Bad Controller or micro-switch ?
 

I have, as best I can tell, a 1990 Marathon,36V electric ( 3 wheeler). Had it for 10 years and never a problem. Put it away last winter, running fine. This spring went to drive it, it rolled about 20 feet and quit. I had left the charger plugged into it all winter so it could charge as needed. I noticed that if I pressed the accelerator I would hear the solenoid click, at about half position the cart would shudder forward ( same in reverse) then "kick out" and not move. I checked voltage across the batteries and had approx., 38 volts.
Next, I checked each battery individually and found 2 were < 2 volts.
I replaced all 6 batteries with NEW batteries. Still the same problem.
Read online how to check solenoid & did so. "IF" I did it correctly, the solenoid seems to check out OK. "Clicks" in F & R, showed .04 ohms, etc.
Noticed with meter on CL+/BL+ and CR-/BR- , with fully charged batteries, if I step on the GO, key on in forward, voltage drops off to near zero. Let off the pedal and the voltage rises back up.
While it appears the charger is good, when plugged in, the meter shows no Amps, but the charger does not kick off and will run continuously.
Finally, with the charger plugged in, if I turn key on, press go, the cart wants to run, then charger kicks off, let off pedal and charger kicks back on.
Have checked, cleaned and tightened all connections.
Anyone have any ideas and /or if this is indicative of a specific component failure ? Last resort I'll take it to the local cart shop where I bought it. Just hate to if its a simple component I can switch out myself. Thanks.

Re: Bad Controller or micro-switch ?
 

The more I read on this, the more confusing. wondering if it could be an issue with Potentiometer or Contact board also ? I'm sure this is a 1990 Marathon, but how do I know if it has DCS or PDS controls ? My guess is those are on newer carts ?:help:

Re: Bad Controller or micro-switch ?
 

Hi JD
All the Marathons were series drive. Do this - note the pack voltage
Connect meter to battery pack mains, put the meter on the seat so you can read and drive.
Now try to go and tell us what the pack voltage drops to.


There is usually a battery problem if the charger won't shut off

Re: Bad Controller or micro-switch ?
 

Thanks for the reply Scotty.
Did as you instructed and got 36.8V - drops off to 16.0V
Batteries are new

Re: Bad Controller or micro-switch ?
 

okay - 16v is not enough sustained voltage to run the cart. Re-check that all batteries are connected in 'series' (+) to (-) from #1 battery to #6.

If yes, connect the charger and look for the highest voltage reading you get. notice if charger stays at high amps or decreases to 5-7 amps after an hour or so.....

Turn charger off if pack does not reach 44v in 8-10 hours...


Please identify the batteries by make & model

Re: Bad Controller or micro-switch ?
 

A NEW discovery ( and perhaps the problem ? )
While checking the connections AGAIN, I was looking for identifiers on the Controller. I discovered the bottom panel of the controller housing was separated from the housing body. I reached down and pulled it away, to discover it had been taped ( clear packing type tape)on to the housing. This had to have been that way since I bought it and I'm assuming the controller housing is generally a sealed unit ( "No user serviceable parts inside") ?

The cart sits in an unheated shed, with the temperature fluctuations/humidity/moisture to be expected in central Illinois, as well as the occasional washing and moisture from usage on grass.

Just trying to provide any information of possible use in diagnosis.

I plan to order a new battery wire pkg. Looks like I may as well order a new controller as well ?
The old one is a Curtis PMC Mod# 1204-027 24-36V 275A.
IS there a better controller or stick with OEM ?

Hate to be a pest but figure this is what the forum is for :wink:

I'd have posted a pic of the controller panel but haven't been a member for 7 days yet.:-P

Re: Bad Controller or micro-switch ?
 

Scotty:
Saw your reply after I posted about the controller.
Polarity is all good.
Had also done as you suggested and with charger on and running was showing 47.8V.
Just for grins, with wheels up, I pressed the GO and wheels would spin for a sec, then charger kicks off and wheels stop.
The chargers Amp meter is on zero while charging, like it's not taking any charge ( draw?).

Re: Bad Controller or micro-switch ?
 

Correction: Voltage with charger on was 43.8V
Will check again in a few hours.
Also batteries are all Exide GC115G . All bought new in last 4 months.

Re: Bad Controller or micro-switch ?
 

After charging 8 hours had same voltage- 43.8 ( charger was still "charging" and still on zero on Amp meter."
Assuming the charger is good, it seems like there must be an "OPEN" in the system ? ( IE-the charger not shutting off).

Could a bad controller cause this ? ( based on the finding of the compromised housing)

I hate to spend a chunk of change replacing something that isn't bad. If I DO replace the controller, should I also change out the solenoid as well ?

I use the cart basically on flat ground, around the property, pulling a yard cart for tree limbs, yard debris , firewood, etc.

Re: Bad Controller or micro-switch ?
 

Sounds like 2 separate problems, the controller problem and the charging problem.
1. Do not run any controller that is taped together. Unless the cart is stock and used for golf, the stock golf controller will not suit the need for increased amperage delivery. Even if it is used for golf check aftermarket upgraded controller prices before buying OEM. You can get more amps which equal more power.
2. a charging problem, step one take your charger to another cart (or shop) and test it on another cart.