Fault code P011100

[Gordycol]

Can anyone shed any light please on this error code P011100 Air intake temperature sensor1? (2017 2.0 CXGB)
I have reset the management light and it stays off for 3-5 days then its back on again. When the eml is on it still drives absolutely fine with no noticeable difference at all.
I have swapped the sensor twice and double checked all of the respective wiring but it is exactly the same outcome, stays off for a day or 3 then back on again.
Am I barking up the wrong tree here? Photos attached, thank you for any help

 

[DXX]

Unlikely that two sensors fail. Did you compare the electrical resistance of new against the old sensor with a multimeter?
The transporter electrical looms aren’t exactly great quality and there have been cases of damage during maintenance, vibration, chaffing and rodents. Worth a check over.
Has the air filter been maintained correctly?

 

[roadtripper]

Did I read in a recent thread that there are actually 2 MAF sensors - if so maybe it's the other one that's faulting?

 

[roadtripper]

Dreaded glow plug light on

The cars have two MAP sensors, one on top right next to Air flow sensor and one longer down on the engine, its easiest to change from underside of car but its tight. Bosch number on the one I changed is 0281006059. Yes IC is intercooler. The MAP sensor on top is from manufactor KW and have part...

www.t6forum.com

 

[mmi]

Would be useful to know what engine and what model year exactly - engine code is something like CAAC, CXGB, etc.
Per EU6 engine (CX...) wiring diagram the air intake temperature sensor is integrated into air mass meter (the neighbouring connector).

Can you disconnect one plug at a time, turn ignition on and read the fault codes - a disconnect should manifest an immediate fault?

 

[Gordycol]

Would be useful to know what engine and what model year exactly - engine code is something like CAAC, CXGB, etc.
Per EU6 engine (CX...) wiring diagram the air intake temperature sensor is integrated into air mass meter (the neighbouring connector).

Can you disconnect one plug at a time, turn ignition on and read the fault codes - a disconnect should manifest an immediate fault?

Hi mmi, thank you for the reply, yes it says on the first line of my post? - it's a 2017 2.0 CXGB
If I disconnect the suspected sensor (arrowed) it says Air Intake Temperature Sensor - Open Circuit so it definitely points to the same suspected sensor, so with the original one and 2 others it is exactly the same outcome, OK for a day or 3 then back on.

 

[Gordycol]

Unlikely that two sensors fail. Did you compare the electrical resistance of new against the old sensor with a multimeter?
The transporter electrical looms aren’t exactly great quality and there have been cases of damage during maintenance, vibration, chaffing and rodents. Worth a check over.
Has the air filter been maintained correctly?

Thanks for the reply, I have changed the air filter myself with the correct Bosch one, the loom/ respective connectors all look good aswell, it's only done 45k miles so most annoying

 

[Gordycol]

Did I read in a recent thread that there are actually 2 MAF sensors - if so maybe it's the other one that's faulting?

Thanks roadtripper, I didn't know that, I changed the MAF (the main one to the left of it) a while ago, could that be the problem? It wasn't an OE one just one from Euro CPs, could that affect the sensor upstream of it? It drives the same with no faults EM light on or off so no real issues, just an annoying bug!!

 

[Gordycol]

Did I read in a recent thread that there are actually 2 MAF sensors - if so maybe it's the other one that's faulting?

I did disconnect it but the error then came up with the same sensor but now 'Open Circuit' so it looks to be referring to the same sensor but who really knows what goes on inside the ECU??

 

[bluezie]

These sensors are very reliable, so now 2 have been fitted, it's very unlikely to be them.
Try splitting open the conduit, and teasing out the wires. Check for chafes and breaks, especially around the plug, and where the conduit goes into the loom. A lot of breaks are internal, so look for any sharp bends, and floppy insulation. The wires should deform uniformly along their lengths, so any odd floppy kinks will be internal breaks, which easily pull apart.

 

[roadtripper]

I did disconnect it but the error then came up with the same sensor but now 'Open Circuit' so it looks to be referring to the same sensor but who really knows what goes on inside the ECU??

