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Wiring Info
Wiring Info
Well Guys,
I am not one for giving up but I think I will have to with this one, Previous history:
Thanks to all that responded to the last epistle.
Just a reminder of what has been done so far:
Guys,
Subject Xtrail 2005 2.2Dci SCV 129k miles
To date the following has been done:
New recond injection pump
New timing chain etc
New SCV valve (2nd one in three months)
New FR Pressure control valve
New Inter cooler
New electric fuel priming pump
New fuel filter
Carried out relearn three times
Still getting P1272 error code
Engine will not rev above 4000rpm.
Engine been out twice by garage to fully check timing is 100%. All found to be ok.
Full set recond injectors.
Turbo rebuild
At one point the engine sort of stuttered then it revved perfectly up to circa 5500rpm, sweet as a nut, no smoke no nothing.
Now as stated earlier will not go above 4k.
Anyone any ideas.
Any suggestion how small will be appreciated.
A Electronic specialist came last week and plugged in his box of tricks, don,t know what he did but the vehicle started and was absolutely perfect. Like new, no smoke, no hunting no rattles. However when you switch the vehicle off and restart it goes back into not going above 4k rpm.
Reset/clear the code P1272 and it is like new. From this he deduced that the most probable cause would be the main ECU.
New one fitted (2nd hand from reputable source ), purchased with all of the additional electronic boxes and ignition switch, door lock etc.
We are now back to 4k and P1272 (fuel rail pressure valve), when clearing the error code and starting it comes up immediately P1272 and a new one P0628 (Neutral position sensor).
Has anyone ever experienced this before, and finally apart from scrapping it has anyone any further suggestions that I can try?
Best regards,
John
Since this lot above we have done the following:
New Neutral positioning sensor fitted
EGR blanked off
Fuel pump relearn twice
Checked out the O ring on the SCV, found to be ok, carried out relearn again after fitting scv unit.
Still getting P1272 and 0628 error codes.
ECU unit has been removed and checked all serial numbers are identical to the old one, all found to be correct.
car still revving up to 4k rpm.
It gives the impression that it is being stifled/choked down and its just wanting to rev its backside off but there is just something not letting it get to that point.
I have spoken to some really good guys Des from West Yorkshire Engines (Top bloke) and Lee and Andy from Nisstec based in Glamorgan again two really great lads whilst trying to solve this conundrum
After explaining all of the above to them they are like me and are at a loss as to which way to go.
So as this is my last appeal and no one can help there will be loads of parts with approx 10 running hours on them coming up for sale,
Any suggestions however ludicrous will be more than welcome. As said earlier this is the last chance/appeal.
LATEST UPDATE
The latest on the quest to solve this problem is, have checked the voltages on the common rail sensor plug as per instructions
I have 5v on the reference line
The ground line is down to 4.85v and should be battery voltage.
Unplugged the Signal line is showing .49v
Anybody any thoughts on this?
Best regards.
John
I am not one for giving up but I think I will have to with this one, Previous history:
Thanks to all that responded to the last epistle.
Just a reminder of what has been done so far:
Guys,
Subject Xtrail 2005 2.2Dci SCV 129k miles
To date the following has been done:
New recond injection pump
New timing chain etc
New SCV valve (2nd one in three months)
New FR Pressure control valve
New Inter cooler
New electric fuel priming pump
New fuel filter
Carried out relearn three times
Still getting P1272 error code
Engine will not rev above 4000rpm.
Engine been out twice by garage to fully check timing is 100%. All found to be ok.
Full set recond injectors.
Turbo rebuild
At one point the engine sort of stuttered then it revved perfectly up to circa 5500rpm, sweet as a nut, no smoke no nothing.
Now as stated earlier will not go above 4k.
Anyone any ideas.
Any suggestion how small will be appreciated.
A Electronic specialist came last week and plugged in his box of tricks, don,t know what he did but the vehicle started and was absolutely perfect. Like new, no smoke, no hunting no rattles. However when you switch the vehicle off and restart it goes back into not going above 4k rpm.
