96 ego has forward but no reverse does the voltage across b+ and a1 read the same in reverse as well as forward

What Ted said or you can take it to Autozone or Oreillys and they will test it for you for free

My answer is I don't know regarding golf carts but generally a designer would arrange for a solenoid to be actuated by as constant a voltage as possible, especially if it is to be engaged for long periods. That is the only method to ensure consistent operation without danger of overheating. This is assuming the available voltage energises the soleniod.
I would expect the voltage across the main terminals would also be expected to be fairly constant so a predictable consistent performance can be provided over a long life.

You really need to consult a repair manual/wiring diagram. As a complete uninitiated golf cart layman I would expect the main solenoid switch to be switching the battery voltage which would then supply the speed and direction control board. I could be worng though!

It COULD be a shift solenoid.

It COULD be from being over filled.

I also ran across a GM car one time that would only go into reverse but not forward. Dropped the transmission pan and the filter was almost completely plugged. Changed the filter and fluid and all was well from then on.

So it COULD be a dirty filter.

Hope this helps.

Take your digital volt meter. Place meter on the diod setting. Place your probes on each leg. You should read .7 to .2 in the forward position and infinity or high megs in the reverse position. You'll need the data sheet to find out spec.

the transmission is broked down you got to replace it

check the voltage across the battery with engine at 2500rpm it should not exceed 14.7 V then go from their ,If the voltage is too hight then this would cause problems all along the line

I recently tried the DIY service and repair manuals from a website and it actually helped me repair transmission problem in my jcb 3cx site-master. It would'nt move forward or reverse, engine was good both solenoids for forward and reverse worked, but still couldn't diagnose the problem.
I don't have much technical knowledge but I just followed it step-wise, and now it works perfect! covers wiring, codes, diagrams, torque specs, PCV, everything
got it from www.reliable-store.com

It's a 4-head reversable deck where the Forward tracks are arranged across the physical tape surface, front-to-back as follows:

ForwardLeft ReverseRight ForwardRight ReverseLeft

...so it sounds like the Reverse playback heads are engaged at the same time you play Forward, so you would hear those adjacent tracks backward. If you play the tape in the Reverse direction, is the Forward program audible (but backward)?

If so and in otherwise high fidelity, something in the Forward/Reverse head selection may be hosed.

Or, if the out-of-phase tracks are mushy and low volume, the physical tracking of the tape across the heads could be WA-A-A-A-Y bad. That would probably be visible as sideways distortion in the tape path. Shine a high-intensity light on the tape where is passes over the heads, then reverse it while watching where it sets up on the heads. It should be centered on the heads and not change its orientation when reversed. Compare where it tracks in motion with the probable visible wear marks (shiny bars across the heads perpendicular to the travel) where the tape has polished the heads over the years.

Or, the heads are so worn the coils pick up signals from their neighboring tracks.

input shaft in gearbox has failed

Yes, Zener diodes can work both on forward and reverse biasing. The primary difference between a zener diode and the ordinary junction diode is it is designed specifically to operate with a reverse bias voltage that is high enough to cause the the device to breakdown and conduct a high reverse current. Hope this answers your question and provides you with some help. If you need further assistance please let me know.

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