Disco 3 (LR3) P0046-00 (28) Error / hopefully resolved

So spent some time removing what was left of the engine cover insulation , then fitted all new , definitely not the best of jobs but used all my off cuts up

got another new roll for under the bonnet and didn’t want to cut into the new roll

so that’s another little project out the way , to dam cold to work on the disco today , I’m hoping Sunday will be nice , think I’ll start by removing the viscous fan , then try and get that split turbo air inlet pipe out

plus on top of the radiator there’s a fan cowl with 2 x plastic threads for 2 x screws, alas the screw holes have been stripped , so going to see if I can use my glue gun, in filling up the holes then running new screws into the hole , alas don’t know if it will work , but really don’t want to get another cowl panel , but those holes are important as it holds down the air filter intake pipe

Found some online pics of that cowl, can see in the 2nd picture the screw holes but alas on mine they’ve been completely stripped

that’s why I thought if the glue gun will work ??

If anyone does know another way how to repair the screw holes please I’ll be always very grateful, many thks

Think I’ve now got everything , lol, won’t be using that metal pipe though because of the massive hassle of getting the old one out

fingers crossed this also helps others who need to change there plastic inlet pipe , , will at the same time fit the silicone hoses

So a quick update

got all the pipes out, what a nightmare that was, so I’ve noticed some oil on the intercooler fins, so I think the next step will be to smoke test the intercooler itself to ensure it’s 100% sound, also now have access to the turbo actuator connector , removed and cleaned that but thinking of doing a continuity test between that and the ECM to ensure all the wires are ok

talk about opening a can of worms, lol, but just trying to do things step by step , eliminating things as I go

with a mirror I also checked the turbo fan, sorry don’t know what the proper name is, spins freely with no side movement at all

took me ages to undo a bolt near the ABS pump

bet it’s just a bad wire somewhere that’s preventing the turbo signal getting back to the ECM

current faults with this actuator showing N/A

Engine TDV6
P120F-00 (28) Fuel pressure regulator excessive variation
P0402-00 (68) Exhaust gas recirculation flow excessive detected
P0046-00 (28) Turbo/supercharger boost control solenoid - circuit range/
performance

So been studying the wiring diagrams, as u do, lol, got to now try and find the SJ joints , think there in the ECM itself , looks like I’ll be removing the TCM and ECM modules and then belling out the wires from one end to the other , oh joy,

can also see the MAP sensor connects onto the VGT side of the turbo, will also check all my earths just in case one is bad

May i ask a daft question please of why when I look on the live data the turbo Boost pressure actuator- Bank 1 comes up NA

reason is does the turbo actuator arm have to touch something like a microswitch or simply there’s a bad wire/ ground where the ECM simply can’t get the information back

just trying to think of this error logically so any help I’ll be extremely grateful please

think my next steps will be to put a smoke machine with around 4-5 Psi onto the intercooler to ensure that’s 100% sound
Then do a continuity between the ECM and turbo actuator connector

just baffled abit about the N/A

many thks as always

Also done some live recording logs, got the disco up to temperature , figures are after each graph log, maybe someone might see something I’m missing , done the recording whilst driving then coming back to idle , thks so much

Just been messing around with that new Curien N2 , didn’t realise it had other settings etc , also see if u turn it landscape can then select a graph , plus using a BNC connector can use a clamp meter

will be interesting using a breaker box on the OBD2 connector and the meter on a graph setting what the canbus signal looks like , along with learning what good and bad signals look like, do have an ordinary digital multimeter to compare if I’m unsure of some readings

sorry I’m waffling as per usual, lol

Also don’t know what this means in the manual


Can the N2 graph square waves?
Yes. The N2 is a full TRMS meter that has the ability to shut off TRMS and give a true waveform measurement. You can view
squarewaves and all waveforms in the graphing screen. *Note you must activate "Waveform" function to view square waves and shut
off TRMS measurements. Also the N2 could be considered a SO but becuase we do not designate the N2 an oscilloscope we do not
classify this.