Reset/clear the code P1272 and it is like new. From this he deduced that the most probable cause would be the main ECU.
New one fitted (2nd hand from reputable source ), purchased with all of the additional electronic boxes and ignition switch, door lock etc.
We are now back to 4k and P1272 (fuel rail pressure valve), when clearing the error code and starting it comes up immediately P1272 and a new one P0628 (Neutral position sensor).
Has anyone ever experienced this before, and finally apart from scrapping it has anyone any further suggestions that I can try?
Best regards,
John
Since this lot above we have done the following:
New Neutral positioning sensor fitted
EGR blanked off
Fuel pump relearn twice
Checked out the O ring on the SCV, found to be ok, carried out relearn again after fitting scv unit.
Still getting P1272 and 0628 error codes.
ECU unit has been removed and checked all serial numbers are identical to the old one, all found to be correct.
car still revving up to 4k rpm.
It gives the impression that it is being stifled/choked down and its just wanting to rev its backside off but there is just something not letting it get to that point.
I have spoken to some really good guys Des from West Yorkshire Engines (Top bloke) and Lee and Andy from Nisstec based in Glamorgan again two really great lads whilst trying to solve this conundrum
After explaining all of the above to them they are like me and are at a loss as to which way to go.
So as this is my last appeal and no one can help there will be loads of parts with approx 10 running hours on them coming up for sale,
Any suggestions however ludicrous will be more than welcome. As said earlier this is the last chance/appeal.
LATEST UPDATE
The latest on the quest to solve this problem is, have checked the voltages on the common rail sensor plug as per instructions
I have 5v on the reference line
The ground line is down to 4.85v and should be battery voltage.
Unplugged the Signal line is showing .49v
Anybody any thoughts on this?
Best regards.
John
-
KimAndersen
- TwoWaves
- Posts: 249
- Joined: Fri Nov 30, 2012 2:53 pm
- Location: Denmark
Re: Wiring Info
Hi John
What a nightmare !
Let me start by saying that I'm not a expert in Nissan engines, but I've collected some vital informations regarding some Nissan engines that may be useful in your case.
Where to start !
Let us start bye looking at the measurement of commonrail pressure sensor which I find a little bit odd that you mean - there should 12 volt on the ground wire !!!!.
There some basic test of the commonrail pressure sensor you must do in order to determind if sensor is operating correct. Check the voltage on the signal wire with key on and the engine off (KOEO) and I belive this output voltage should be 1 volt.
And off course must you also check the power supply to this sensor (5 volt ref.) and ground and if this is possible - check this at the ECU.
The description of DTC P0628 that I´ve from a valid Nissan document is not the same as yours (Neutral position sensor).
My description of the DTC P0628 says : ( Fuel pump control circuit low input - ECM detects a fuel pump control circuit is open or short to the ground )
So you need a wiring diagram to diagnose the DTC P0628 and some basic diagnostic skills to find this fault.
It´s not much, but its a start.
Best regards.
Kim
What a nightmare !
Let me start by saying that I'm not a expert in Nissan engines, but I've collected some vital informations regarding some Nissan engines that may be useful in your case.
Where to start !
Let us start bye looking at the measurement of commonrail pressure sensor which I find a little bit odd that you mean - there should 12 volt on the ground wire !!!!.
There must be 0 volt on ground wire.JohnCX wrote:The ground line is down to 4.85v and should be battery voltage
There some basic test of the commonrail pressure sensor you must do in order to determind if sensor is operating correct. Check the voltage on the signal wire with key on and the engine off (KOEO) and I belive this output voltage should be 1 volt.
And off course must you also check the power supply to this sensor (5 volt ref.) and ground and if this is possible - check this at the ECU.
The description of DTC P0628 that I´ve from a valid Nissan document is not the same as yours (Neutral position sensor).
My description of the DTC P0628 says : ( Fuel pump control circuit low input - ECM detects a fuel pump control circuit is open or short to the ground )
So you need a wiring diagram to diagnose the DTC P0628 and some basic diagnostic skills to find this fault.
It´s not much, but its a start.
Best regards.
Kim
Re: Wiring Info
Hi John!
