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Large MPVs -- Ford Galaxy / VW Sharan / SEAT Alhambra: => Ford Galaxy / VW Sharan / SEAT Alhambra => Topic started by: Sharan1998 on February 28, 2018, 07:25:08 PM

Title: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on February 28, 2018, 07:25:08 PM
VCDS Lite shows: 65535 -  Internal Control Module Memory Error
            35-10 -   - - Intermittent

I have strange feeling around my anus, that MAP sensor in ECU is blind. Does fully registered VCDS-Lite shows MAP sensor readings in some group?
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: johnnyroper on February 28, 2018, 11:05:51 PM
Yeah registered copy will give map readings in measure blocks.
I take it that was in engine controller? A quick google shows it is more airbag controller related?
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 01, 2018, 06:38:11 AM
Yeah registered copy will give map readings in measure blocks.
I take it that was in engine controller? A quick google shows it is more airbag controller related?
Address 01: Engine       Labels: 028-906-021-AHU.LBL
   Controller: 028 906 021 GS
   Component: 1,9l R4 EDC   00SG  1904
   Coding: 00002
   Shop #: WSC 00020
   VCID: 66BF4A4E117F
2 Faults Found:
65535 -  Internal Control Module Memory Error
            35-10 -   - - Intermittent
00575 -  Intake Manifold Pressure
            17-10 -  Control Difference - Intermittent
Readiness: N/A

Is it MAP actual or MAP specified or...?
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Chrispb on March 01, 2018, 08:15:13 AM
Early cars have the engine ECU behind instrument cluster with the MAP sensor inside and has a small hose connected to it which goes to the air charge pipe.
On the inside of the ECU there's a short piece of hose that perishes with age.
This can be sorted but requires removal of the ECU to access.
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: johnnyroper on March 01, 2018, 08:40:43 AM
Address 01: Engine       Labels: 028-906-021-AHU.LBL
   Controller: 028 906 021 GS
   Component: 1,9l R4 EDC   00SG  1904
   Coding: 00002
   Shop #: WSC 00020
   VCID: 66BF4A4E117F
2 Faults Found:
65535 -  Internal Control Module Memory Error
            35-10 -   - - Intermittent
00575 -  Intake Manifold Pressure
            17-10 -  Control Difference - Intermittent
Readiness: N/A

Is it MAP actual or MAP specified or...?

Registered will give specified and actual MAP reading.
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 01, 2018, 08:49:38 AM
"Mouthtested" the pipe going to ECU from motor side - ain't leaking. VCDS Lite shows MAP actual and MAP specified numbers running. EGR duty cycle is about 19% and boost control(?) is 91 and something %. When speed is rising to about 85 km/h, MAP actual jump ower 1900 (mbar?), EGR duty cycle is going ower 50% and boost control under 70 %- back to normal readings just after switch off and start again.
 Just sucked the pipe going from air cleaner to some valve (18?) from air cleaner end - ainīt holding vacuum inside.
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Chrispb on March 01, 2018, 09:10:18 AM
Maybe but those are the error codes received when pipes perished
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 01, 2018, 02:29:38 PM
AHU wastegate actuator - operated with vacuum or pressure?
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: johnnyroper on March 01, 2018, 03:27:46 PM
Think it is vac operated via the n75 valve, if memory serves correctly iturbo is standard wastegate and not vnt.
Trace vac pipe from turbo to the n75 and check for splits etc,you can also activate n75 with vcds to make sure it is operating.
Have you checked basics like good vac from the pump and condition of all vac pipes?
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 01, 2018, 04:59:01 PM
Mmm.. actuator is a pressure operated, pipe from turbo thru n75 to wastegate actuator. I connected the pipes straight with eachother. Nothing changed - wastegate stucked?
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: johnnyroper on March 01, 2018, 06:58:28 PM
Is it defo pressure operated? What is routing of the pipe to the n75 is it off the vac pump pipework or from side of turbo or inlet manifold?
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 02, 2018, 06:42:40 AM
http://www.vwt4forum.co.uk/picture.php?albumid=18698&pictureid=175182 (http://www.vwt4forum.co.uk/picture.php?albumid=18698&pictureid=175182)

