Engine runs with the cam sensor unplugged, and trips code se2703-03 high V. Plugged in the Cam sensor and engine will not start. If the sensor is bad, why will it start with it unplugged??? Thanks in advance
This is a 2013 EC240cl with Deutz engine Serial #VCE240CV00110691
Still haven't received any input on the cam sensor recently. I replaced the sensor, but still it will only start with the sensor unplugged. It will however continue to run when I plug the cam sensor in once it is running. When I plug it in while it is running I receive an additional code of 2703-8 and still have the original code of 2703-3 Anyone out there with an idea as to what this problem is? Only codes that end that I can find refer to an erratic signal. Any ideas are greatly appreciated. Thanks in advance
I wonder if the erratic signal means that the cam gear is moving too far from the sensor and the erratic signal makes it not start. There may also be a crank sensor that it is using as a second reference point.
Remove your valve cover and watch the rocker arms closest to flywheel. There was an oiling problem in some deutz engines where the last cam follower would starve for oil and begin to disintegrate. Check sensor tip for accumulated metal fretting.
There is a crank sensor in the front of the engine. When I unplug it the engine will not start, so I am assuming it is working properly. The head may have been changed before I bought it, because there appears to be a vent hose at the rear of the head that conflicts with the knock sensor and both will not hook up at the same time. Only one or the other. When I pulled the old cam sensor out, there was no metal fillings around it. I'm wondering if the timing could be off a tooth, but it runs very well when cam sensor is not connected. Has me stumpted!
The knock sensor you described is more than likely the egr solenoid. The cam sensor should be in the flywheel housing. Please attach a pic of what you're looking at.
Yes, the cam sensor is just above the starter on the flywheel housing. Trying to upload a pic of the EGR solenoid and it doesn't want to be viewable, but that' s prob what it is.
If pics are too big, use your phone to screenshot you pic. It will be smaller and have the right attachment suffix.
View attachment 245747
Thats the cam sensor I replaced. I don't think the original was bad. And that is the EGR which does not fit where it should go
So, someone has been cobbling **** together. You want the valve cover with a large round breather valve in the back, i believe. The C models were offered with common rail like you have but a different configuration. Im wondering if your harness isn't incorrect or have a pin out of place.
Thanks, I will start looking for the proper cover and hope it's just a wire problem
Do you have schematics. I currently don't have access, but some of the other guys do.
I do not have schematics. If someone has them, I would be very appreciative if they would share them with me. It's very possible it could be a shorted circuit somewhere. The backup beeper was beeping yesterday with ignition off, so I thinking it's running current through the frame somewhere, or a hot wire shorted to ground. Had to disconnect the beeper to keep battery from draining.
If you have a oscilloscope it would help to determine your issue. But these should help you just as well. Good luck and I hope its a simple fix.
By the way you dont need a expensive oscilloscope. Amazon has one that you use with your laptop for a reasonable price.
So, before we get further down the rabbit hole. Do you have your fuse and relay housing in the cabinet immediately behind the cab? The schematic provided is for late model with tier 3 engine. The earlier models would have different connectors and connection identifiers.
Is there another way to run the tests without the breakout harness. I don't have one
The testing provided shows the value you should see. The pinout will be the same. You are verifying the integrity of the wiring from the ecu out to the sensor. The resistance of the sensor, and whether or not either of the wires are grounded or open.
OK I can work with that Thanks I'll let you know how it goes
YES, fuse cabinet is right behind the cab. I traced the wires back from the cam sensor This is not making sense to me. The wires from the Cam sensor are hard bundled (3) Yellow and two black in one jacket. They go directly to the crank sensor. There are no other wires coming from either sensor. Plug them together and the engine won't start. It will start with the Cam sensor unplugged from the Crank sensor and run good. Unplug the Crank sensor and the engine will not start. Where is the ECU getting is reference from if the Crank sensor and Cam sensor only connect to each other? No other wires coming from either. The wires to the Cam sensor only have .19 V to the sensor with the ignition on
So at the engine ecu connector EA pin 45 and 46 is there continuity with the cam sensor unplugged? Is there continuity to ground? Please check. It seems you're close to finding the problem.
Having trouble finding the wires at the ECU. Two gigantic plugs with huge bundles of wires. Wires at the sensors are three wire, not two. Yellow and two black. I'm assuming that's the ECU behind the fuse box with two big plug connections on it
I'm not quite following what you're saying. From the schematic they are both on their own circuit. SE2703 which is the sensor on the flywheel shows to come from pin location EA46 at the ecm. And pin location #2 at the sensor harness which is the brown and white wire on the engine harness side. The yellow wire is pin location EA45 at the ecm and pin #1 at the sensor harness. I don't see where they are connected to each other. Does any of those wires have continuity from ecm to where it plugs into the sensor. Or shorted to ground or voltage. I believe that your engine ecm is next to the fuse panel. One connection will be EA and the other EB.