I had a look at the rail pressure sensor in my wiring diagram and PCM pin data. Here is what you should look for:
Pin 1 (white)(PCM pin 63): KOEO 5 volts.
Pin 2 (red)(PCM pin 49): KOEO 1 V / KOER idle 1,7-2,0 V / KOER 2000rpm 2,0-2,3 V.
Pin 3 (black)(PCM pin 68): 0 V / ground. Should read 0 volts and as Kim wrote, if you measure 4,85 V, check for continuity to the PCM.
Is this car equipped with some sort of tuning box for example KCR which is fitted between the sensor and the PCM? If so, check out the connectors and also try to bypass it. Could be that the you lost the ground and that may, really not sure here how the ground wire behave, pull up the sensors ground pin to nearly 5 V.
As for the fault codes, these are exactly as Kim wrote, so no more to add. Almost forgot ... these three wires going from the sensor to the PCM is screened - at least what the wiring diagram shows – so an isolation test would be a good idea, IE screen to center conductor. Since you have 5 volts on pin 1 you could skip that one and test isolation on pin 2 which probably has, not really sure so guessing a little, high impedance and just with a light load, IE with quiet a high resistance to screen (which has its ground connection PCM pin 67) it would affect the output from the sensor.
Bjorn
I had a look at the rail pressure sensor in my wiring diagram and PCM pin data. Here is what you should look for:
Pin 1 (white)(PCM pin 63): KOEO 5 volts.
Pin 2 (red)(PCM pin 49): KOEO 1 V / KOER idle 1,7-2,0 V / KOER 2000rpm 2,0-2,3 V.
Pin 3 (black)(PCM pin 68): 0 V / ground. Should read 0 volts and as Kim wrote, if you measure 4,85 V, check for continuity to the PCM.
Is this car equipped with some sort of tuning box for example KCR which is fitted between the sensor and the PCM? If so, check out the connectors and also try to bypass it. Could be that the you lost the ground and that may, really not sure here how the ground wire behave, pull up the sensors ground pin to nearly 5 V.
As for the fault codes, these are exactly as Kim wrote, so no more to add. Almost forgot ... these three wires going from the sensor to the PCM is screened - at least what the wiring diagram shows – so an isolation test would be a good idea, IE screen to center conductor. Since you have 5 volts on pin 1 you could skip that one and test isolation on pin 2 which probably has, not really sure so guessing a little, high impedance and just with a light load, IE with quiet a high resistance to screen (which has its ground connection PCM pin 67) it would affect the output from the sensor.
Bjorn
Re: Wiring Info
Kim and Bjorn,
Really appreciate the help guys, will get on to this tomorrow. I will keep you posted as to what I have found.
Sorry to be a pain but there is another issue now and that is the SCV (its the single one not the twin type) on the back end of the High Pressure fuel pump (engine one not tank) the two wires feeding this both have a live feed reading 12v.
Any thoughts?
I am waiting for the local auto electrician to return from holiday to see what he can offer also.
Once again thanks fellas
Best regards,
John
Really appreciate the help guys, will get on to this tomorrow. I will keep you posted as to what I have found.
Sorry to be a pain but there is another issue now and that is the SCV (its the single one not the twin type) on the back end of the High Pressure fuel pump (engine one not tank) the two wires feeding this both have a live feed reading 12v.
Any thoughts?
I am waiting for the local auto electrician to return from holiday to see what he can offer also.
Once again thanks fellas
Best regards,
John
Re: Wiring Info
Hi John and you are welcome!
Here is some information on you SCV:
Pin 1 (Blue)(PCM pin 29) KOEO 0 volt / ground.
Pin 2 (yellow/blue)(PCM pin 10) KOER (2 V/5ms) high side Pulse Width Modulated (PWM).
I am by no means an expert, but I will do my best to contribute with a few things that may be of interest and hopefully being part of a successful repair .
