Truck Tech Tips are all about real life automotive diagnostics. How to perform tests that will assist with fault diagnosis to make the Technicians life easier. The plan is to create videos that show realistic processes for testing electrics, fuel, SCR and communications systems. The areas will not be limited as we will create videos based on the viewers needs, what YOU need to know and want to see. We want to incorporate oscilloscope testing as this is becoming more and more common and necessary for accurate diagnosis. Hopefully you will get something from the channel that helps you back at the workshop and makes your day to day work life a bit easier 😊
This is fuse 7 in the engine compartment fuse box (next to the pcm). This one fuse feeds a lot of components. Inlet cam solenoid, oil pressure control valve, coolant pump relay, canister purge solenoid, turbo pressure control and bypass valves. It feeds the red/yellow wire to each of these components.
Interesting measurements but I bet if you disconnected the NOx module while the truck was running you'd get a DTC that was shouting that something was wrong with the comms to that unit so most of these measurements could be short-circuited, so to speak.
True, but what if it wasn't on the CAN. I had a NOx fault where the issue was a voltage drop on the earth. Loading the circuit at the sensor proved it. Comms issues are not always relating to comms wires.
Hello there. I haven't specifically seen the MAN 6 wire sensor, but I have seen 5 wire sensors which contain 2 earths, 1 positive and CAN High and CAN Lo. I will have a look out for one and do a video on it. Thanks for the question.
Do you have a video for 5 pins as well? My nox sensor 2 has 5 pins. Yours in video is with 4 pins. I changed the nox sensor and now is failed again. P229 FO9 NOx sensor 2 (cylinder bank 1) has a malfunction. There is a component fault. --NOx sensor 2 (cylinder bank 1) has a malfunction. No signal change: Voltage level is too low.--The switchover between the maximum and minimum values of NOx sensor 2 (cylinder bank 1) is too slow. There is a signal below the permissible limit value. .. i changed one nox sensor and i suspect to by problem with wiring and not nox sensor. Thanks
Hi there, what vehicle is it fitted to? Some 5 wire NOx sensors do no use the 5th wire. So they only have a positive, negative, CAN Hi and CAN Lo. Sometimes you can get downstream NOx sensor issues if the SCR catalyst is not performing as it should.
Is it the same procedure on the Iveco Stralis 450 E5 2007? The problem is that after replacing the sensor, it reports an error: LONG TERM NOX SENSOR FAILURE DTC:45F. By replacing the sensor (from another manufacturer), it reports an error :NOX SENSOR FAILURE DTC:1A3! Three new sensors have been changed and all three are showing errors. I ask for help and advice. Thank you!
Hi there. So there are a few things to consider. Firstly you need to make sure that the NOx sensor that you have fitted is the exact component for your vehicle. Different manufacturers may have CAN High and Low swapped round. Secondly are there any other DTCs stored? Do you have any for EGR for example. The EGR also assists with the reduction of NOx. If there is an issue with this system NOx levels will be higher than normal. Thirdly, does you vehicle have a pre and post NOx sensor or just a post NOx sensor. Potentially the SCR catalyst could be an issue although this is only in extreme cases. Just a few things to consider.
Hi, I would always recommend going for more channels if possible. This means you can measure power/ground and signal at the same time when you are looking at most sensors. Really depends on your budget. I have both, I started with the two channel which cost me £150 ($195). Relatively cheap, but got me used to using the software.
I have a 2008 Midlum and the display/dashboard is not working at all after boosting the battery with a battery staring robot. Everything is working properly except the display. Checked everything the relays and fuses there is no fault. The diagnostics device cant access the display module ... have you meet some similar problem?
Hi, we haven't had that fault, but here are some things you can check. Remember the cluster is just another module so it needs a few things to communicate, powers, grounds and connection to CANbus. If these are all there then the cluster module could be at fault. There are 3 plugs on ours C, B and J. Plug C pin 13 is the cluster ground. Plug C pins 11 and 12 are high speed CAN check your resistance and voltage at these pins. Plug J pins 1 and 2 are diagnostic CANbus, check you have approximately 4V and 1V (CAN Lo and Hi) respectively. Plug J pins 6 and 8 are high speed CAN so check your resistance and voltage there. Finally plug J pins 10 and 23 are power supplies. If you have all of these then it looks like the cluster module (MID140) is at fault.
Hi! As a feedback for the tips above You have right. The fault was at the cluster module, the resistance and the voltage was exact as you mentioned... I'm grateful to you that you answered my question and for the useful answer, we have saved a lot of money (replaced the module with a used one for pennies). Thank you for sharing your knowledge! @@trucktechtips638
Nice job and what a cracking video. Not so common to find corroded fuses and sometimes not possible to see this resistance with the naked eye. Hell of a drop there 👍
The car was a 2012 Audi A4 1.8TFSI. The fuse was number 6 (15A) in the left plenum chamber (next to engine ECU). This powered the engine component supply relay coil and three of the fuses in fuse panel c (at the side of the dashboard). The three fuses where for clutch pedal switch interlock (5A), fuel pump control module (25A) and brake light switch (5A). I used the free wiring diagram CARMIN STD in the app store to find it.
Hi as an aside is there a way of using the NOx sensor to detect Nitric Oxide at parts per million as a stand alone test set, the real one cost $885. I have a iNO generator on my workbench bench and want a test sensor
What an interesting question. I scraped a pass at Chemistry at school so take my answer as one not coming from an expert. In theory, yes, your commercial NOx sensor can measure in the region of 0-1600ppm. The term NOx that is used is only the collective term for Nitrogen Monoxide (Nitric Oxide) and Nitrogen Dioxide I believe. The iNO generator you have is this a respiratory machine? Have a look at this article I found about NOx sensors. There is a fair bit of reading in it but it discusses what the sensor is actually doing. dieselnet.com/tech/sensors_nox.php#:~:text=The%20NOx%20measurement%20range%20is,%C2%B110%20ppm%20%5B3899%5D%20.
Hi Neil. It's an Ancel X6 HD, they retail about £450.00 ($545.00). You get what you pay for with scantools. We haven't had any success with it on Iveco. DAF, engine and SCR faults but no ABS. Volvo, Renault, Dennis pretty good to be fair. The tool allows for 1708 CAN diagnosis which is helpful on these models.
Finally, someone else using a picoscope on a truck! I work on Cummins in the States and just got a 2204a. Thanks for the video and keep them coming please! If you know any others on youtube making videos with a picoscope on a truck please share!
Very good explanation of canbus. Ive worked on HGV's for years (not in dealerships) and have muddled through with very little training. These types of video's are excellent. Thank you 👍
I haven't experienced that myself Matt but to be fair it depends where the break or issue is. Volvo FE/ Dennis's where always bad for the CAN lines breaking right at the Engine ECU so you wouldn't have communication with the module and no DTC's available on the Scan Tool or Instrument Cluster from the ECM.
