EZGO 36 Volt No Power Up Hills

[returntoport]

I have a 1999 EZGO 36 volt Series model 1000 utility cart. Everything is stock, wheels/tires no lift. Got it out this year and it will not go up any incline but runs fine on the flat. New batteries last year. Took the motor in and had it gone through new armature, brushes and bearing to eliminate that. Still has same issue. Voltage seems to be fine at the batteries 37.4-37.6. I followed a trouble shooting guide from a previous post and voltage at controller seems to be fine.

[JohnnieB]

Your batteries are only about 80% charged. Full charge is 38.2V. (SoC chart attached)

Were the batteries placed on charge at least once every month over the winter?

What does the battery voltage drop to when trying to go up hill?

Also check the voltage drop of each individual battery. Some may be dropping more than others.

[returntoport]

I did not charge the batteries once a month during winter I charged them full in December and then again in March. I just put the charger on after my last post and checked voltage this morning and it was 37.8. Why would I not be getting a full charge? I unplugged the charger and plugged it back in and it charged for approx. 5-7 mins. Checked voltage with charger on read 44.3. I will check voltage on incline. Thanks

[returntoport]

Checked voltage on incline full throttle half way up the incline about 5 yards it drops to 34.7 and comes to a complete stop and then the voltage climbs to 36.8 but the cart wont move. When I back down the hill I checked the voltage 38.2-38.9 it varies back and forth.

[JohnnieB]

Originally Posted by returntoport

I did not charge the batteries once a month during winter I charged them full in December and then again in March. I just put the charger on after my last post and checked voltage this morning and it was 37.8. Why would I not be getting a full charge? I unplugged the charger and plugged it back in and it charged for approx. 5-7 mins. Checked voltage with charger on read 44.3. I will check voltage on incline. Thanks

Lead-Acid Deep-Cycle batteries self-discharge at about 1% per day and the plates sulfate (aka aging) whenever the charge is less than 100%. The aging occurs more rapidly and more permanent when the charge drops below about 70% SoC, which is typically reached in roughly 30 days of storage after being fully charged.

Sounds like you have a battery charger that shuts of when the On-Charge voltage climbs into the 44V-46V range (typical shutoff point for legacy type chargers). When a lead-acid battery is charged, a "Surface Charge" develops, but it contains little energy and rapidly depletes via self-discharge. It takes about 12 hours to deplete enough for the battery voltage to reliably be used to estimate the battery's State of Charge.

Originally Posted by returntoport

Checked voltage on incline full throttle half way up the incline about 5 yards it drops to 34.7 and comes to a complete stop and then the voltage climbs to 36.8 but the cart wont move. When I back down the hill I checked the voltage 38.2-38.9 it varies back and forth.

It depends on how steep the hill is, but the cart ought to still be moving at 34.7V on a 25% grade or less.

Check the individual battery voltages.

At-Rest, they should all be within 0.1V of each other.

Check individual battery voltages climbing a mild hill. They should all drop to the same voltage on the same hill.