Does not sound right with 12 volts on both sides of the SCV which make me believe that I got wrong diagram with engine code YD22, or? You did not mention if that was measured KOEO or KOER. A high side switch, per information from the PCM pin data, usually has its ground on one side of an actuator and on the other PWM, which does not seem the be the case in your engine unless the ground side (pin 1) is not in contact with PCM ground pin 29 and then you will of course have 12 volts on both sides. So, it could, with other words, be a ground side switching SCV or I may have missed something, what do you think Kim?
Bjorn
Here is some information on you SCV:
Pin 1 (Blue)(PCM pin 29) KOEO 0 volt / ground.
Pin 2 (yellow/blue)(PCM pin 10) KOER (2 V/5ms) high side Pulse Width Modulated (PWM).
I am by no means an expert, but I will do my best to contribute with a few things that may be of interest and hopefully being part of a successful repair .
Does not sound right with 12 volts on both sides of the SCV which make me believe that I got wrong diagram with engine code YD22, or? You did not mention if that was measured KOEO or KOER. A high side switch, per information from the PCM pin data, usually has its ground on one side of an actuator and on the other PWM, which does not seem the be the case in your engine unless the ground side (pin 1) is not in contact with PCM ground pin 29 and then you will of course have 12 volts on both sides. So, it could, with other words, be a ground side switching SCV or I may have missed something, what do you think Kim?
Bjorn
-
KimAndersen
- TwoWaves
- Posts: 249
- Joined: Fri Nov 30, 2012 2:53 pm
- Location: Denmark
Re: Wiring Info
Hi John
I agree with you Bjorn - the SCV is ground side switch.
In terms of the 12 volt on boths pins of the SCV - that doesn't seem right unless you have measured the voltage with connector attached to SCV and the resistance is really low in the SCV - then you would get nearlly the same voltage reading on both pins.
Regards
Kim
I agree with you Bjorn - the SCV is ground side switch.
In terms of the 12 volt on boths pins of the SCV - that doesn't seem right unless you have measured the voltage with connector attached to SCV and the resistance is really low in the SCV - then you would get nearlly the same voltage reading on both pins.
Regards
Kim
Re: Wiring Info
Guys,
What can I say I just wish we lived a bit nearer to each other, I'm in West Cumbria UK Do you know it or been there? Because a few pints of good ale/lager is called for.
I will get on to this tomorrow and let you know the outcome.
I didn't have the plug disconnected so I will unplug and check again. It makes sense if there is low resistance that gave me the reading.
Thanks again fellas,
best regards,
JohnC
What can I say I just wish we lived a bit nearer to each other, I'm in West Cumbria UK Do you know it or been there? Because a few pints of good ale/lager is called for.
I will get on to this tomorrow and let you know the outcome.
I didn't have the plug disconnected so I will unplug and check again. It makes sense if there is low resistance that gave me the reading.
Thanks again fellas,
best regards,
JohnC
Re: Wiring Info
Hi John / Kim!
I would be most delighted to share a couple of beers with you guys but the travel distance, from northern Sweden, is truly an obstacle! I have never been to England, but last year we spent 2 weeks in the Scottish highlands. As a matter of fact, me and my wife have plans for a trip to UK in August or late July. We will see John, someday day I will knock on the door to your workshop.
If you disconnect the CSV you will most probably measure 0 volts on pin 1 and 12 volts on pin 2 if my wiring diagram is the right one as far as pin numbering concern.
Well, back to the SCV measurement and some hints that might be useful. Most DMM’s has an 10Mohm internal resistance which you – but very seldom – may have to take into account when you measure voltage.
Let us say that the SCV has a winding resistance of about 2ohms. One side of the winding is feed by 12 volts and the other goes nowhere – it hangs unconnected just like John’s SCV, well … as it seems. There is of course no current flow through the winding and hence no voltage drop, but as soon as you start to measure with your DMM, current starts to flow and there will be, believe it or not, a very small voltage drop – approximately 2,4uV – across the SCV.
Why is that? The 2ohm winding plus the DMM’s 10Mohm internal resistance will effectively create a resistive voltage divider. If you divide 12(volt) by the total resistance you will get an answer in volts/ohm: 12/10000002ohms=1,199uV/ohm or in fact, by ohms law I=U/R, also 1,199uA, but let us stay with ohms/volt. Now, multiply 2 (SCV resistance) with the answer: 2*1,199=2,398uV and your DMM will then show 12-0,000002398=11,999V with a voltage drop of 2,398uV.
