Audi A4 B9 1.4 overheating P011700 Engine Coolant temperature sensor 1 circuit low

[Paul1973]

Hi everyone, hope all are well after the virus and lockdown.
So, I was driving my 2018 Audi A4 1.4 tfsi and my Aircon was ice cold when the car is moving but then blowing hot when stationary.
Strange I thought, then when stationary (stuck) in traffic the engine temp gauge rised right to the top, like HOT! And dreaded steam coming from the engine bay! I pulled over let her cool off and then I scanned fvag and got these codes:
P011700 Engine Coolant temperature sensor 1 circuit low.

And another:
P191B00 coolant fan control module implausible signal.
I'm hoping someone has had this issue and could kindly shed some light?
Any help is greatly appreciated.

 

[Paul1973]

PS I've hunted high and low on here and, worryingly found nothing? So please help?

 

[DyslexicDog]

P191B00 coolant fan control module implausible signal suggests an issue with the cooling fan module.

Reading this https://forums.ross-tech.com/index.php?threads/1492/#post-13004 might help you check your fan is operational and functioning as expected. Of course, this is a 2004 so some things may have changed but as you've mentioned, GoogleFu is not yielding too many results.

P011700 Engine Coolant temperature sensor 1 circuit low

Reading here suggests that your sensor may have fried for a number of reasons - https://www.troublecodes.net/pcodes/p0117/

• Defective ECT sensor
• Short to ground on ECT signal circuit
• Faulty or damaged connectors
• Wiring harness damaged Loose terminals at ECT or PCM
• Overheated engine
• Defective ECM/PCM (not likely)

I'd start with checking your coolant level, for leaks and think back to whether you ever heard your fan going during the steam out the bonnet event.

If you have VCDS you can post up an autoscan and see if there is any freeze frame data available.

 

[Paul1973]

Thanks Dog for your reply. When the car overheated I noticed that the fan was definitely not running. After letting the car cool down and refilling the coolant reservoir with around 1 litre, I then beated a hasty retreat home.
The next day I scanned with FVAG and found the aforementioned codes. I cleared the codes and then went for short 5 mile drive, returned home and left it running for around 25 mins so well up to temp and still no fan kicking into life at any point?
I've found these parts on flebay and wondered if I'm looking at the right parts:

 

[Paul1973]

Thanks Dog for your reply. When the car overheated I noticed that the fan was definitely not running. After letting the car cool down and refilling the coolant reservoir with around 1 litre, I then beated a hasty retreat home.
The next day I scanned with FVAG and found the aforementioned codes. I cleared the codes and then went for short 5 mile drive, returned home and left it running for around 25 mins so well up to temp and still no fan kicking into life at any point?
I've found these parts on flebay and wondered if I'm looking at the right parts:

The last part has a part number starting 8K so probably not suitable but a similar type part maybe?
I'm going to have a dig around under the bonnet and see if there's any loose/damaged wires to the fan module but not sure if it's something that I can check from above?

 

[DyslexicDog]

Thanks Dog for your reply. When the car overheated I noticed that the fan was definitely not running. After letting the car cool down and refilling the coolant reservoir with around 1 litre, I then beated a hasty retreat home.
The next day I scanned with FVAG and found the aforementioned codes. I cleared the codes and then went for short 5 mile drive, returned home and left it running for around 25 mins so well up to temp and still no fan kicking into life at any point?
I've found these parts on flebay and wondered if I'm looking at the right parts:

The fan won't necessarily kick in by just idling, especially on a mild day. I would suggest using VCDS where you can do an output test as suggested (https://www.ross-tech.com/vcds/tour/out_test.php).

1L of coolant missing doesn't sound too dramatic but I'm not sure without checking ETKA how much you need. Did the error codes come back after your drive? Honestly though, after getting steam out your bonnet, I'd be investigating before driving anywhere other than a dealership/garage.

The order of investigation for me would be:

1. Check for coolant leaks or discolouration to indicate head gasket issues
2. Check header tank cap/replace
3. Output test/diagnositic testing (might lead to replacing fan control module depending on result)
4. Replace coolant temp sensor
5. Replace thermostat

I'm not an expert so the above is only how I'd tackle the problem. If you share your VIN (PM or otherwise) I can try to look up some part numbers for you.

 

[DyslexicDog]

The last part has a part number starting 8K so probably not suitable but a similar type part maybe?
I'm going to have a dig around under the bonnet and see if there's any loose/damaged wires to the fan module but not sure if it's something that I can check from above?

Honestly, get yourself erWIN manuals https://erwin.audi.com/erwin/showHome.do if you're going to start poking about.

Pay 7 euro for an hour and download them all for use.

These are almost better than the Haynes manuals, which seem non-existant (or actually cease to exist) for the B9.

 

[DyslexicDog]

Any updates?