C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

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wil996
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C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by wil996 »

Hi All,
This one has got me stumped??
C5 estate mk II 2004, 2.0 HDI 136hp
I have had this car 3 months, it's only done 80,000miles and is in great condition.
I changed all filters when I bought it, as there was little history.
The engine light is on, with depollution system faulty on display.
I've managed to hook up my pc with basic reader, which gives the following faults

P0098 Intake Air Temp Sensor 2 circuit high
P1598 Manufacturer controlled code (unknown)
P1351 IDM input circuit malfunction/Ignition coil control circuit high voltage. Or SID 803/EDC16C3 - Pre/P
P1434 A/C Refrigerant temperature circuit High

I cannot find any info on-line?

Can anyone point me in the right direction? Where does the sensor 2 reside?

Thanks in advance for any help and apologies if I've done this incorrectly, first time posting :-D
Cheers
Wil

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GiveMeABreak
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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by GiveMeABreak »

Hi and welcome, post your VIN up so I can confirm the vehicle type - but I suspect you have the DW10BTED4 138 engine.

P0098: Intake air temperature signal - Open circuit or short circuit to the plus. This means the voltage of the signal from the inlet air temperature sensor is higher than 4.95 V, corresponding to a temperature of -29°C for 5 seconds.

The fault is activated when the air temperature at the flow meter is higher.

Whilst active, the following down grade modes are in effect: Suppression of the principal, pilot and post-injection flow corrections and the engine management lamp will be switched on.

Symptoms as a result: Slightly higher fuel consumption and / or Smoke from the exhaust.

Suspect areas: Turbocharged air temperature sensor, Electrical harness.

The P1351 fault is common on HDis - its referring to the glow plug relay. Most HDis have this fault - so ignore it for the present.

P1434: Well your code reader got that one way off..... nothing to do with the A/C system!

P1434 means the Particle Filter Additive system has excessive temperature or open circuit.
This is the important one - as whilst this fault is active, the engine management system will deactivate the particle emission filter additive pump and also stop the cumulative calculation of the quantity of additive to be injected.

This means that is will stop the additive pump from injecting additive into the fuel tank. This ultimately will prevent assisted regeneration and will lead to clogging of the particle filter - especially on shorter journeys where passive regeneration would normally take place (i.e. on a long journey where the exhaust can reach about 550°C.

The suspect here is the additive pump itself.

Once you pop your VIN up (automatically masked on submission from public view) I can confirm the parts and get a diagram up.

wil996
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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by wil996 »

Hi Marc,
Thanks for your rapid response.
I wish my reader was correct, I'd rather have duff aircon, than DPF issues, haha
My vin is VF7**************[VIN obfuscated, can be read by forum staff]
Is the temperature sensor built into the mass air flow meter?
Can I just swap out the pump?
Thanks again
Wil

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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by RichardW »

ENGINE DIESEL TURBO DW10BTED4 FAP

The intake air temperature sensor looks like its on the air doseur valve (Item 15)
tempsensor.JPG
But there is also another temp sensor (13) - not obvious where this is. Both are around £50 from Citroen - not really cheap enough to change on a whim... you really need some live data to see what the ECU can see which will help point at the right problem.

wil996
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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by wil996 »

I've just found the sensor, it is coked up with black tar like gloop!!! I've measured across the two pins and it's open circuit???? I assume I should get some resistance?

wil996
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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by wil996 »

If I take the dpf pump out, is there any way of testing it?
And can I just replace the pump, or does it have to be programmed to car?
cheers

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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by RichardW »

Don't worry about any pump, if the temp sensor is open circuit and gunked up, replace it and see where it takes you. 13 quid on ebay

wil996
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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by wil996 »

Thanks Richard, one's on order, fingers crossed.

wil996
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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by wil996 »

Thanks to all for your help, a perfect diagnosis. I fitted it on Saturday and the engine light is off (touch wood)!!!

wil996
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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by wil996 »

Damn, I wish I hadn't plugged the reader in.
I still have the P1434 dpf pump issue. If I take the dpf pump out, is there any way of testing it? Is there a fuse for it?
And can I just replace the pump, or does it have to be programmed to car?
cheers

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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by RichardW »

Is the EML still on? If you clear the fault does it come back? Can you read live data with the scanner? If so, what does it say about the DPF soot load and regen frequency?

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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by RichardW »

Hmm looks like the pump is not available separately, only comes with the tank at a cost of £310 :shock: Part No 1500AR - you should be able to get a second hand one - but I'd want to be really sure it was faulty before I went about replacing it! It shouldn't need coding, but there is probably a priming procedure that you should do.

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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by GiveMeABreak »

As for your P1434 Error:

Description of the fault code: Particle filter additive system: Excessive temperature or open circuit. The circuit is open for 1 second.

