Hello, I don't know if this is a place I can ask this question. If not please tell me where to post this question please.
If I am at the right place please help me.
have few questions.
1_My present situation.
*I'm trying to do an ENGINE DYNO VEHICLE EMISSION TEST.
*The ECM I am going to use is not from the vehicle which will be tested. I have an other ECM just for testing from the same vehicle model.
*Once the engine is installed on the dyno bench for the engine dyno test and check for DTC I have Crankshaft Position System Variation Not Learned(P0315) & Lost Communication With Body Control Module(U0140).
*When I try to do the Crankshaft Position System Variation relearn, it won't work.
2_ My questions.
1) Is there no problem for the test even I don't do the Crankshaft Position System Variation relearn?
2) I think that the Crankshaft Position System Variation relearn can't be performed because of the Lost Communication With Body Control Module(U0140) DTC. Is that correct?
3) Is there no problem for the test even if I have Lost Communication With Body Control Module(U0140) DTC ?
It depends if this engine for a canoe or not.
In case it's not for a canoe...
We need way more info. Where are you? CA is way different on emissions testing than OH vehicle model and year? Donor engine model and year?
In reply to Patientzero :
sorry... I have no knowledge in this area... What do you mean by "engine for canoe"?
In reply to Curtis73 (Forum Supporter) :
more information as you asked :
CA emission standards
vehicle model : Chevrolet Express Van 4500 cutaway
year : 2019
engine model : 6.0L V8 L96
And I have an extra question.
For the engine dyno vehicle emission test I don't have the BCM.
There is only the ECU and Chassis control module(don't remember the exact name... sorry) connected to the engine.
question:
1_ Can the Crankshaft Position System Variation Not Learned(P0315) DTC pop up because the ECU is not reading the BCM?
It sounds like you need to have VATS disabled. Since the ECU can't communicate with the BCM it won't start. It's an anti-theft feature.
Disregard the canoe comment.
Agreed. Getting one ECM to play well with a different VIN is probably your problem. In order to switch ECMs, it will need to be reprogrammed with the information from the van.
The way I understand it, the BCM handles the security features and signals the ECM to let the engine operate. One of the anti-theft features is that the VINs have to match. Otherwise, you could steal a van by putting a new ECM in it to fool the BCM into letting you hotwire it and drive it away. To combat that, the ECM and BCM are programmed with the VIN (or a code that is unique to that VIN). If they can't agree that it's the same VIN, you'll have communication errors.
In the 90s, you would be fine. You get one ECM and no BCM, and the VATS is a dummy resistor in the key that completes the fuel pump circuit in the ECM. No fancy communication to worry about. In a 2019, it has to be matched to the vehicle by programming it.
Your crankshaft issue might be because LS engines use two different crank reluctors and two different cam reluctors. 58 tooth or 24 tooth on the crank and either 1 or 4 teeth on the cam. Then they also use a few different cam and crank sensors. It's possible your ECM is looking for the wrong signal.
Take a look at this page. You'll see all the possible combinations. It looks like this website only lists up to 2014, but you can see why it gets hairy.
Is this a chassis cert or dyno cert version? If it's under 10k ETW, it's a chassis cert, for sure, if it's over, it could be either chassis or dyno cert.
And it sounds like you are running this on a dyno only set up? So a transient capable dyno?
The crank profile issue has nothing to do with the body module- it's just a system to make sure the cam and crank patterns are set correctly to make sure it can properly identify a misfire. Ford has a specific procedure to run (which I can't recall) and I'm betting GM has a similar thing to do. Maybe look up "profile correction for GM" on google or something like that.
In terms of needing the BCM, is it safe to think it does not run? Depending on what dyno set up you are doing, you may need to find your donor BCM. Or find a calibration tool to ignore that anti-theft system.
In terms of the testing- as long as it runs, the BCM isn't needed. And I don't think the profile correct problem will be a problem, either- I've run plenty of tests w/o the profile correct run, and it will eventually learn.
Since you have the specific model, once you start getting emissions data, you can compare that to the certified data that is on the EPA database.
In reply to Patientzero :
I think I didn't give enough information.
The engine is already hooked up on the dyno.It's cranks and runs. The VAT has been disabled.
Thank you for the detailed information. I will need some time to understand exactly what you told me. I will be back to you if I have more questions.
In reply to alfadriver (Forum Supporter) :
Yes! I think it's called as you said a dyno only setup because we just have the engine hooked up to the dyno and we have the ECM, fuel tank and Chassis Control Module(not sure for the last module name.) connected to the engine. Nothing else is connected.
And it's a transient capable dyno because I am trying to do a engine dyno vehicle emission test by EURO6 WHTC (World Harmonized Transient Cycle).
The VAT has also been disabled. We were able to check the maximum output of the engine that GM has mentioned. (I don't know why but the lab had to test if the engine could reach his maximum capacity "xxx HP @ xxx RPM and xxx torque @ xxx rpm" before doing the test)
My following questions might have already been answered but I'm asking one more time just to make sure.
Questions:
We have two DTC. Crankshaft Position System Variation Not Learned(P0315) & Lost Communication With Body Control Module(U0140).
1_ If I understood correctly the U0140 DTC won't affect the emission test. Am I correct?
2_ If we don't do the crankshaft position system variation relearn to clear the P0315 DTC can this affect the emission test? Or can we just ignore the DTC and proceed with the test?
3_ If we have to do the CKP relearn because it affects the emission result :
The Crankshaft Position System Variation relearn wasn't able to be performed even if all other condition required Met. I saw on google that any other DTC except for the P0315 has to be cleared to be able to perform the relearn and while trying the relearn we had the "Lost Communication With Body Control Module(U0140) DTC". Is the U0140 the reason of the relearn not performed correctly ?
In reply to enginedynonoob :
I'm not a GM person, but I would be shocked that the BCM is needed to run profile correction.
If you can run the cycle, run it. And to debug it, since there is data available to compare to I'd suggest running an FTP75 test- so you can compare what your engine is doing to what GM certified to to be able to do. That data is available on the EPA certification database.
As for programming the VIN, if it's anything like a Ford, you need to get GM's specific tool, so that you can download the previous VIN from the previous ECU, and the re-program it into the new ECU.. Or it can be done manually. For security reasons, that's not a tool that is commonly able to get- since it would make stealing cars when they have a theft system kind of easy to get around.