Look for connector CNED which should be a square large connector up near the FCV . It should be mounted in a tin bracket with a torx or alan screw holding together. A twisted pair can rub through each other in the wraps. Once you've identified where the short is, you can go after it or run a separate circuit outside of the loom. When measuring, if shorted to itself, disconnect CNED. If short goes open, measuring at conn EA, you know the problem lies in the engine harness. Then you would measure from CNED 13 to CNED15.
OK. I am about to fire up the laptop and look for a different schematic. I wasn't prompted for a serial number break when looking up these files.
You have the right one Paul. It's all good. He has a short
Where does the wires head back to the ECU They only go from one sensor to the other, unless I'm missing something
If you disconnect the harness from the ecm and look on the side going into the ecm. There are numbers at the end of the rows. For example one row would have a #1 and at the other end #15. So that row would count down the line 1-15. That's how you can find pin EA45 and EA46.
Got it, I'm headed back out there
I had no continuity between 45 or 46 at the ECM and Cam sensor harness connector. When probed with a power probe, at the Cam sensor connector with key off, I had no ground and residual static buzzing at the Yellow wire and one of the black wires. I also checked the Cam end of the harness to the Crank sensor end for continuity between the two ends of the harness, with nothing. I did that because it appears the two are connected by the solid 3 wire hard molded wire harness. Yellow and two black molded together
Are you perhaps describing a shield wire or shielding jacket. Twisted pairs often have a 3rd wire wrapping the pair or a foil jacket wrapping the pair to shield RFI from affecting other circuits. Can you attach a pic or 2? Again...
these are 3 wire sensors, with 3 pins, both the cam and crank
See if this makes more sense.
You're still looking at 2701 & 2703. Cam is 03 crank is 01. EA5 should be ground and common to pin 3 of each sensor. There should be no continuity to pin 1 or 2 of either sensor. Pin 1 to pin 2 should measure approximately 3900 ohms. This rectangular connector should be buddied up with another in the same housing. EA is on top EB is on bottom. EB us where the harness comes out of the housing. I believe you will have this big round cannon plug for engine harness to the machine. Please see the attachment The sensor should ohm out at 3.9k ohm.
I couldn't read the pic 16326066178618373103
nevermind that the schematic says it is for a 160, it is the same up until 330 where the begin using big bore engines. All the deutz in lighter machines are looking for the same values. What matters is that you get the right configuration. Can you upload an away pic of your engine so we can see what fuel system you have. It seems like you have a tier 3 machine with a tier 2 engine. Just trying to get you the best possible info.
by the way , did you click on the pic to blow it up in another window?
Also have this loose wire with no place to go. We also have the wrong valve cover on this it appears because it will not allow the EGR solenoid to mount
Those came through great Thank You. Loose wire is blue wire 7.9V and white with maybe black tracer-ground
I am totally lost. When you check for continuity from the sensor connector back to the ecm. What pin location are they going to? Are they indeed going back to EA45 and 46? Or are they going to another pin location. I'm wit FWF on this. Sounds like the right engine but wrong application.
When I checked for continuity, battery off, key off, Top rectangular connector at ECU. Numbers go four in a row, 41-44, then 45-48, then 49-52 I checked continuity from all three connections at the harness end where cam sensor would connect, back to 45, then 46. There was no continuity to either wire
I will check continuity tomorrow for all pin locations 1-56 and see what comes up.
OK. Where the engine harness connects to the speed sensors. Is there a third wire in the engine harness at the sensor connector? And if so where does that wire pin at ecm? At this point I am not sure how your engine is running but I am confident that we can figure this out.
Dumb question here. Are the sensors themselves 3 wire?
Yes these have 3 pin connectors at the cam sensor and the crank sensor
FWF can probably help understand this conundrum better than I. He has been working on these a lot longer than I have. And he would know all of the idiosyncrasies of Volvo's over engineering better than I. I am wondering if you were to isolate that third wire that is seemingly tied to both sensors. That it would solve your problem.
Keep in mind that if the cam sensor is plugged in, it will not start, but if unplugged it starts and runs great. If I plug the cam sensor in once it is running it continues to run, but trips a second code 2703-08. Once shut off it will not start again until cam sensor is unplugged.