Conditions for fault activation: When the pump is trying to be activated, and the battery voltage is more than 7V and there is no error on BUS internal to the engine management ECU.

Down-grade modes if fault present: Deactivation of the particle emission filter additive pump, stopping of the cumulative calculation of the quantity of additive to be injected and switching on of the warning lamp and/or warning message.

Suspect areas: Additive pump

Consider the following:

The additive pipe may be blocked or there could be an internal issue, or an electrical short.

Do you know when the last time the additive fluid was topped up? If it has been topped up, was the additive ECU also reset to zero? There is no physical measuring system used in the additive pump system. The additive fluid remaining is estimated and is calculated from original amount in the tank against mileage travelled and the amount injected. There is one possibility I can think of and that is if the additive counter has been reset without the additive tank being topped up, then the system will think there is adequate fluid when the tank could be near empty. This could lead to problems with the pump possibly overheating. This scenario would soon lead to filter clogging and a warning would ensue on the dashboard warning about risk of clogging. It's just a theory. But these are the checking procedures to phsically measure the level:

In order to physically check the level, you would have to remove the additive reservoir and check the amount of fluid recovered from the tank. The following should be the quantities based on mileage for the DW10BTED4 engine:
Distance Travelled MilesDistance Travelled KMQuantity of additive taken from the tank in litres
KilometresMilesDW10BTED4
002,9 + 0,2
30 00018 7502,25 + 0,2
60 00037 5001,6 + 0,2
90 00056 2500,95 + 0,2
120 00075 0000,3 + 0,2
Once reassembled you would need to use Lexia to Perform the actuator test "filling of tube: additive pump - additive injector" to prime the circuit.

To check the circuit itself (whether the additive pump is being controlled or not):

You'll need a plug kit and a vacuum pump with the right adapters:
C5 Add A.PNG
C5 Add A.PNG (89.72 KiB) Viewed 72 times
C5 Add B.PNG
C5 Add B.PNG (75.72 KiB) Viewed 72 times
Manual vacuum pump DA16 with adaptorsPlug Kit
Fuel Additive Circuit
C5 Add C.PNG
(1) Additive injector (Fuel pump gauge module ).
(2) Anti-return valve (According to equipment).
(3) Additive supply pipe.
(4) Additive pump (Additive tank).
Note: Some vehicles are not fitted with a non-return valve from the additive injector. The additive injector fitted with a non-return valve should open at a pressure lower than 400 mbars (According to equipment).

Additive Pump Audible Test

Using Lexia, carry out the "actuating the additive pump" actuator test. This is an audible test to ensure that the additive pump is controlled.
CheckNoise and sensation of vibration when the additive pump is operatingNo noise or sensation of vibration when the additive pump is operating
FindingThe additive pump is controlledThe additive pump is faulty or the power supply is cut
ActionContinue the checkingRepair the additive pump or restore the power supply
Continue the checking
Checking the additive circuit, the additive supply pipe and the additive injector

For all work on the additive circuit, wear safety goggles and hydrocarbon resistant gloves.
C5 Add D.PNG
Visually check the condition of the additive supply pipe (3), looking for traces of additive leaks. Replace the additive supply pipe (3) if necessary.
  • Plug the additive pump using tool the plug kit [0188-T].
  • Connect the tool [01101] to the additive supply pipe (3) (Additive tank end) using a click-on pipe that guarantees the assembly is leak free.
  • Activate, using pressure, the manual pump [01101].
CheckPressure lower than or equal to 400 mbarsPressure higher than 400 mbars
ObservationThe additive injector and the additive supply pipe are not blockedThe additive injector is jammed
or
The additive supply tube is blocked
ActionCondition correct
End of check
Condition not correct
Continue the checking
Repriming the additive supply tube

CAUTION: In all cases, always fill the additive supplied pipe (3).

Remove tools [01101] and [0188-T].
Couple the additive supply tube (3) to the fuel pump gauge module (5) and to the additive pump (4).
Carry out the actuator test "filling of the pipe: additive pump - additive injector" (According to specification) using a Lexia.

wil996
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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by wil996 »

Wow, that's alot of info.
The eml is off. the code comes back after being erased. My reader is very,very basic. I am unable to read soot levels.
I will take the tank off at the weekend to see if there is any visual issues and to check amount of fluid.
I don't know if it's been topped up, it's done 83,000 miles.
Has anyone measured across the pins on the connector on the fluid tank? assuming two of the four pins power the pump?? (looking at a picture of a 1500AR tank)
Would any of these £100 ebay lexias give me soot levels?
Cheers

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GiveMeABreak
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Re: C5 Mk II P0098 Intake Air Temp Sensor 2 circuit high

Post by GiveMeABreak »

Lexia will provide soot level %. But do make sure you get a decent Revision 'C' kit circa £100 mark.

Many members including myself have bough kits from here - where there is a 15% discount - other suppliers are available....

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