However, these 2,398 microvolts are of no significance in this measurement, I just wanted to clarify this: without the DMM there will be exactly 12 volts on both sides of the CSV and as you all know, there will be no voltage drop without current flowing in a circuit.
An experiment just to show how the internal resistance of a DMM could affect the reading
Feed a 10Mohm resistor with 12 volts, use your DMM and measure what you get on the other side of the resistor and you will find that your DMM reading will show you half of 12 volts (6 volt) and that is because you created a resistive divider with two 10Mohm resistors. Check attached picture.
Sorry, that was a lot of text that will probably make no difference in John’s case, but hopefully useful to someone.
Bjorn
I would be most delighted to share a couple of beers with you guys but the travel distance, from northern Sweden, is truly an obstacle! I have never been to England, but last year we spent 2 weeks in the Scottish highlands. As a matter of fact, me and my wife have plans for a trip to UK in August or late July. We will see John, someday day I will knock on the door to your workshop.
If you disconnect the CSV you will most probably measure 0 volts on pin 1 and 12 volts on pin 2 if my wiring diagram is the right one as far as pin numbering concern.Well, back to the SCV measurement and some hints that might be useful. Most DMM’s has an 10Mohm internal resistance which you – but very seldom – may have to take into account when you measure voltage.
Let us say that the SCV has a winding resistance of about 2ohms. One side of the winding is feed by 12 volts and the other goes nowhere – it hangs unconnected just like John’s SCV, well … as it seems. There is of course no current flow through the winding and hence no voltage drop, but as soon as you start to measure with your DMM, current starts to flow and there will be, believe it or not, a very small voltage drop – approximately 2,4uV – across the SCV.
Why is that? The 2ohm winding plus the DMM’s 10Mohm internal resistance will effectively create a resistive voltage divider. If you divide 12(volt) by the total resistance you will get an answer in volts/ohm: 12/10000002ohms=1,199uV/ohm or in fact, by ohms law I=U/R, also 1,199uA, but let us stay with ohms/volt. Now, multiply 2 (SCV resistance) with the answer: 2*1,199=2,398uV and your DMM will then show 12-0,000002398=11,999V with a voltage drop of 2,398uV.
However, these 2,398 microvolts are of no significance in this measurement, I just wanted to clarify this: without the DMM there will be exactly 12 volts on both sides of the CSV and as you all know, there will be no voltage drop without current flowing in a circuit.
An experiment just to show how the internal resistance of a DMM could affect the reading
Feed a 10Mohm resistor with 12 volts, use your DMM and measure what you get on the other side of the resistor and you will find that your DMM reading will show you half of 12 volts (6 volt) and that is because you created a resistive divider with two 10Mohm resistors.
Check attached picture.Sorry, that was a lot of text that will probably make no difference in John’s case, but hopefully useful to someone.
Bjorn
- Attachments
-
Re: Wiring Info
Hi John!
Have you made any progress on your car? Sorry for very long text in my last post, me and my keyboard was out of control yesterday.
Regards
Bjorn
Have you made any progress on your car? Sorry for very long text in my last post, me and my keyboard was out of control yesterday.
Regards
Bjorn
-
KimAndersen
- TwoWaves
- Posts: 249
- Joined: Fri Nov 30, 2012 2:53 pm
- Location: Denmark
Re: Wiring Info
Hi Bjorn
Thanks for reminding us all about the basic in voltage drop measurement. Sometimes we forget the basic when we are dealing with a faulty car and our focus are a somewhere else in terms of a diagnostic gameplan.
John do you got any news about the xtrail !!!
Regards
Kim
Thanks for reminding us all about the basic in voltage drop measurement. Sometimes we forget the basic when we are dealing with a faulty car and our focus are a somewhere else in terms of a diagnostic gameplan.
John do you got any news about the xtrail !!!
Regards
Kim