2008 Precedent Replaced Speed Sensor - Problem persists

[tonydutt]

Hello All,

I have read most online postings about my 2008 Club Car Precedent 48V speed problem and can't find a solution.

Problem is cart will only go about half speed on a full charge. Here is what I have done:

1. Replaced the Speed sensor (ADC motor)
2. Tried the speed sensor test - pushed the cart forward and received no beeps from the reverse sensor.
3. Verified batteries are topped off with distilled water.

Here are some questions:
1. The speed sensor I took out had a magnet that was a segmented circle. Basically it had two salient ends 180 degrees apart that arced about 30 degrees or so each. The one I replaced it with was a complete circle. Is this causing the unit to not count the RPMs and see no delta as the magnet rotates?
2. Is there another part of the speed sensing circuitry I should look at? I have seen some posts about spraying WD-40 of the "gas" pedal. Is there a potentiometer that I should inspect there?
3. Is it normal for the unit to drip a white corrosive substance? Thinking of switching to gas because of this.

Thanks many.

[mrgolf]

As usual to start with a problem like this we need to know the pack voltage 12 hours after a full charge. Also voltage of each battery under load. What part is leaking. Maybe a photo of battery pack and area that leaks.

[tonydutt]

I have measured the battery voltages a various times after a charge and I get about 8 volts each and a pack voltage of about 48 volts.

As far as what is leaking - hard for me to see. Nothing is leaking out of the top. All terminals are clean - no sulfates building up on any terminal although that is what this substance looks like. No battery levels seem to be getting lower with any periodicity.

I attached two pictures. One of the top of the batteries and one of the undercarriage -where you can see the sulfates. Without taking the batteries out I can't really diagnose the problem. Just looking for previous experiences. I really want to get the speed fixed and sell it.

Thank you.

[basshawk84]

Fully charged should be 50.8 volts or greater. If you're only getting 48 volts after a charge, your problem is the battery pack.

[tonydutt]

Sometimes, it will take off on full speed for about 5 seconds or so and then slow down. This performance seems to indicate a problem other than the battery and this was an instantaneous issue, it didn't occur over a period of time. I will measure the batteries again, but, in the case where the battery is not the issue, what else could it be?

[mrgolf]

You still have a problem with the speed sensor. It could be bad, I know you have changed it but sometimes you can get bad new parts. Either that or the wire connections are corroded. Try putting the old magnet back in with the new sensor. That corrosion needs to be cleaned off before it causes more damage. Backing soda, make a paste with a little water and brush it on. Let it set a while then clean it off. Also you can use a brass wire brush wheel on a drill or angle grinder to help.

[smokey tennis shoe]

Batteries. Also that white crap on the bottom is from the batteries.