1996 48v Club Car Voltage on Frame

[Kolassus]

Hello all. I need some help/advice. On routine maintenance of my cart, I found that I have voltage on my frame. The numbers I am going to give will be readings from the time I post this message. The battery pack is reading 51.4v. If I put my black probe in the Negative Post of the pack (battery 6 in the series) and the red probe on any portions of the frame I get a reading of 45.4v. If I put the red probe on the Positive Post of the the same battery as above and the black probe on any part of the frame I get a reading of 37.1v. I get the same readings if the key switch is on or off.

The cart is running great. No issues aside from the solenoid sticks every now and then. I have modified the cart heavily with a lift kit, wheels, an Alltrax 500 controller, a A1 motor, HD F&R switch, all new 2g wiring, and 400 amp Solenoid from ScottieB. I cannot find anything grounded to the frame or any exposed wires. The only place I think it could be would be where the solenoid is mounted. Any thoughts? Will this hurt my cart in the long run? I dint want to blow out my motor or controller. Any advice would be awesome. Thank you.

[R&TBabich]

Originally Posted by Kolassus

.... I cannot find anything grounded to the frame or any exposed wires. The only place I think it could be would be where the solenoid is mounted. ....

To rule out the solenoid pull the leads off and measure for continuity to the frame from the posts.

[mrgolf]

You likely have very very low amps. The voltage can leak through cables batteries or components. If you put a light in line with that voltage it will likely not light the light. I got voltage from me tires one time.

[Kolassus]

I do not read any amps in any wire when the cart is not in motion and the switch is off. But could low amperage voltage hurt anything? Will it draw down my batteries?

[Cartmaster]

try making a strong solution of baking soda/sodium bicarbonate. Whatever you call it over there! spray over the batteries and all around the battery tray. before doing this, put your neg meter probe on the neg terminal of a battery and probe around the battery plastic top with the pos probe. I am pretty sure you will read volts. then wash down with the bicarb and rinse with clean water and dry off as best you can. now do the test again on each battery with your probe. you should find a much lower or no voltage showing. If you find this works, maybe remove all the batteries and go over everything around the batteries and the battery tray with the bicarb. If successful, you just need to check it occasionally and wash down again if voltage shows. This stray voltage can shorten battery life and reduce your travel time. to help prevent it happening again, regularly wash and dry your batteries as part of your battery maintenance schedule

[Kolassus]

Ok, so I disconnected the main post I’ve lead from the battery. I do not see any continuity from the lead to the frame or to the solenoid mount.

What is weird though, is that I am still seeing 44v on the frame when I put my probe on the main battery pack negative and the other probe anywhere on the frame. This is with the positive lead of the battery pack disconnected. Doesn’t make sense to me. If the positive is disconnected, how can there be any voltage on the frame? Isn’t the circuit broken if the positive is disconnected? At 44v, it would have to be the whole pack that is leaking voltage I would assume, but that doesn’t make sense. Please help. Thank you...

[Sergio]

Did You clean the batteries and surrounding areas with a mix of 1 lb (1 cup) baking soda mixed with 1 gallon of water as Cartmaster suggested?.

The electrolyte mix does provide a conductive path for a few micro amps.

Do You have a Lo-Z (low impedance meter) in order to eliminate ghost voltage readings?

If not You can also do as mrgolf suggested and place a small load (light bulb, resistor, etc) in parallel with he same points you are measuring this voltage to see if it disappears.

[Kolassus]

Ok, so I did both of the above. I cleaned all batteries with baking soda and then used an old 12v taillight as a “tester”. With the negative wire on the Pack Battery Post and the positive wire touching any part of the frame, the taillight lights up. What does that mean? Light seemed steady. Same brightness as if I hooked it up one of the 8v batteries. I would think since it’s reading 45v on my multimeter that the light would be super bright, but it isn’t.

One curious thing that happens though. At some point during my cleaning, I actually read 0v on the frame. I thought the cleaning did the trick. However, when I went to drive the cart, it was dead. I could hear the main solenoid switching, but no movement on the cart. But I was reading 0v in frame and full charge on pack.

Just to rule out the OBC, I disconnected the main Negative of the pack, turn the cart on, and pressed the pedal to try and drain all residual power (trying to reset OBC). When I reconnected the negative, I had full power and the cart drove perfectly. However, the voltage is back on the frame. I am reading 44v again from the main Pack negative terminal to anywhere on the frame. What is going on???

[Budule]

i would pull the batteries out too get a good looky look.....my OCD would not allow me to let that slide , even though it may not hurt anything , i would have to find it....

and the fact that you temporarily "fixed" it whilel messing with the battery area tends to steer one in that direction.... if no problems in the battery box then i would start isolating anything bolted to the frame and see if it disappears....

[Sergio]

I definitively agree that if the connection can pass enough current to light an incandescence light bulb of a few watts (not a test light), You need to locate the source.

I was thinking You could disconnect the pack positive battery cable.

Place the voltmeter negative probe on the frame.

Start with the disconnected pack positive battery post and measure the voltage from that post and then every post in series until you get to pack negative battery post.

If the issue is coming from one of the batteries, the voltage will read zero volts when you touch the battery post.