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Hiya people. I'm scratching my head on one here trying to help the guy who works next to me. Car came in as a no start. TCM is not communicating at all. U1000 codes from other modules and TCM is not showing up on a full system scan. Our factory scan tool also says that it's offline. No range display on the dash, which is why we think it's not starting, it doesn't know it's in park. There are two powers and two grounds at the TCM, and all four check out ok. There is 60 ohms on the can lines, so those should be ok. A new module didn't change any thing. Thinking out loud now, maybe it's a pin fit issue at one of those four connections on the harness? After you install the new TCM, you are just supposed to turn on the ignition, then turn it off for 20+ seconds for the cvt solenoids to initialize with the new module. You know that is complete when you get a P indicator in the range display. That is not happening. Any other ideas before I point him to a pin fit test?
Test was done with KOEO, backprobing the harness at the TCM with a dvom with one lead on battery neg. Subtracting power results from battery voltage reading. Ground circuits had 4mV if I remember correctly and the power side drop was also only a few mV.
Before you swapped the module did you pull each module offline as with the U1000 if I recall that's a network error code? Just going off of memory here so I'm winging it.
I'm more concerned to why a tcm was thrown at it when you should verify the network.
Paul has a video of this is if I recall and Eric O has one as well as I've seen it over there somewhere.
IF you have all the modules offline and have the tcm communication then you need to add each network back individually until you get your error back then you will have identified the network causing the problems.
This is something I know I've read about and seen actual video footage on. I just wish I knew exactly where.
Trained by techs YouTube could be a possibility as well on the video regarding this issue
This module doesn't need programming after installation. It just needs to know the solenoid memory, which happens with that key on/off procedure.
Can you elaborate on "testing the network?" Communication is possible with all other modules. Consult 3+ (the factory scan tool) has function tests for the network and it showed that the TCM was only module with no communication. The can lines have the proper 60ohm resistance.
I know what you mean when you have an ECU no comm and a sensor is bringing down everything when you don't have 5v ref. In that situation, you would start unplugging them until you get 5v ref back. I don't know that this is that situation though, but I could be wrong.
I wouldn't say he just threw a part at it. I know that he spent quite a bit of time trying to determine the problem and with the available resources, this seemed pretty logical.
Only other things I can think of are if you had the aes terminal kit just run jumper wires from vehicle harness to tcm terminals for power ground com lines and remove all outputs just Incase one is causing the no communication problem. Or if you missed a power or ground. You work at Nissan could try another one
Yea, they are refering to bringing back each module individually until the confirmed "problem" module is found. This is similar to the older GMs with sp206...pull the comb, and communicate with each module. Not that you have a comb...just an example.
Tutti57 wrote: This module doesn't need programming after installation. It just needs to know the solenoid memory, which happens with that key on/off procedure.
Can you elaborate on "testing the network?" Communication is possible with all other modules. Consult 3+ (the factory scan tool) has function tests for the network and it showed that the TCM was only module with no communication. The can lines have the proper 60ohm resistance.
I know what you mean when you have an ECU no comm and a sensor is bringing down everything when you don't have 5v ref. In that situation, you would start unplugging them until you get 5v ref back. I don't know that this is that situation though, but I could be wrong.
I wouldn't say he just threw a part at it. I know that he spent quite a bit of time trying to determine the problem and with the available resources, this seemed pretty logical.
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Well if the factory scan tool has all that function then you've got me beat.
What I was referring to was that verifying with something such as a breakout box by checking the individual CAN lines for activity. IF you have a a scope you can do this.
You've got me on the exact procedure as I recall seeing it done a couple times. I think Paul aka scannerdanner has did it and if not I seen it performed in a video or somewhere.
I learn alot watching online paid and youtube but don't always use that information right away so some of it tends to go the byway until the issue comes up then I have to look it up again. I'll try to dig quick and see what I can find on it.
Here's one way but as you said you have the 60 ohms per line so you're good on that part. Just remember this so in the future if you don't have access to a factory tool due to it being down.
Thanks. That is a good video. I'm going to be back on this car in the morning. I'm going to open a case with our tech line in the morning and see if they have any suggestions. I'll post back when I get more info.
Ok, I got it figure out, kind of. I'm still not 100% sure what happened, but the car is running.
I checked all of the powers and grounds like 3 more times, ran a fat jumper from bat neg to the cvt case, added bat neg to the TCM harness, nothing. For the heck of it, started tracing power on the range selector switch and found power going in, but not coming out on the park side. The switch is a pain to get to on these, under the battery tray, so I took that all out and put two t pins in the switch with jumper wires and also added my dvom to make sure it was all connected after I cobbled it all together with the battery on top. Now I have no power there at all. Checked the fuses and found a blown one. Replaced the fuse, and everything was back online. Odd thing is that when I remove the jumper setup, everything still works fine. I don't know what happened, but I know for a fact that fuse was in tact before because it supplies power to other locations that I also had power at. Only thing I can think of is that the t pins helped a bad fit. Oh, well. It's working now.