Thanks for all the time your spending on this. I'm lost without you guys )
These engines are designed to run with just one crank/cam position sensor. My thinking is that you have a engine from another serial number break or machine altogether. And it just so happens that 4 of those wires are pinned the same as the original engine harness. And I am also thinking that these sensors will work with just two wires. And that when both are plugged in then that third wire is causing a issue. That is why I am curious to where that third wire winds up at the ecm. It may be getting voltage and causing issues with the sensors. Did you say that the cam position sensor was new? I can't remember. And you are welcome this is what this forum is for. There is a ton of knowledge and experience here and some of the nicest people that are willing to share that knowledge and experience.
Let's get back to a starting point. ECU and sensors disconnected. A)From cam sensor pin 3 to crank sensor pin 3 we want to see less than 1 ohm. Now from pin 3 of either sensor to pin 1 and pin 2 of each sensor. There must be infinite resistance. This is measuring the shielding ground against the 2 sensor circuits for cross bleed. B) from pin 1 to pin 2 of each sensor connector of the harness. There should be no continuity. It must be an open circuit. Now measure from Connector EA pin 30 to pin 1 of SE2701. You're looking for less than 1 ohm. Measure from Connector EA pin 31 to pin 2 of SE2701. You should again have less than 1 ohm. Look at sch 18 posted in reply #40. Additionally look at passive measuring for 128 . This is measuring resistance values at the engine ecu connector of solenoids and sensors. The values you want to see are shown. Write down your results, take pics of results, we'll get through this, you just might not have all your hair.
Eng won't start plugged in cuz it's getting a crap signal. Take away the crap signal and the computer figures out if its coming up on 1 or 6. It bases everything off that reference vs the missing cam. It will run off one or the other but it must have 1. Cam signal is more refined since the wheel is moving at half crankshaft. Running off crank only, fuel isn't optimized to the level that Volvo wants. She'll still dig smooth and everything else she's asked to do.
I'm going to sit back from this to keep the confusion down to a minimum. If you guys need different technical material then let me know and I will get it to you.
This is a Deutz engine. The cam gear is in the flywheel housing. Not the larger bore Volvo engine. Welcome to the forums. Have you stopped by new member introductions yet?
Using a second person up on top and me at ECM. I do have continuity at pin 45, and 46. Pulling the big square plug apart on the metal bracket where wires connect to ECM harness, ground wire connects to a blank plugged pin. No continuity from third wire to pin #5. Cam sensor is in the housing just above the starter. Sorry for the continuity mistake. You spent a lot of time because of that. Yes it is a new Cam sensor
Pin 45 to pin 46, how many ohms? More importantly pin 37 to 38 how many ohms? With or without cam sensor plugged in? And which schematic are you using? 03 or 18?
Without cam sensor plugged in, from the cam harness to ECM O ohms at pin 45, and 46. After unwrapping the harness, Cam sensor and Crank sensor are not connected, but on separate shielded wires to the ECM harness. At the Cam sensor there is no continuity from pin 3 to either pin 1 or 2. A. There is no continuity of any pins between the two sensor connectors. They have separate shielded jackets. B. from pin 1 to 2 of each sensor connector, there is no continuity
I measured resistance on the Crank sensor harness to ECU. Center wire (yellow) was .6 ohms on pin EA37. Resistance on EA 38 to outside connector was 2.0 0hms. I am assuming that would be 2 on sch03. When you look at the 3 pin connector with wire lock on top, it is the left of center wire.
So unplugged at sensor and ECU you have 2 ohms between 37 & 38?
Unplugged at crank sensor and ECU, I have 2.0 ohms between yellow center wire on the sensor end of harness to pin EA38 at the ECU end of harness. I had .6 ohms on the other wire left side of unplugged crank sensor harness that goes to EA37 on the ECU end of harness
I did not check resistance from EA37 to EA38 with crank sensor plugged in. Is that a reading we want?
Im struggling to understand. Are you measuring circuits individually end to end or measuring for cross-bleed at one of the connectors?
I just measured continuity from crank sensor end of harness where it would plug into the crank sensor, to ECU end of harness individually, one wire at a time
So measuring end to end you have .6 ohms on one and 2 ohms on the other? 2 ohms, not .2 ohms? But pin to pin, you have open circuit correct?
I would think those wires should have 0 resistance, similar to the wires for the cam sensor
I did not measure pin to pin with sensor unplugged. I will in the morning. I was just surprised to see 2.0 ohms to EA38
Yes, 2 is very high, you may have to run a new twisted pair. Not the end of the world.
I will check Crank sensor shielded wires end to end to see if the resistance is there or in the ECU harness
There is no continuity from EA37-EA38 with ECM unplugged and Crank sensor unplugged. There is also no continuity from EA45-EA46. No bleed through
But you still have 2 ohms on one leg. Are you measuring through the bulkhead connector?
