Data sheet Info
Hi there, I am trying to get as much exposure with this question as i can in case i can brush it by someone who knows the answer for certain. Sorry i dont have a Vin for this car. It is a no start with the above code setting every time after 10 seconds of cranking. There is an intake and exhaust cam sensor. Neither sensor is producing a signal when tested with scope, 5volt supply and ground are present for both sensors.
At least one of the cam shafts is turning, confirmed that with one sensor removed. While that sensor was out i used metal object to pass by the sensor, still no signal on scope. I believe this would be classified as a hall sensor. I have kept this bit of information but I should maybe disclose, both cam sensors have been replaced (BWD sensors) before it came to us. So as someone suggested manually pulling signal high then watching if sensor can pull it low would be great..... but then again, if the sensor is SUPPOSED to generate its own 5V and the sensors that are installed are working the other way.... I still go up the same creek.
Crank sensor is working fine.
So now the question, Should the PCM be providing a 5 volt reference on the signal wires...? tested when sensors are unplugged and key on? Voltage stays at 0 when sensor is unplugged or plugged in or engine cranking. The problem then is, are the sensors both bad or is the pcm bad for both circuits?
Very grateful if someone can answer this with confidence! In electronics this is something one would likely look for in the data sheets.
An additional question, if we end up putting in a PCM... can this be done using NERS or will NATS then become an impassible hurdle?
In my experience it can be either way. Most FCA I have seen have a 5 volt bias on the signal wire. Some makes are at zero volts. Is the crank sensor a hall effect? If it's working and it does not have 5 volts on the signal then I would say it's safe to say the cam sensors are the same. As far as I know the PCM only uses the 5 volt bias on the signal for circuit integrity, not for operation of…
Wonder what the scan data showed in reference to sensors, etc before he went under the hood. Always go the easiest route first then move towards the harder things. Something didn't seem right in the information. For future reference get something such as a sensor simulator which helps you verify if the sensor is working properly. Aeswave.com appx $399 U.S. last I checked when I…
Hi Dale, yea that TTL out on the E-scope would help out alot. In this particular case tho I am not sure it would confirm the sensor operation. What were you wondering about in the information? Maybe I could clarify.
Just one maybe stupid question, are you sure it's electrical and not mechanical (like a broken timing chain?)
Very little information from nissan on testing p0340...I would think if you have both cam sensors not reading you should have a p0335 and p0340....does the engine sound funny...maybe the camshafts are not turning?? If the cam sensor is a pull down sensor you could supply voltage the signal through a 10000 ohm resistor and see if the sensor can pull the voltage down....if it is a pull up sensor…
You could also try pulling the sensor out and passing a screwdriver in front of it. Just to see if it will do anything. This should pull the voltage up to 5. While the sensor is out you could have someone crank the engine to see if the cams are turning. It would be strange to have both not reading at all. I just took a look at the diagram and it looks like the signal wire is pin 3 on both…
Oops, I see you already tried the metal in front of the sensor trick. Sorry about that. :)
I can't answer your question but I can offer up my personal advice. When I worked for Nissan on more than one occasion I encountered many aftermarket crank and cam sensors that didn't work. Since leaving the dealership world I only use OE sensors. This of course if they are available,,,, I don't even consider cost.
Your two camshaft position sensors have a 5 V power on the brown wire, and a ground (signal return) on the white wire. The other wire on the sensors is the signal wire. If you do not have a 5V reference at the sensors, find out why. Is there a short to ground somewhere in the harness, or is the PCM dead. If all else fails, find the brown wire at the PCM and clip it in a place that will be easy…
Do you have spark?fuel? While the motor is cranking check for tach movement if it’s registering rpm then pcm and sensors are operational and there’s another reason for no start don’t overlook the basics.good luck
Check the reluctor at the rear of the camshaft. They are pressed on and can sometimes turn out of phase.
Hi just came from a Nissan dealer for something unrelated to this and showed your post to a master tech he says check condition of oil if it’s sludged or dirty the timing chain will easily jump and set that exact fault.he said he sees one like this at least twice a month
Maynard- Im not clear on what youre asking. In the first part of your thread you said 5v and ground are both present. In the 2nd part you say voltage is 0 unplugged or plugged in. Clarify this. Also what service information are you using?
This is an update: the executive decision was made to install a new pcm, after installation we had the same scenario, and now we were able to test, The new pcm also did not have a pullup to 5V. I tested again open circuit and there was about 100mV on the circuits... basically 0volts. Now the car is gone again. It was brought in asking for us to program a new pcm for this issue. We held them off…
I spoke to another Nissan tech 1/2 hour ago he said car will still run and drive with no cam sensor activity it will only exhibit a hard start.but he said if timing chain jumped to the point of more than 20 degrees of cam deviation,the ECM will switch off or delete the cam sensors to protect the engine.