Morning kiddo,
Wow OK... Some nice tools first of all.
Looking at the graphs, (not experienced) the turbo and the map and the map have a similar relationship which is logical.
Quite simply, an ignition key test.
The turbo actuator will run full course and smoothly when the key is turned to the on and then to to off position?
Now, just because it does this engine hot and cold doesn't meant inside a contact or position sensor isn't faulty.
These things are a rediculous idea sat next to a smoking hot turbo!!
As you know the ecu knows where the turbosl vanes should at every given point, one sticky vane on the assembly will jarr the whole mechanism and cause an alert.
The motor itself also has position sensors to help the ecu, if the position sensor inside doesn't return a signal then these faults can occur.
So, à possible physical sticking mechanism, cassette doesn't return as expexted= sensor out of position=
Missing signal, results in a sensor fault. As the ecu doesn't do physical monitoring.... I know you know this , but until you can specifically examine the turbo cassette and or the turbo vane assembly.. It could be an interesting investigation...
Any time I've seen position faults, eg. Sensor out of position... It's usually a jamming mechanism which will clean up and then shortly after the motor and or gearing will fail due to the sticking mechanism!!
But as these turbos are not found in bloody kinder eggs I can appreciate your need to be 100% sure about replacing it..

Mark Piercy said:

Morning kiddo,
Wow OK... Some nice tools first of all.
Looking at the graphs, (not experienced) the turbo and the map and the map have a similar relationship which is logical.
Quite simply, an ignition key test.
The turbo actuator will run full course and smoothly when the key is turned to the on and then to to off position?
Now, just because it does this engine hot and cold doesn't meant inside a contact or position sensor isn't faulty.
These things are a rediculous idea sat next to a smoking hot turbo!!
As you know the ecu knows where the turbosl vanes should at every given point, one sticky vane on the assembly will jarr the whole mechanism and cause an alert.
The motor itself also has position sensors to help the ecu, if the position sensor inside doesn't return a signal then these faults can occur.
So, à possible physical sticking mechanism, cassette doesn't return as expexted= sensor out of position=
Missing signal, results in a sensor fault. As the ecu doesn't do physical monitoring.... I know you know this , but until you can specifically examine the turbo cassette and or the turbo vane assembly.. It could be an interesting investigation...
Any time I've seen position faults, eg. Sensor out of position... It's usually a jamming mechanism which will clean up and then shortly after the motor and or gearing will fail due to the sticking mechanism!!
But as these turbos are not found in bloody kinder eggs I can appreciate your need to be 100% sure about replacing it..

Click to expand...

hi mate

can’t thank u enough as I don’t mind admitting am over my head with this but just taking out little chunks at a time so to speak

I’ve done the followigm so far, got a new can of silicone spray and a bent up coat hanger , moved the turbo actuator arm back and forth whilst spray the arm and the arm joints , felt a lot better after I had done that

removed all the air filter inlet pipes from the filter itself to the turbo, as there were signs of a split, alas nope it was just the way the pipe was made , removed old intercooler pipes , going to replace them with silicone ones and T bolts

indeed regarding the ECM, was going to back probe them and doing a continuity test from the ECM to the turbos actuator connector , seeing that as the pipes are removed I’ve got decent access to it

many thanks as that’s what I was wondering with regards why the boost pressure actuator comes up N/A , so that makes sense if it can’t travel the required movement it can’t send the message back to the ECM or indeed a broken wire

learning a lot with regards to this along with understanding some sensors have a 5Vdc reference , so can test them after I’ve back probes the turbo and can then do the Map sensor to ensure it has the suitable Vdc ,

looking at the wiring I see the turbo wiring goes directly to the ECM, however in further looking it has SJ2 and SJ3 , after a lot of searching I see these are connected into the ECM

also another strange one is the Supplementary engine coolant temperature showing minus 40c , haven’t got a clue what or where this is , can’t even find it in any parts list so misterfied by this

thanks so much once again and will update u as I do tests one by one, oh and can see signs of oil on the intercooler fins so will do a smoke test for that to ensure 100% it’s not leaking

many thks, my pops treated me to the Curien N2 for xmas

extremely grateful for the help and such a steel learning curve so any help is really appreciated , plus just found some new flexible split conduit as I’ll be replacing a lot on the engine seeing it’s very brittle

hope ur good and once again very grateful to u, thank u

Your more than welcome kiddo
Do you have a fbh on-board?
https://www.turbosacer.com/product/scaer-sa1142-smart-electronic-actuators food for thought.
https://www.aet-turbos.co.uk/what-is-a-turbo-actuator/
A Final snippit https://www.melett.com/technical/why-turbos-fail/rea-srea-electronic-actuators-faq/
It's not point at the actuator but to add to your knowledge base.

You'll like this one..

Mark Piercy said:

Your more than welcome kiddo
Do you have a fbh on-board?
https://www.turbosacer.com/product/scaer-sa1142-smart-electronic-actuators food for thought.
https://www.aet-turbos.co.uk/what-is-a-turbo-actuator/
A Final snippit https://www.melett.com/technical/why-turbos-fail/rea-srea-electronic-actuators-faq/
It's not point at the actuator but to add to your knowledge base.