Re-reading the post I linked to they were talking about MAP (pressure) not MAF (flow) sensors.

Given you can show the fault appears with unplugging I'd agree with the suggestions it's more likely to be a cable issue.

 

[oldiebut goodie]

Don't take it as read that wires are intact - I have to keep showing this break in a new Webasto loom ( it took some finding ):

 

[mmi]

If I disconnect the suspected sensor (arrowed) it says Air Intake Temperature Sensor - Open Circuit

Interesting - what's the actual fault code? What's the fault code reader used?

Experiments on engine CXEB (MY18)​

"Arrowed sensor"​

When I disconnect the sensor on mine I get quite a different fault code (by VCDS)

31391 - Manifold / Barometric Pressure Sensor (G71) / (F96)
          P0105 00 [00100011] - Malfunction

With the arrowed sensor disconnected intake temperature reading is still ok but air pressure reading hits it's lower limit. Also plain 5 Volts (sensor reference voltage) indicates open sensor circuit.

EDIT: Well, it seems that the converted pressure value (mbar) might actually be a filtered (damped) value as it doesn't respond immediately. Whereas the raw voltage value responds immediately. Also by taking van up to mountainous area could record pressure values down to 700 mbar.​

IDE00348   Intake air temperature 25  C
IDE07734   Air filter outlet: pressure sensor 1 bank 1: raw value 947 mbar
IDE07735   Air filter outlet: pressure sensor 1 bank 1: uncnd. voltage 4.999 V

Connected again

IDE00348   Intake air temperature 25 °C
IDE07734   Air filter outlet: pressure sensor 1 bank 1: raw value 998 mbar
IDE07735   Air filter outlet: pressure sensor 1 bank 1: uncnd. voltage 4.041 V

---

"The Other" connector (Mass Air Flow Sensor)​

When I disconnect the "other" connector (Mass Air Flow Sensor) I get the following codes and flashing coil light on dash:

13174 - Mass Air Flow Sensor (G70)
          P0103 00 [10100011] - Signal too High
          MIL ON - Not Confirmed - Tested Since Memory Clear
30357 - Intake Air Temp. Sensor (G42)
          P0113 00 [00100011] - Signal too High

Also temperature reading hits it's lower limit - again plain 5 Volts indicates open sensor circuit.

IDE00348   Intake air temperature -40  C
IDE08065   Mass airflow sensor 1 bank 1 temperature sensor: raw value 4.996 V

Connected again

IDE00348   Intake air temperature 25  C
IDE08065   Mass airflow sensor 1 bank 1 temperature sensor: raw value 3.316 V

Alhtough the above are from 2018 CXEB engine the circuitry for these sensors is identical with CXGB MY17 engine per wiring diagrams.

 

[Gordycol]

Interesting - what's the actual fault code? What's the fault code reader used?

Experiments on engine CXEB (MY18)​

"Arrowed sensor"​

View attachment 243532
When I disconnect the sensor on mine I get quite a different fault code (by VCDS)

31391 - Manifold / Barometric Pressure Sensor (G71) / (F96)
          P0105 00 [00100011] - Malfunction

With the arrowed sensor disconnected intake temperature reading is still ok but air pressure reading hits it's lower limit. Also plain 5 Volts (sensor reference voltage) indicates open sensor circuit.

IDE00348   Intake air temperature 25  C
IDE07734   Air filter outlet: pressure sensor 1 bank 1: raw value 947 mbar
IDE07735   Air filter outlet: pressure sensor 1 bank 1: uncnd. voltage 4.999 V

Connected again

IDE00348   Intake air temperature 25 °C
IDE07734   Air filter outlet: pressure sensor 1 bank 1: raw value 998 mbar
IDE07735   Air filter outlet: pressure sensor 1 bank 1: uncnd. voltage 4.041 V

---

"The Other" connector (Mass Air Flow Sensor)​

When I disconnect the "other" connector (Mass Air Flow Sensor) I get the following codes and flashing coil light on dash:

13174 - Mass Air Flow Sensor (G70)
          P0103 00 [10100011] - Signal too High
          MIL ON - Not Confirmed - Tested Since Memory Clear
30357 - Intake Air Temp. Sensor (G42)
          P0113 00 [00100011] - Signal too High

Also temperature reading hits it's lower limit - again plain 5 Volts indicates open sensor circuit.

