Another puzzle to solve…

[T6_FunBus]

Seems like my T6 loves my attention recently.

2 years trouble free and the past month its been a pain in the ass!

I had an EML come on this week.

Had a look and have the following:






Assume these three are not a coincidence and are related.

Reference voltage error, heat pump error, adblue heater error.

I can clear and they come back, after two ignition cycles EML back on.

I guess I’ll check the heater support pump issue first, seeing as thats shorting and could be causing other errors? Ia anyone familiar with the pump connector and fuse location?

Other ideas welcomed

Thanks.

 

[T6_FunBus]

Appears there are several pumps as per this thread:

Continued water circulation pumps running - Flat Battery (Resolved)

https://www.t6forum.com/threads/vw-vag-ssp-self-study-programs.11179/

www.t6forum.com

And this one:

Auxiliary Coolant Pump Failure

Engine management light on again, Back at dealers again, No courtesy vehicle again, Missed deliveries and pissed off customers again. Apparently the 2nd auxiliary coolant pump has failed. Moral of the story? If you don't want to be a VW R&D guinea pig, wait at least two years before buying a...

www.t6forum.com

Located heater support pump in 01, I’m busy at the mo, but will pop out later and check this pump and other pumps by running output tests and see what happens.

 

[T6_FunBus]

Heater support pump and adblue heaters seem to activate?

But I cannot clear these three errors and EML persists.

Surely it cannot be a coincidence? Struggling to find info on reference voltage open circuit, but sounds like something is faulty or not connected on the circuit. I’m not sure if that is the cause of the other errors or a symptom…

I don’t really have time to play around with it at the moment, so could do with handing this to someone fairly local who is good with the elecs and troubleshooting these things to have a look

.

 

[mmi]

Heater support pump and adblue heaters seem to activate?

What do you mean? You can hear the pump and the heater actually is drawing current? Or just that the output tests activate?

 

[T6_FunBus]

What do you mean? You can hear the pump and the heater actually is drawing current? Or just that the output tests activate

Output tests activate, I assumed they would fail if the ECU could not activate the units?

It is impossible to hear the pump over the sound of the engine with my head in the engine bay.

 

[mmi]

Output tests activate, I assumed they would fail if the ECU could not activate the units?

Ok, thanks for the clarification. I'm not sure if the output tests actually result as fail (not seen one failing yet). Most of them seem only to drive output lines/states to a defined state regardless other conditions normally required (e.g. engine off/running). Thus the user must judge pass/fail himself - based on some other criteria. E.g. output test for radiator fan run engine off is a quite impressive one... no question when it's a pass...

However, some procedures under Basic settings do report back a bit more - but I'm still not sure if they actually have built-in pass/fail criteria. The feedback seems to be more of type "procedure did run correctly" - but seems that still user has judge the pass/fail himself.

It is impossible to hear the pump over the sound of the engine with my head in the engine bay.

I'm pretty sure I have done also the heater support pump test without engine running - then the pump can be clearly heard.

For the AdBlue heater test one could monitor heater current by using measurement values (available simultaneously with output test in VCDS). However, I haven't managed to do the same with OBDeleven - it seems to cease the test when trying to watch live data at the same time.

 

[T6_FunBus]

Thanks for this, strange, I tried activating with ignition on initially but it just reported error, so I thought it needed the engine running. When I started the engine then they would activate.

Thats a shame, you’re right, I can’t live monitor and do output test at the same time.

I’ll have a think, I might do a bit more troubleshooting if I get chance but I am going to be pushed and using the van to go away next weekend.

Hopefully it will be OK, but may need to just get it in somewhere soon.

 

[mmi]

I'm pretty sure I have done also the heater support pump test without engine running - then the pump can be clearly heard.

Thanks for this, strange, I tried activating with ignition on initially but it just reported error, so I thought it needed the engine running. When I started the engine then they would activate.

Just to confirm - the test runs also with only ignition ON (engine not running).

[T6_measured] 01-Engine - Built-in tests for electrical coolant pumps

Yet another set of engine's built-in tests to try. HOW-TO run engine's built-in test for EGR cooler pump IGNition ON (engine not running) VCDS > Select > Engine > Output test > IDE00879-EGR cooler pump Select "Measuring Values" Pick up e.g. the following data items for monitoring - the same...

www.t6forum.com

Thats a shame, you’re right, I can’t live monitor and do output test at the same time.

For testing heater support pump there is not much to monitor except audible pump sound so initiating the test by OBDeleven would be just fine.

 

[T6_FunBus]

Just to confirm - the test runs also with only ignition ON (engine not running).

[T6_measured] 01-Engine - Built-in tests for electrical coolant pumps

Yet another set of engine's built-in tests to try. HOW-TO run engine's built-in test for EGR cooler pump IGNition ON (engine not running) VCDS > Select > Engine > Output test > IDE00879-EGR cooler pump Select "Measuring Values" Pick up e.g. the following data items for monitoring - the same...

www.t6forum.com

For testing heater support pump there is not much to monitor except audible pump sound so initiating the test by OBDeleven would be just fine.

Ok thanks, I’ll try again, but first time I fried OBDeleven just kept saying ‘error’ when trying to run tests with ignition on.

 

[T6_FunBus]

Does anyone have the part number for the ‘heater support pump’.

Some parts places list it as a ‘parking heater waterpump’. But not sure if they are all the same or different depending on model.

This is listed for 2015> 2.0 tdi 150

Water Pump for Parking Heater fits VW TRANSPORTER Mk6 2.0D 2015 on Auxiliary New | eBay

AUDI A3 Sportback (8VA, 8VF) 35 TDI Hatchback Diesel 07/2018 10/2020 FWD 16 150 110. AUDI A3 Sportback (8VA, 8VF) 30 TFSI Hatchback Petrol 07/2018 10/2020 FWD 12 116 85. AUDI A3 Sportback (8VA, 8VF) 30 TDI Hatchback Diesel 07/2018 10/2020 FWD 16 115 85.

www.ebay.co.uk

Will unplug and test voltage etc first, but may need to like up a new one.

One thing I have noticed is like a gurgling noise since I had the van once parking up, from the centre-ish low down behind the dash (gear shifter area). I just assumed it was normal and hot coolant bubbling / circulating through the pipes to the matrix when switched off. Maybe it was the pump on ots way out? Or maybe its just normal.

 

[T6_FunBus]

Greetings, tried output test again and it did work this time with ignition off, and all three electrical pumps can be felt and heard.

Still have same errors though, reference voltage and heater support pump short to ground (and adblue heater end stage fail).

Thanks.

 

[T6_FunBus]

I’m starting to think as the pump appears to be working that it is a voltage error. The pump is clearly getting enough volts to opperate, so perhaps an internal or supply issue showing less than expected voltage.

I won’t have chance for a while to take a look, but when I get chance I’ll pull the intake pipe and then the pump connector and check the 12v supply on the connector pin.

 

[T6_FunBus]

Just revisiting this, have had no EML for a while, with some ‘supply voltage’ minor errors in ECU for Heater Support Pump, which I think I identified as the one at the back of the engine (between air box and turbo intake). It works, as I have heating in the cabin just fine, and ouput tests confirm it is working. I can feel and hear it when I request it to activate or stop.

Its really annoying as its causing an EML, even though the bloody thing is working just fine.

Any ideas on how to resolve? Should I just buy a new one and replace it?

 

[T6_FunBus]

Update for anyone searching, pump replaced, same problem. Wiring replaced, same problem. The search continues.