Click to expand...

thanks a million and I’ll check them out , honestly mate I can’t thank u enough

as the weather has warmed up going to pop outside and try and get the battery out, it’s an 019 so bloody heavy

then I’ll see if I can at least trace where the turbo loom goes, plus a continuity test as never know the loom because it must run up the side of the engine if a wire has burnt through etc , but at least the continuity test will tell me if there’s an issue between the actuator and ECM

shame my kids have moved away as don’t mind admitting seriously struggle trying to do things and then end up in agony with my back but alas got to make some progress

I’ll also remove and clean the earths as see there’s a cluster of 3-5 earth wires that go to the ecm , just in case it’s something like a bad earth , just don’t want to miss anything

think I’ll also start writing down what I’ve done, ie from what pin to what pin etc , so I suppose like a check list

extremely grateful and will of course update the thread of how I get on

Mark Piercy said:

You'll like this one..

Click to expand...

many thks, will have a watch of that later , looks really interesting

must add that indeed when I turn the ign on/off the turbo actuator motors back and forth , plus my egrs are blanked

just so grateful to u , can’t even begin to say how much this is helping me

So rain stopped play, lol

managed to get the battery out and the TCM, so I could at least give the pins a good clean because after I had checked the pins before and reconnected everything I got a long list of TCM errors , used some mannol contact cleaner and very careful used the files to get rid of the green build up

Just a few pics of before and after , at least that a little step done

thks again for all the fantastic help as very grateful

Before



After cleaning

gstuart said:

So rain stopped play, lol

managed to get the battery out and the TCM, so I could at least give the pins a good clean because after I had checked the pins before and reconnected everything I got a long list of TCM errors , used some mannol contact cleaner and very careful used the files to get rid of the green build up

Just a few pics of before and after , at least that a little step done

thks again for all the fantastic help as very grateful

Before

View attachment 257061 View attachment 257062

After cleaning

View attachment 257063 View attachment 257064 View attachment 257065 View attachment 257066

Click to expand...

Bloody hell, you wouldn't have thought this be possible with the modern plugs used now would you....

Mark Piercy said:

Bloody hell, you wouldn't have thought this be possible with the modern plugs used now would you....

Click to expand...

indeed and seems it’s quite common for the TCM pins to turn green , has something to do with water ingress as it’s also known water can get into the pollen filter , water normally gets past the bonnet seal

Will use the smoke machine inside the cabin but then admittedly I thought how am I going to turn it off , my auxiliary fuse box cables pass into the cabin via the bulkhead , so I’ll put the smoke machine on top of the engine and push the smoke machine nozzle into the cable entry hole, that way I’ll be able to turn it off , plus not having to open any doors as that would indeed defeat the test

Think it will take a while to completely fill up the cabin area but have ment to do it for ages as got an annoying water ingress on the passenger side , but all the door seals etc are original so wouldn’t surprise me if it’s getting past there

Also didn’t realise all the doors have 2 x seals , plus did get a set of 4 x window seals last year , thought the best thing was maybe having my iPad handy and take a video so that way I can go back through it so can see where the smoke is escaping

once it warms up I’ll do that continuity test between the actuator and ECM , dreading it seeing there’s so many wires

thks again

Can you trace the wires from the associated pins to and from the turbo with the plugs off?

gstuart said:

indeed and seems it’s quite common for the TCM pins to turn green , has something to do with water ingress as it’s also known water can get into the pollen filter , water normally gets past the bonnet seal

Will use the smoke machine inside the cabin but then admittedly I thought how am I going to turn it off , my auxiliary fuse box cables pass into the cabin via the bulkhead , so I’ll put the smoke machine on top of the engine and push the smoke machine nozzle into the cable entry hole, that way I’ll be able to turn it off , plus not having to open any doors as that would indeed defeat the test

Think it will take a while to completely fill up the cabin area but have ment to do it for ages as got an annoying water ingress on the passenger side , but all the door seals etc are original so wouldn’t surprise me if it’s getting past there

Also didn’t realise all the doors have 2 x seals , plus did get a set of 4 x window seals last year , thought the best thing was maybe having my iPad handy and take a video so that way I can go back through it so can see where the smoke is escaping

once it warms up I’ll do that continuity test between the actuator and ECM , dreading it seeing there’s so many wires

thks again

Click to expand...

One thing at a time ma boy!