IDE00348   Intake air temperature -40  C
IDE08065   Mass airflow sensor 1 bank 1 temperature sensor: raw value 4.996 V

Connected again

IDE00348   Intake air temperature 25  C
IDE08065   Mass airflow sensor 1 bank 1 temperature sensor: raw value 3.316 V

Alhtough the above are from 2018 CXEB engine the circuitry for these sensors is identical with CXGB MY17 engine per wiring diagrams.

Ahh thank you for this, that's interesting and good reading. Unfortunately I only have an Icarsoft reader, does most things except digging really deep. I really don't understand the logic of it only showing the fault every 3rd day, that's what I can't get my head around??

 

[roadtripper]

I really don't understand the logic of it only showing the fault every 3rd day, that's what I can't get my head around??

My understanding is that some intermittent faults are tracked but don't actually cause a full fault until they happen "enough" so that you are not constantly having faults due to occasional minor blips.

So in your case it's likely that 3 days of use is enough to cross that threshold - and something like VCDS can give deep detail on what's logged and why.

 

[DXX]

There’s only so much diagnosis that can be done with a fault code reader. Ultimately it will take some practical investigation of wiring, connections and sensor resistance comparisons to eliminate the basic and most probable causes

 

[mmi]

I really don't understand the logic of it only showing the fault every 3rd day, that's what I can't get my head around??

Failure data for "non-critical" faults is accumulated over several driving cycles before they are "confirmed" - thus they seemingly go away for a couple of days after clearing fault registers. Also it depends how the fault code reader is set to dig into fault codes. E.g. VCDS has an aggressive mode scan which reveals everything, on the contrary VW ODIS normally shows only currently active (or very recently) active codes.

Also the faults can actually fade away if not detected anymore - thus fall back to non-showing level. But again, they can't hide e.g. VCDS aggressive scan All the above for engine controllers, a different story with other controllers.

Just to add for my previous post - the disconnect of mass air flow sensor is critical (flashing coil light) only for the mass air flow sensor part. Temperature sensor alone doesn't trigger much immediately - just a pending fault deeper in the memory.

 

[Gordycol]

Failure data for "non-critical" faults is accumulated over several driving cycles before they are "confirmed" - thus they seemingly go away for a couple of days after clearing fault registers. Also it depends how the fault code reader is set to dig into fault codes. E.g. VCDS has an aggressive mode scan which reveals everything, on the contrary VW ODIS normally shows only currently active (or very recently) active codes.

Also the faults can actually fade away if not detected anymore - thus fall back to non-showing level. But again, they can't hide e.g. VCDS aggressive scan All the above for engine controllers, a different story with other controllers.

Just to add for my previous post - the disconnect of mass air flow sensor is critical (flashing coil light) only for the mass air flow sensor part. Temperature sensor alone doesn't trigger much immediately - just a pending fault deeper in the memory.

Ok thank you, very good point taken, the only reason I have a code reader is only for the fact that I am all Mac at home and I understand the VCDS system(s) are all for Windows laptops etc. Do you know is this the case? Only I didn't fancy chugging my Mac down with Parallels but I might have to if needs be, I'd love to get to the bottom of this

 

[n10n]

Ok thank you, very good point taken, the only reason I have a code reader is only for the fact that I am all Mac at home and I understand the VCDS system(s) are all for Windows laptops etc. Do you know is this the case? Only I didn't fancy chugging my Mac down with Parallels but I might have to if needs be, I'd love to get to the bottom of this

Some discussion here: VCDS on a mac

I used to run VCDS successfully on Intel Mac with VMWare Fusion Player (free).

For ARM Macs apparently Parallels is the way (maybe, no personal experience) - there’s some hope for the other solutions though now that Windows ARM is becoming a thing: I finally tried Windows 11 on ARM after four years of unfairly dismissing Qualcomm's misunderstood platform (and I'm obsessed)