4l60e - wont shift, 1st gear only
Checked the VSS, puts out volts when I turn the wheels, TPS is brand new and has 5V. I have not used a transmission scanner yet.
Either my harness is not doing the job or i think it could be caused by faulty grounds thru the PCM. My pressure is also high at about 210psi in park. Doesn't change as I increase RPM. Since most of the electronics in the tranny rely on a ground, it would make sense it is not grounding well enough. I can figure out how to ground it any better. I have seperate grounds running to the engine block. The block is grounded with a thick strap to the frame.
Has anyone had an issue with a bad ground really affecting shift performance?
Also, I made my own stand alone harness from the original. I thought I could save $700, but I just ordered the P/N 60508 Painless Harness.
If the harness does not change anything, I will have to bring the car to a transmission shop.
So far, I think you just have a major electrical/harness problem. Since you have 1st gear, reverse and 3rd gear (via limp mode) the trans is likely mechanically sound.
Stuck is 1st gear could be a wiring harness pin mixup.
Also, 210psi in Park is very high, indicating that the circuit to the PCS (also called EPS) is disconnected, which then maxes the pressure. Also likely a wiring harness pin mixup.
Also, my transmission guy (very old school) thinks it's because I grounded out my NSS and the computer doesn't know what gear I'm in. I thought the NSS is just a safety switch and the pressure manifold in the trans tells the computer what gear it is in. His old school approach makes me hesitant to bring him the car. I might
Need a new transmission guy.
I'm also wIting for my cousin who has a transmission scanner to come over and see what the transmission thinks it's doing but idk when that will be.
http://www.msgpio.com/manuals/mshift/wiring.html
Note that it appears the pressure switch uses the case as ground. Thinking about that, it does sound like you might have a grounding problem.
Just run the ground wire to any bolt on the trans case.
http://www.msgpio.com/manuals/mshift/wiring.html
Note that it appears the pressure switch uses the case as ground. Thinking about that, it does sound like you might have a grounding problem.
Just run the ground wire to any bolt on the trans case.
I have the same exact problem that you have described with with you car. Did you ever find out what it was? Was it the ground wire? I have tested every wire in my harness 3 or 4 times and I'm hunting for the right answer. I have replaced the pressure sensor plate inside the tranny, tested the the tranny harness, good, solenoid, fuses all good, any real help would be awesome.
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Now that you have made your first post, why not start your own thread and describe exactly what symptoms you have. Your symptoms might be a little different and that the make a huge difference in the diagnosis.
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