Connected the pipes straight from turbo to boost control valve. Like the old school TDI-s had.
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 02, 2018, 07:00:09 AM
http://pics.tdiclub.com/data/516/A3_98_Jetta_TDI_Pressure_Vacuum_Diagram.jpg (http://pics.tdiclub.com/data/516/A3_98_Jetta_TDI_Pressure_Vacuum_Diagram.jpg)
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 02, 2018, 08:47:34 AM
Wastegate working on 0,5 bar(loaded manually).
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: johnnyroper on March 02, 2018, 09:27:41 AM
What you are looking at is either map sensor issues causing ecu to operate n75 at incorrect time. Check the pipe in ecu as suggested. Or the n75 is is sticking in my opinion.

0.5 bar opening of wast gate is about normal for ahu so to have map spikes and limp mode activated it all points to 1 of the above being at fault.
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 02, 2018, 12:29:49 PM
Wastegate was stucked(moving much easyer after oiling). VCDS shows MAP actual numbers running up and down. Changed just pipe from turbo to n75.

To be continued...
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 02, 2018, 01:51:01 PM
All pipes, belonging to n75 was changed. Wastegate is fine. Nothing changed.
Big boys says that MAP sensor inside ECU is not blind. Blind is barometric pressure sensor. Gives 1080 mbar when engine started and when start driving goes to 693,6 mbar and stays until motor is switched of. Your comments, please.
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: johnnyroper on March 02, 2018, 01:55:48 PM
Have you checked the internal MAP sensor pipe in ecu? Itís showing all signs of it being perished/split affecting readings.
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Chrispb on March 02, 2018, 02:24:02 PM
Have a read here.

http://www.fordgalaxy.org.uk/ford/index.php?/topic/22717-how-to-ecu-removal/
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 02, 2018, 04:13:33 PM
Internal MAP sensor gives good numbers. I "mouthtested" the pipe going to the ECU - its fine. VCDS understand when i disconnect the pipe from manifold.
Big boys says, that replacing barometric pressure sensor cost 90 EUR. Remove ECU, post it to them, and next day they post it back.
 If we take a look at this diagram - http://pics.tdiclub.com/data/516/A3_98_Jetta_TDI_Pressure_Vacuum_Diagram.jpg (http://pics.tdiclub.com/data/516/A3_98_Jetta_TDI_Pressure_Vacuum_Diagram.jpg) we can see, that atmospheric pressure sensor(barometric pressure sensor?) is in valve n18 and a wire goes from n18 to ECU. Any ideas?
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: johnnyroper on March 02, 2018, 04:23:39 PM
I donít think you will find atmospheric pressure is measured by N18 that pipe back to air filter is just the N18 vent thatís used to release the vac so egr valve closes when demanded
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: johnnyroper on March 02, 2018, 04:25:44 PM
You say you mouth tested it but will that prove the pipe inside ecu,can you apply up to 19psi with your mouth?
As already said a few times you need to take the ecu out and physically check the internal pipe to map sensor.
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 02, 2018, 05:38:03 PM
Just loaded pipe to MAP sensor with 1 bar - pipe is fine. Motor going to limp mode, when difference between specified and actual MAP rise to about 400 mbar. Specified 1300mbar - actual 1700mbar. Actual canīt rise so high when pipe is damaged.
When pipe is damaged, then specified is higher then actual, right?

Baro readings are poor - 693,6mbar. Need to be about 1010 mbar.

Question is: are the BARO sensor in same household with MAP sensor?
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: johnnyroper on March 02, 2018, 06:20:45 PM
I go back to n75 sticking or the wastegate actuator not operating correctly then if you are having overboost. You need to try a new n75 in my opinion.
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: Sharan1998 on March 02, 2018, 06:25:53 PM
Going limp mode when boost is about 1700mbar. Is it too high?
Title: Re: Sharan 1.9 TDI AHU limp mode
Post by: johnnyroper on March 02, 2018, 07:01:06 PM
Thatís about right as the ecu accounts for slight spikes before it limps.