c5 temperature reading

mrlogik · Post by **mrlogik** » 10 Jan 2010, 17:15

Hi all my c5 hdi 110 02 thinks its currently around 40c or 105f outside when its around 1c in reality,is the sensor easy to find and change and does the ecu rely on this reading for fuelling information as it could explain my mpg being around the 40mpg mark rather than a little higher?
While im here il drop another question regarding my drivers door window/electric mirror controller console,windows would go down on both sides but not up [well handy eh?]. Passenger side would go up with its door controller only and drivers side up on turning wipers on full speed, until one wet night when drivers side stay down until dismantled door card and placed in a wooden prop!! Im leaning toward replacing the drivers door switches from citroen dealer to hope that clears it up unless someone else can share a similar problem. One last thing for the moderators could the citroen forum have its own subdirectories to make finding car related problems more specific as currently searching is problematic due to getting all types of citroen model show up rather than just the model your looking for.{Not a complaint this is still the best forum}.

Post by **Peter.N.** » 10 Jan 2010, 17:36

In most Citroens the sensor is at the bottom of the n/s mirror. If you are handy with a soldering iron you can change the sensor without taking the door panel off, cut the leads off the old one, shorten them on the new one and solder them together then slide some sleeving over the join.

Simon99 · Post by **Simon99** » 11 Jan 2010, 13:51

Had similar problem with my passenger front window. Would go down with drivers door window control but only up by pressing passenger window switch. Popped out drivers door window control and took it apart and gave it a good clean. Seemed to be gunked up with maybe spilt soft drink (previous owner) and fluff. Works now good as new and was amazed at ease of fix.
Can confirm C5 temp sensor is on under side of passenger wing mirror. You can remove mirror glass by gently prising off with screwdriver from behind. This then gives you access to four (I think) plastic tabs which hold on colour coded main cover. These are bu**ers to remove but if you can get it off should be able to cut wires to temp sensor and remove. You may find it easier to remove whole wing mirror first but this involves first removing door card and inner trim.

Post by **Paul-R** » 11 Jan 2010, 14:17

Does anyone have spec for the just the temp sender?

I know people say they are cheap from the dealers but to me cheap is the 50p or so that just the sender would be from an electronics supplier!

Simon99 · Post by **Simon99** » 11 Jan 2010, 14:25

Pretty sure external temp sensor has no involement in fueling info. Mine was disconnected for some weeks but was on petol C5.

Post by **Peter.N.** » 11 Jan 2010, 14:39

Paul-R wrote:Does anyone have spec for the just the temp sender?

I know people say they are cheap from the dealers but to me cheap is the 50p or so that just the sender would be from an electronics supplier!

Unfortunatly it has to be the correct shape to fit.

wheeler · Post by **wheeler** » 11 Jan 2010, 17:03

Simon99 wrote:Pretty sure external temp sensor has no involement in fueling info. Mine was disconnected for some weeks but was on petol C5.

It has nothing to do with fueling but it can affect the operation of the A/C

Post by **myglaren** » 11 Jan 2010, 17:57

I believe that they are approximately £12 from the dealer.

Post by **Paul-R** » 11 Jan 2010, 21:09

myglaren wrote:I believe that they are approximately £12 from the dealer.

My point exactly!

mrlogik · Post by **mrlogik** » 11 Jan 2010, 21:21

Thanks for the prompt replies guys on both issues ill be prizing glass sometime soon,the c5 was pretty untidy when i got it and i still have the switches for the drivers door so they'l be dismantled and cleaned soon. Im surpsised the c5 doesnt take a temperature reading from somewhere outside for its fuelling though as most modern inject wether petrol or diesel?

wheeler · Post by **wheeler** » 11 Jan 2010, 22:25

It uses the coolant temperature info & the air intake temperature info for fueling.

Post by **Paul-R** » 12 Jan 2010, 09:41

It doesn't use the outside air temperature reading at startup for glow plug operation?

Post by **Peter.N.** » 12 Jan 2010, 10:07

It uses engine temperature I believe.

civvie · Post by **civvie** » 12 Jan 2010, 16:50

A while back when mine was still under warranty I had the same problem of false reading. I took it into the dealer and he said it needs to be changed asap as the ecu uses the reading to run properly. They did it there and then.

Steve

wheeler · Post by **wheeler** » 12 Jan 2010, 20:20

civvie wrote:A while back when mine was still under warranty I had the same problem of false reading. I took it into the dealer and he said it needs to be changed asap as the ecu uses the reading to run properly. They did it there and then.

Steve

Thats complete nonsense they told you.

Paul-R wrote:It doesn't use the outside air temperature reading at startup for glow plug operation?

The glowplug operation is controled depending on engine temperature (which it gets from the coolant temperature sensor).
If you think about it the engine could be at 95 degrees but the outside air temp could still be minus 5, The engine certainly wouldnt need glowplugs on startup then.

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c5 temperature reading

c5 temperature reading

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