2011 C4 Grand Picasso A/C sensors

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venbo_
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2011 C4 Grand Picasso A/C sensors

Post by venbo_ »

Hi guys,

I really need some help and advice. My C4 Grand Picasso's A/C diagnostics says: 1. Driver's side blown air temperature : 658°C , 2.Passengers side blown air temperature: 658°C, 3 Carbon monoxide (CO) concentration/air quality sensor value : 6236, Concentration of nitrogen oxide: 6236... Do you know where these sensors are located? The only sensor I found inside the A/C big blower body is a temp sensor that works well as it shows the correct value (located driver's side down bottom). The weird point is that they call this sensor "Air quality sensor" which is strange as that sensor is just a simple thermo couple (simple temp sensor). I can't find any other sensors looking over diagrams? Any advice and information is highly appreciated. Thanks in advance.
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GiveMeABreak
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Re: 2011 C4 Grand Picasso A/C sensors

Post by GiveMeABreak »

The temperature sensors on the first generation of Picassos are located in the air piping at feet level:
c4 temp sensors.PNG
(111) The temperature sensor of the air entering the passenger compartment from the driver's side.
(112) Passenger air temperature sensor.
venbo_
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Re: 2011 C4 Grand Picasso A/C sensors

Post by venbo_ »

GiveMeABreak wrote:
07 Jul 2021, 00:03
The temperature sensors on the first generation of Picassos are located in the air piping at feet level:

Image

(111) The temperature sensor of the air entering the passenger compartment from the driver's side.
(112) Passenger air temperature sensor.
Thank you very much for your help! Will check them sensors and will get back here. Cheers.
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Re: 2011 C4 Grand Picasso A/C sensors

Post by venbo_ »

Hello there,
I looked for the sensors but looks like my car doesn't have them on the places shown... I have looked exactly on these locations, but I have only a 90 degrees angle white plastic vents with no sensors on them... Probably my Picasso configuration is different? Cheers.
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Re: 2011 C4 Grand Picasso A/C sensors

Post by GiveMeABreak »

Very possible as there are various options on these with various climate ‘zones’ , and additional heating / blower units for these. Best to pop your VIN up so I can see exactly which system and option you have.
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Re: 2011 C4 Grand Picasso A/C sensors

Post by venbo_ »

GiveMeABreak wrote:
09 Jul 2021, 08:16
Very possible as there are various options on these with various climate ‘zones’ , and additional heating / blower units for these. Best to pop your VIN up so I can see exactly which system and option you have.
Thank you very much for your time and attention! Here's the VIN: VF7**************[VIN obfuscated, can be read by forum staff]
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Re: 2011 C4 Grand Picasso A/C sensors

Post by GiveMeABreak »

I’ll have a look as soon as I can as I’m out at present.
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Re: 2011 C4 Grand Picasso A/C sensors

Post by GiveMeABreak »

Perhaps you can explain what the particular problem is with your vehicle to save some time?
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Re: 2011 C4 Grand Picasso A/C sensors

Post by venbo_ »

When the A/C is on - it blows cold only when the fan is at max ( a/c compressors switches on only then). The fan works perfectly at any level position. The a/c is fully serviced (filled, filters, etc..) When diagnosed with Lexia/DiagBox says- driver's and passenger's blown air temperature - above 6K degrees, and the air quality above 6k...
sensors.JPG
When decrease the fan level with just one click - the A/C stops working - that's the problem. So I assume a sensors needs replacing, but can't find them. Thank you.
Last edited by myglaren on 11 Jul 2021, 09:14, edited 1 time in total.
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Re: 2011 C4 Grand Picasso A/C sensors

Post by GiveMeABreak »

So to clarify:

The A/C only works when the fan is on full speed.
The fan works on any speed for hot or warm air or cool air, but not for cold air?

So you should have climate control. What happens when you leave the system on AUTO and set the temperature to say 14. Does the fan speed increase and the temperature change, or does the fan not work and secondly does the temperature start to decrease?
As above, but when you turn the temperature up to say 28, does the fan speed and temperature increase?

What is the outside temperature reading displayed on the multifunction display? The temperature inside the wing mirror affects the A/C system - if that is reading incorrectly it will impact on the system.

As you have Diagbox, have you run the Global Test and are there any fault codes returned?
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Re: 2011 C4 Grand Picasso A/C sensors

Post by GiveMeABreak »

I've just had another look and have you disconnected the battery recently? If so these are complex systems and it is stated:

"MANDATORY: After disconnecting the battery, move for 5 minutes in automatic mode with a set temperature of 21 ° C on the left / 21 ° C on the right to ensure normal system synchronization."

There's little I can do to help on the systems in these vehicles with the multiple configurations available, they are so complicated and the systems change from one model to the other with multiple versions according to number of cooling zones which makes it extra hard.

The systems also can take time to reinitialise (they even talk about parking it in a garage out of the sun for 5 hours to reset the memorised settings!)

I think you may be better off getting it to a dealer and let them work it out - they may know instantly what the issue is.
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Re: 2011 C4 Grand Picasso A/C sensors

Post by venbo_ »

GiveMeABreak wrote:
11 Jul 2021, 09:55
So to clarify:

The A/C only works when the fan is on full speed.
The fan works on any speed for hot or warm air or cool air, but not for cold air?

So you should have climate control. What happens when you leave the system on AUTO and set the temperature to say 14. Does the fan speed increase and the temperature change, or does the fan not work and secondly does the temperature start to decrease?
As above, but when you turn the temperature up to say 28, does the fan speed and temperature increase?

What is the outside temperature reading displayed on the multifunction display? The temperature inside the wing mirror affects the A/C system - if that is reading incorrectly it will impact on the system.

As you have Diagbox, have you run the Global Test and are there any fault codes returned?
The fan always works properly- it works when a/c is switched on, but A/C blows cold only when the fan is on full speed- if I decrease it the A/C stops to blow cold ( the A/C compressor stops). Tried with Auto mode- works with same behavior- depending on the fan speed- it blows cold or not- when set on low temp (14 deg) the fan is on max and blows cold once the internal temp is reached and the fan speed decreased automatically- cold air stops (otherwise as described above the fan is working perfectly on all speeds). The outside temperature is correct- both the display shown and the diagnosed readings. Everything is ok except the reading of the driver's and passenger's blown air temp- if the readings are out of range the cold air will come only on min. temp (14) and max fan speed which is absolutely logical for me. The important is why I can't locate them sensors, are they exists on my Picasso system. Thank you
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Re: 2011 C4 Grand Picasso A/C sensors

Post by venbo_ »

GiveMeABreak wrote:
09 Jul 2021, 10:26
I’ll have a look as soon as I can as I’m out at present.
Hello,

Is it can you check my VIN number when its possible please? Thank you.
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Re: 2011 C4 Grand Picasso A/C sensors

Post by GiveMeABreak »

Unfortunately it doesn't help me determine whether you have the same sensors as the other member's system. :(

AIR CONDITIONING: WITH AUTO RECIRCULATION HEATER MATRIX
ADDITIONAL HEATING: AUTOMATIC ADDITIONAL HEATING
ADDITIONAL AIR CONDITIONING: WITHOUT ADDITIONAL AIR CONDITIONING
REFRIGERATION: AUTOMATIC AIR CONDITIONING
SUPPLEMENTARY HEATER: WITHOUT ADDITIONAL HEATING