I measured through the shielded wires through to the ECU I can disconnect the block connector at the rear of engine and check from there to the ECU to eliminate the shielded wire.
Well. it would be nice if you could narrow it down to one side or the other. Ideally you want less than 1 ohm, total circuit. Higher than one tells me a broken wire or corroded terminal. Something along those lines.
Well, this is not exactly the ideal readings, but from each end of the crank sensor harness through the shielded wires, I read .3 ohms on both wires. From the ECU harness I measured from pin EA37 to the other end of that harness where it buddies to the big square connector, and read .9 ohms. I read also .9 ohms measuring EA38 to it's corresponding pin in that block connector. Both ECU end and block at other end od ECU harness were unplugged
While not ideal, they are fair. No open circuit. No short circuits. Which only leaves the sensor itself. Have you confirmed that the new sensor is in fact good?
The dealer is going to send us another new one to check it
FWF, Correct me if I'm wrong,but I seem to remember that there are two types of speed sensors for that engine. I'm about to fire up the laptop to confirm that. Since you have so much more intimate knowledge with Volvo than I. I thought you would know the answer.
I see two part numbers. It looks like it started as a 20820494 and changed to a 22435058.
Yes. 2 wire and 3 wire. That's what threw me when he kept mentioning a 3rd wire. I thought we would be dealing with the 2 wire since your schematic (which is correct for B series tier 3) showed only 2 wires. That was the head scratcher.
But have you measured the sensor for the correct resistance? Approximately 3900 ohms per test procedure.
I will test it in the morning, and also test the original one. I'm not sure the original one was bad. There is a short somewhere in the electrical system, because the backup alarm will chirp weakly even with the key off. we unplugged it to keep the batteries from draining. I have no Idea where to start tracking that, but could it effect the cam signal?
I also never found a code description for SE2703-08 which is what I get if I start the engine and while it's running I plug the cam sensor in. It will continue to run but trips that code
here you go. I thought I included that.
I checked the old cam sensor off the vehicle, and ohms read 3.6K ohms. I checked the currently installed cam sensor in the engine and it measured 3.9K ohms.
The error sheet you sent makes reference to possible incorrect distance from the sensor gear. How would this be measured? It's almost impossible to even get to the hole the sensor goes into. It seems this is the direction I have to go next
Ones perfect. The other is close. Post 24, you stated that you had .2 volts going to cam sensor. You shouldn't have any. Please find source of unwanted voltage. That's most likely causing your corrupt cam signal
I think it's time to get a oscilloscope and see what is going on with the frequency. As far as I know there is no adjustment to be made for distance of speed sensor. https://www.amazon.com/Automotive-D...cilloscope&qid=1632951327&sprefix=hant&sr=8-4
I agree Paul, but he's never negated the .2volts he saw going to the sensor. That would definitely prevent the ECU from seeing #1 since it would never find 0 on the wave form.
Doesn't the sensor need some voltage to return a signal to the ECM? I will be checking tomorrow also to find the bleed in voltage that allows the backup beeper to give a low pitched squawk with the key off. Somewhere I have a short traveling through. The backup alarm is on the other side of the engine, but if the short is close enough, maybe it could disrupt the signal
Look for ground faults and failed diodes. On the bottom of the fuse panel. The short grey/black fuse looking things are quenching diodes. If they are in backwards or shorted, they can cause all kinds of whacky behavior. Also, take a sniff inside the fuse box. Be honest with yourself, does anything smell burnt? The earlier ones were prone to failure from water intrusion.
No, the sensor is generating its own square sine wave with the windows of the cam gear. Any voltage on the line, whether ac or dc will corrupt the pure signal generated by the sensor.
Rechecked for voltage to cam sensor. I separated all the wires in the engine harness where thry plug into the ECU harness to separate the Cam and Crank shielded wires. I only measured .003V at the square end of harness near engine, on the EA 45-EA46 wires when harness was plugged into ECU with key off and Battery switch on. How would I check if the quenching diodes are shorted? Are they marked directional?
Yes, they're marked. There's an image on the bottom of the fuse box cover, match it up with the image on the diodes. .003v is negligible, .2v is not. Have you tried checking for errors since splitting the wires apart?
I did attempt to start the engine with both sensors plugged in, and no start. Again starts with only Crank sensor plugged in. Same error code when ignition is turned on. SE2703-03.
Have you visually inspected the gear that the cam sensor reads from?
