitted an after market temperature gauge and it showed the temperature going up and down all the time dependent on the load.

Some modern vehicles are even worse than that. The movement of the needle is entirely artificial. It follows a predetermined ramp up of readings to Normal. And then remains absolutely static. The only time it moves is if the engine is outside the temperature the ECU expects. So it's effectively an idiot light, dressed up to pretend it's a gauge.

 

[the1andonly]

Bongos were/are very suseptable to over heating but sensible temperature monitoring counteracts that problem. I used an arduino and temperature sensors. Newer vehicles have a more modern solution, OBD2 temperature measurments and an Ap eg Torquepro gives a good implementation. An droid phone can even graph the temperature to assess issues. On my Bongo implementation i could even predict a stuck thermostat, But torque is a sensible solution for periodic checks.

 

[Googlebot]

Some modern vehicles are even worse than that. The movement of the needle is entirely artificial. It follows a predetermined ramp up of readings to Normal. And then remains absolutely static. The only time it moves is if the engine is outside the temperature the ECU expects. So it's effectively an idiot light, dressed up to pretend it's a gauge.

That is astonishing.

Thinking about it, I had a Citroen C5 once with an oil temp gauge. That went up and down but the coolant one didn’t move. Now I know why.

 

[Figaro]

That is astonishing.

Thinking about it, I had a Citroen C5 once with an oil temp gauge. That went up and down but the coolant one didn’t move. Now I know why.

I remember a story from the days when cars had an oil pressure gauge.
It was usual for oil pressure to drop dramatically in a hot engine on idle. Mercedes Benz decided this was off-putting to customers so rigged theirs to only indicate the expected pressure all the time the engine was running, so again an idiot gauge serving no purpose.
I believe they were fined for this but might be wrong.
In fact I'm not sure where I heard the story, it might have been one of my dads tales, probably repeated from his weekly edition of Autocar ?

 

[Mike800966]

Apparently according to the fiat forum, there are two sensors . One for the ecu to drive the fans and the other for the guage. The guage one is down below the main air hose and has a 2 pin plug and probably a blue colour body.
Might be worth a wriggle!. The sensor is about £30
Enjoy the trip
Mike

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[Graham n Karen]

Apparently according to the fiat forum, there are two sensors . One for the ecu to drive the fans and the other for the guage. The guage one is down below the main air hose and has a 2 pin plug and probably a blue colour body.
Might be worth a wriggle!. The sensor is about £30
Enjoy the trip
Mike

It may have come loose when I had a burst hose replaced in Malaga. Will have a look when we stop in Milau later today. Cheers.

 

[Sleeveless]

I remember a story from the days when cars had an oil pressure gauge.
It was usual for oil pressure to drop dramatically in a hot engine on idle. Mercedes Benz decided this was off-putting to customers so rigged theirs to only indicate the expected pressure all the time the engine was running, so again an idiot gauge serving no purpose.
I believe they were fined for this but might be wrong.
In fact I'm not sure where I heard the story, it might have been one of my dads tales, probably repeated from his weekly edition of Autocar ?

Having worked for Mercedes-Benz on the tech side for over 40 years , I'm aware of the oil pressure gauge reading lower at idle with a warm engine , (especially with the intro of less viscous synthetic oils) , this didn't cause any problems, but I have absolutely no recollection of any "rigged" gauges as described. The only situation vaguely similar to this, was on the introduction of the outside air temperature indicator, which used a Hall effect sensor fitted to the speedo, to freeze the reading when the vehicle was stationary.

 

[Figaro]

Having worked for Mercedes-Benz on the tech side for over 40 years , I'm aware of the oil pressure gauge reading lower at idle with a warm engine , (especially with the intro of less viscous synthetic oils) , this didn't cause any problems, but I have absolutely no recollection of any "rigged" gauges as described. The only situation vaguely similar to this was on the introduction of the outside air temperature indicator, which used a Hall effect sensor fitted to the speedo to freeze the reading when the vehicle was stationary.

Probably one of my dads tales then