Nissan Qashqai 1.5dci 2012 , car is running ok but esp slip lights are on , codes are c1130 and c1132 no coms with the ecm, also have some codes stored on body control and other ecu U1000 , also p0471 logged but dpf pressure sensor reading as should and tested with mityvac and dvom , could this be a problem with the engine ecu or abs ecu ? Or is the can high/low wiring at fault?
I m guessing that you don't have communication with the ABS ECU ??
I would put P0471 on the back burner for now. It could be there because the PCM needs to see wheel speed.
I haven't looked up those definitions. Your CAN trace looks ok.
What network does the scan tool ride on for Serial Communication ??
You need to get a wiring diagram and establish what is on that network and see which ones are not talking. If it is only the ABS then load test Powers, Grounds & Comm lines to it.
What network does the scan tool ride on for Serial Communication ??
Hi, thanks for your reply, I'm not sure what you mean by "What network does the scan tool ride on for Serial Communication" , I'm using a hella gutmann scan tool.
I can communicate ok with ABS/ESP unit and check parameter's, sometimes the esp lights do go out if I clear p0471 but they come back showing c1130 and c1132. I also have p1525 stored
The U1000 codes have not came back after been cleared , I have CarWeb data and checked the connector pins for lives and earths and all good to the ABS
would the ABS unit coms go direct to the ECM via canbus?
I have a Autoboss scan tool and if I communicate with tis tool the ECM says loads of codes, I also seen to have problems trying to actuate anything from scan tool.
Also the customer told me she put petrol in the car and drove then cut out and rac removed fuel/filter, the engine sounds perfect and runs ok not sure if any of these faults could be related.
My approach would be to sort out your P0471 DTC first. For several reasons:
* P0471 may affect the Engine Control Modules ability to control engine torque, which is crucial for TC/ESP functionality.
* I've found that "U" Codes, don't necessarily mean that you have lost communication. I've seen plenty cases where a "U" code has set for Invalid data that has been sent over the bus e.g a steering angle sensor.
* I think it's unlikely you have a intermittent beak in the wiring. I don't know the topology of the BUS, but what's the chance of the break being on the bus so that it only affects the ABS module and on top of that the fault only affects the bus when your not communicating with it or looking at the trace with the Scope.
I also think your c1130 and c1132 DTC's may also be Invalid data DTC's rather than No Comms faults. Do you have OEM information on the conditions for setting these DTC's?
My advice to my Techs is "as a rule of thumb, ignore "U" DTC's UNLESS there is an actual functional issue i.e. you cannot communicate with that module or modules. I've haven't seen any OEM service info or vehicle data that tells you the conditions for setting "U" codes and I've never seen freeze frame data for "U" codes.....so far.
Sorry for the late reply!
STC forgive me messing with your mental health I have that problem with most people !
What I meant was I can talk to ABS module and parameters which are throwing C1130 and C1132 codes and what this is saying is the ABS unit is not able to talk to engine control module.
Scan tool connects to engine ECU ok also. (saying that hella gutmann ok Autoboss throws every code stored in ecm up)
I never got to the end of this and not had the time to spend anymore time on her at the moment.
I think the C codes are ghost codes and not coms error as if the p0471is cleared the slip lights go out but soon come back with p0471.
Hi Mark
I think you are correct in what you are saying, Ive seen a Nissan bulletin regarding c1130 and c1132 coming on through the dpf blocked or blocked pipework, there is one pipe on the dpf going to pressure sensor this is all clear and in good health, a metal pipe going from the exhaust manifold and this can get clogged also but clean with no blockages! The car was reading 22 grams of soot which is to much , The dpf was not in good condition so has been changed codes cleared and live data still reading 22 grams of soot eh!, The pressure sensor has been tested on bench with mity vac and dvom and all looks good even when on the car the data at the pressure sensor is reading the same at ECM, continuity to ecm all ok.
Could it be EGR ? or faulty ECM software ?
As you say U codes are probably invalid data also as STC says the can looks ok, Just a quick question also how do find the topology of a network?
regards
The topology of the Bus would normally be in the OEM schematics. someone like Snap-On or Auto-Data might have that sort of thing in there service info. Or ask your nearest Nissan dealer for a favour to get the page out the OEM schematics.
There's only one pipe from the DPF? Before or after the DPF?
The soot accumulation % could be a learned over time value, so may need time to relearn. Is the a function to reset the value via scan tool.
With just the Ignition on the DPF Sensor should read the same as the Barometric Sensor, does it?
Is there a reset procedure for the delta pressure sensor ? You have proved the sensor reads correctly electronically the pcm will need to refresh the soot values as these will be equated or calculated by algorithms and the delta p values.
Roadtest the vehicle monitoring the soot load and delta p . Look for it building up soot to rapidly .
If that's the case whatever makes black smoke in a diesel will block dpf so thinks basics.
Danny
Thanks for all your comments , I did reset the ECU learning data but would say all done but then comeback saying partially full again.
Any how after contacting Nissan they told me the customer was told to fetch the car back regarding a recall of the software within the ECU but the customer never returned the car!
My customer bought the car not knowing this info.
Vehicle been in and all problems cured, Thanks for your info and help guys