Club Car DS Power Drive charger problem (won't charge)

[Josh Waddell]

(please read entire article before beating the OBC) We have a 98'ish club car DS where I work. Last week the battery light started flashing and it quickly began losing power. We were able to push it into the shop but until yesterday I did not have time to address the problem.

I started reading threads and was able to get the light to stop flashing by disconnecting the battery bank for about 15 minutes. The charger would not kick in while the light was flashing nor would it kick in after I got the light to stop flashing (when the light stopped flashing the battery indicator showed a full charge).

I topped off the battery water, took off and cleaned the battery connections, checked individual voltage 7.4v across the board (connected in a series around 46v). I tried bypassing the OBC by breaking the connection at the yellow fuse holder (receptacle side) keeping the fuse in position and jumping from the fuse to the negative side of the number six battery as posted in other threads. The charger did not kick in.

I then bypassed the relay inside the charger with a nifty jumper made out of two male spade connecters. Viola it works. I know it is now a manual charger. My long story short question that I believe I already know the answer to but would like to verify with the experts here is this. Is it the relay? That might sound silly, I just want to verify the testing methods were correct before I buy a relay that isn't bad. Any other tests needed to verify it is not the OBC or the funky little circuit board in the charger?

I don't want to toot my own horn but I know my way around mechanics. There are two things I don't do well with, circuit boards and little magic black boxes that wires go into and come out of but ya don't know what's inside cause it's all glued up like now one wants you to look at!!!!

[Josh Waddell]

This is an onboard charger, no receptacle.

[teecro]

Was there voltage on the coil of the relay before you removed it? The OBC sends battery voltage to the coil of the relay closing it and thus allowing the charger to turn on and charge the batteries.

[jjance]

My guess would be bad batteries. You have to low a voltage for the charger to turn on. After you charged them manually was everything back to normal or was the voltage still low?

[teecro]

Originally Posted by jjance

My guess would be bad batteries. You have to low a voltage for the charger to turn on. After you charged them manually was everything back to normal or was the voltage still low?

I missed his math... 7.4 x 6 = 44.4 volts not the 46 as stated.... Voltage was indeed too low for the charger to kick in normally. What is the voltage now and if you return the relay connections to as they were does the charger still not work?

[Sergio]

I think your diagnostic is correct (bad charger Relay), it also explains why the warning light did not quit blinking when you plugged the charger in as the OBC did not "sense" the relay coil.

The Minimum operating voltage to close the relay coil (according to the manual) is 34v.

The datasheet for the relay specifies a maximum of 36v is needed to trigger the 48v coil, so either way You have plenty voltage.

Make sure You charge those batteries as soon as You can as it is not good for them to stay at that low SOC for any period of time.

If You do it manually with the by-pass, just unplug the charger when the pack gets up to 60v.

[jjance]

On second thought you most likely have a bad OBC. Just closing the relay shouldn't start the charger. You also need to turn on the SCR in the OBC to complete the circuit.

[TahoeDawgZ71]

It sounds like a relay failure to me. If the relay doesn't fix it, it could be a problem with the AC Interrupt circuit board.

[Josh Waddell]

First, sorry for bugging out last night. We are in the middle of moving.

Second, Sergio I was to tired to babysit the charger by the time I had jumped the relay. (I wrote the article on my way to bed =-)

Third, jjance as stated to Sergio I was unable to watch the charger and did not want to leave it plugged in unattended.

TahoeDawgZ71, is the AC interrupt board the circuit board in the charger?

TO ALL, Thank you for your support and advice. I am going to charge the pack up with the override in place and will check in with you later.

[TahoeDawgZ71]

Yes it's the board in the charger. On an external charger, the relay is switched when the OBC provides power to it via the DC cord. On an Onboard charger, the DC cord is hardwired to the battery pack, therefore it's always "plugged in" Thr AC interrupt circuit board breaks that circuit unless the AC cord is plugged in. This keeps the solenoid lockout feature of the OBC from staying on all the time and keeping the car from running. The AC board does the switching of the relay when the AC cord is plugged in. If it fails, the relay will not click. I recommend removing the relay, applying 48 volts to the two small coil posts and seeing if it clicks. Let me know what you find.