545rfe won't shift out of 1st

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retroron

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Just got the car (70 Dart) back from upholstery and went out to alighn the front end. Car won't shift out of 1st gear. Gen3 hemi, 545rfe transmission. Car is fresh, zero miles. Engine and transmission are new, crate package. Thoughts anyone? Car acts like it's in the limp mode. Other problem is I've lost the tach signal. Does the 545 need the RPM signal to shift? Or does the transmission need to be "flashed"?
 
Limp mode would not be 1st gear. Yes it needs to see the RPM signal, find out why and you may find the problem. What codes do you have?
 
Didn't see any codes when they checked at the alignment shop. Im going to checkout again with my analyzer here at home.
 
cam or crank position sensor? Does your speedo work?>
 
My speedo is GPS driven so it doesn't come into play. If the cam or crank sensor were bad it wouldn't run, or run as well as it is. And like I said, there weren't any codes shown at the shop.
 
Has to have the crank sensor to even start. It will start without the cam sensor but will have a long crank time. Neither the cam or crank would have anything to do with the transmission not shifting. The RPM signal is a BUS signal from the PCM to the TCM. Check with your scanner and make sure you have the Turbine speed (transmission input) signal with the engine running.
 
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Also make sure you have B+ from the ASD relay powering up the solenoid pack. If no hard code yet you may have a secondary indicator showing up in the monitors.
 
If it starts out in first gear then defaults to limp in look at the transmission output speed sensor. It will only show a speed count when the vehicle is moving. If nothing while moving from it then that is most likely the problem.
 
I'll see if I can describe the fault better, it launches normal to about 3000 RPM and about 25mph. Then the engine shuts down to idle and I can limp it home. As soon as it faults to idle and I let off the throttle it feels like the transmission free spools. If I wait a second or two I can launch again and repeat. The speedo is GPS so it doesn't come into play.
 
Well, lots of dollars later it turns out the speed sensor was broken, almost in two, thus causing the loss of signal. I couldn't see the broken sensor while laying (or is it lying?) on the garage floor with a drop light. The code gave the transmission shop the clue. Most likely got broken during engine/transmission installation.
 
Well I'm glad I was able to help. Now you can get out and enjoy that bad boy! Have fun... Weather in Ohio isn't so nice for outside car fun right now but it will be in a few weeks! LOL
 
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