91 marathon problem with reverse on wireing

[WILD1]

First Post, bare with me. Sorry for long post trying to give as much detail as can.
Cart: 91 Marathon, 36vlt, 500amp altrax, heavy duty solenoid, heavy duty F&R switch just replaced, Just replaced Pot Box.

Problem: switch into forward everything works as should, switch into reverse, get 1 green light flash on led on controller then goes to 1 red flash, and will not engage axle, does click on solenoid.

I called altrax before changing potbox out today and tech said buy radio shack pot and see if controller works then. I did and hooked up only black and white wire to controller thru the pot. and left all other switches and wire connected, worked fine by adjusting pot.. So not controller, I assumed pot box and just installed new one today and it still does same thing.
I have tested everything I can think of, traced wireing 1500 times.

I am STUMPED! Any help appreciated.
First post but been in shadows reading, that is how I built this cart for my 74 yr old mother.

[WILD1]

Problem solved. Butting head against wall really does help.
Problem was when replaced fnr switch to heavy duty there was only 1 micro switch on driver side verses 2 so I assumed (yes I know what that means, maybe not so much u) the white battery wire to the backup beeper for power went to the micro switch still and had it back feeding power back thru pot.. Removed and works like it should except just don't have backup beeper.
Excess parts I guess.lol
anyone know how to hook backup beeper up on just two microswitches where it does not work on forward and reverse?

[JohnnieB]

The Marathons that used the F/R assembly with three microswitches did things a little differently than the later series drive carts the only had two microswitches on the F/R.

One of the double microswitch pair turned on the beeper, which ran on 6V.
The other one, put a fixed 5K resistor in parallel with the 0-5K pot-box, so the controller only saw 0-2.5K in reverse (1/2 speed).

Later models had one microswitch instead of two and when in reverse, it fed 36V to a 36V beeper and fed 36V to a pin on the controller that told the controller to only run at half speed.

Get a 36V beeper and wire the two microswitches on the new F/R assembly as shown on the schematic from Alltrax and it will work.

[WILD1]

Thanks Johnnie b