There is a wire that has been added to the fuse box which goes from the hot wire terminal on right side of fuse box to the Ignition switch in the cab. The ignition fuse was still in it's proper position and not blown. I removed that fuse and engine still starts and runs. There must have been a short in this circuit at one time. Removal of the fuse didn't change the error code
I have not inspected the Cam gear. I have a camera that I might be able to worm down to the Cam sensor hole. Its pretty much not viewable any other way other than removing the Pump and flywheel.
This is what I use. It is very handy and works well. https://www.amazon.com/DEPSTECH-Wat...33280228&sprefix=inspection+camera+dep&sr=8-3
I have a scope very similar Should work. I will look for ships or broken teeth.
I traced the wires again today, pulled the cam sensor out and viewed the tone wheel. I cannot see anything abnormal there. While testing the wires to the cam sensor again, from the large square connector for where the engine harness connects to the ECM harness, I tested for ground and cannot find where the sensor can get it's ground from. The ground wire is all good going into the large square harness connector, but lines up with a blank white plug on the ECU side of that square connector. There is a grounded pin right beside the ungrounded wire. Am I making sense or am I confusing everyone. I don't believe I have a ground for the Cam sensor unless there is a common ground I'm not finding. I have no continuity to ground and no ground that lines up with that ground wire.
Its a shielding wire. Sometimes grounded, sometimes not. Its only purpose, squash RFI on the signal wires.
So the three wire connector going to the sensor is supposed to connect to nothing going to the ECM for ground. Is that correct? There is no continuity to ground on that wire
That's acceptable. Refer to passive measuring that was attached as well as the schematics provided. You're only concerned if there is a cross-bleed between 1,2 & 3 with the ECU disconnected. Additionally, you don't want any continuity to any other pin as they are completely independent of all other circuits. Any continuity outside of the sensor itself must be eliminated.
So far everything checks out OK, just still a problem. Might have to have Volvo field service put the computer on it
Did you ever get another speed sensor? I remember you saying that you were, but don't recall you mentioning anything about it since.
Well, I had to resort to getting field service out there. He verified everything we checked. Signal was good all the way to the ECU at different RPMs. Going to have to find a good ECU Thanks Paul and FWF for all the assistance and time spent helping me.
Well, after field service condemned the ECU and waiting for a long time for them to get a new one, it did not cure the problem of the engine will not run with the cam sensor plugged in. Field service spent 6 hours there yesterday with no change. We have determined that the engine has been changed but there is no serial number tag on it. The cam sensor for the original engine should plug into the bell housing from the rear. This engine in it has the hole for the cam sensor in the block facing rearward. This he is saying is reading the cam signal different from what the ECU is looking for. What I need is to figure out what engines that look identical to the original would have had the sensor facing rearward into the block. I will have to change the rear housing and cam gears inside to make it right. Any knowledge out there is greatly appreciated. Thanks Mike
Heres 2 harness configurations. One for your machine, one for an L90F loader. Notice how one has an EGR solenoid and the other does not. Hope this helps you
Even though ithe diagrams don't show the position of the cam sensors, it looks like the harness for the L90F with D6E engine goes to the forward side of the flywheel housing and the original engine for the EC240cl goes to the rearward side. Is this correct? The question is, if the engine and flywheel housing were changed as a running engine, why would the cam and crank sensor now be out of sequence? Does the ECU read a different number of cam pulses per revolution for this engine and not like it? If that's the situation, it may be really hard to find a flywheel housing for a ec240cl with a hole in the rear side for the cam sensor. The assumption by field service is that the valve cover is incorrect for the motor. He said hook up the EGR solenoid and let the hose vent to the atmosphere.
Did the dealer tech do a vehicle information test? Is the ECU for your excavator or for another machine? It shouldn't run with anything but an excavator ECU. #1/6 are the same no matter what. In fact, you showed a pic with cam sensor for your engine, facing fwd. We've already established that either the head or engine have been swapped. We saw that looking at the valve cover and relation to EGR solenoid. This is gonna require some serious digging. I'll be back online this evening, we'll see what we can come up with.
ECU is original from what we could tell. Rep programed the new ECU from the old one manually with no effect in codes or running conditions. At least he took the new one back with him and not charging us for it. The engine has a cam sensor that faces rearward. Rep says the correct original engine should have the cam sensor facing forward. We will need the correct flywheel housing and cam timing gears to fix this problem. (He thinks) It appears that whoever replaced the engine has replaced everything after the hyd pump forward as a unit. including the flywheel housing and cam timing gears. It probably ran fine in whatever unit it came out of if the ECU matched the engine. The valve cover on this engine does not match the engine it is on also. They possibly could have damaged the correct cover during the exchange. The valve cover is a minor problem, but doesn't make a lot of sense where it came from.