charging issue 03 ds iq

[_ogre]

i have an 03 ds iq charging issue. cart runs well, 2 yr old batteries, cart is used daily, typically not for long, sometimes only a couple hundred yards. i typically charge my cart at 49 volts, i believe last time i charged it, the cycle did not finish, i am down to 48.1 volts with very little use. nothing has changed, no work has been done on the cart.

currently when plugged in the powerdrive 2 charger does nothing. no click, no nothing. i went thru the "charging system trouble shooting" thread in the stickies. pack voltage is 48.1 on the digital dash gauge, confirmed with multimeter. yellow fuse on grey wire checks good, as does the fuse on the black wire on back of charge receptacle. in checking the charger relay.... i'm only getting 36 volts at the 2 small posts at relay, this should be pack voltage, 48.1volts. checking further, 36 volts at the plug wires inside the charger. on the cart, between the red receptacle wire and the black receptacle wire at the fuse is also 36 volts. again, my pack voltage is 48.1. i bypassed the relay for an hour (50.2 volts) before heading to the house with the cart. i'll set up a smart plug to get a 6 hour charge tomorrow.
ideas?

[sthreatt]

The 36 volts you're reading at the receptacle pins is coming from the on board computer and "should" be enough to activate the relay in the charger. Sounds like a bad charger relay.

[TahoeDawgZ71]

It's normal to read below pack voltage at the charger receptacle, and also at the two wires which energize the relay UNTIL the OBC commands the charger to turn-on. Once the turn-on command is provided by the OBC, the voltage will rise to full pack voltage as the OBC closes that circuit and allows full access to the battery pack. Here's what you need to try next. Plug the charger into the wall, plug the charger into the cart, pull apart the yellow rubber fuse holder on the grey wire that runs into the back of the OBC. Leave the fuse in the side of the connection that runs back into the charger receptacle and let the other end that runs back to the OBC hang freely and disconnected. Take a jumper wire with alligator clips on it and clip one end to the metal exposed portion of the fuse in the fuse holder and place the other end of the jumper wire on the MAIN negative battery terminal. This will be the Rear-most battery on the driver's side of the car that has the negative cable attached to it that runs through the hole in the OBC. Once this connection is made, do you hear the charger relay click? If so, you have a bad OBC. You have now proven that the charger relay can be energized from the vehicle when provided a direct connection to the main negative terminal, a function that the OBC SHOULD BE providing, but can't. If this happens, replace the OBC and you'll be good to go. If it still doesn't click, you're going to find that you've got a problem with your charger relay, voltage suppression diode within the charger wiring, charger cord, or a bad solder joint at the grey wire where it's soldered to the pin inside the charge port.

[_ogre]

Thanks guys, I went through all the troubleshooting that tahoedawg suggested. I also checked continuity of the charge plug and charger cord. I unplugged everything and checked continuity on every wire. Then while I had the relay bypassed and the charger on, I was jumping the relay and heard it clicking. It's working, I have no idea what I did. Obviously a loose wire or connection, I'm sure it will rear it's ugly head again. So thanks again

I do have a question. On the low voltage side of the relay, there are two wires to energize the relay, but there is a red jumper between the two. Whaa???

[movin-on]

The red wire between the terminals is the voltage suppressor...It contains a diode..

[TahoeDawgZ71]

As mentioned above, the wire that jumps them together contains the voltage suppression diode. The diode absorbs the "shock" of the relay turn-on signal from the golf car and prolongs the life of the relay coil. Without it, it would still work, but the relay wouldn't have as long of a life span.

[_ogre]

So. I have a gremlin and it's back already. At least I believe it is a broken wire somewhere. To this ogre a relay works or it doesn't, not so sure about the OBC. I'll start checking continuity a little more carefully

I should have known it was a diode, they're typically built in automotive relays. brain fart, thanks

[movin-on]

You can test the suppressor...

1. Disconnect AC cord from the wall outlet and DC plug from the vehicle receptacle.

2. Using a multimeter set to the diode test function place the black (–) probe of the multimeter on the sense lead pin (short pin) of the DC plug. Place the red (+) probe on the positive (+) pin of the DC plug.
The multimeter should indicate no tone. If a tone is emitted (indicating a closed circuit) then the voltage
suppressor has failed and should be replaced

[Fairtax4me]

When measuring voltage between wires at the cart receptacle, you are measuring the drop across the circuits in the OBC which have resistance, and will not give you an accurate measurement, or at least in this case, not the measurement we're looking for.
Measuring across the pins in the receptacle can tell us some information about the condition of the OBC, but we don't need to get into that yet. When measuring voltage at the relay in the charger, keep you black meter probe on the Pack Main Negative, and that measurement should be very close to pack voltage.

Almost always when I've had intermittent operation of a charger it has been a problem at the cart receptacle, or charger DC plug. Loose or corroded wiring on the back of the receptacle is common. Loose or damaged pins in the DC plug are also somewhat common, but this is usually because of a bad connection with the receptacle, or dirt in the receptacle making it excessively difficult to insert and remove the DC plug.

Check the wires on the back of the receptacle for corrosion or fraying. Give the grey wire a tug and see if it just pulls out of the receptacle. If it does, the receptacle should be replaced.
If wiring looks OK, use contact cleaner and compressed air to blast out the pins to clean them. Sometimes that makes all the difference.
If the DC plug is hard to push into the receptacle use a silicone spray or light silicone grease on the pins and insert/remove the plug several times to help clean off the contacts, then clean everything again with contact cleaner and compressed air.
A quick shot of silicone spray in the receptacle will help keep the pins lubricated and the plug will be much easier to insert, and will also make better contact of the pins. If you've ever noticed the DC plug seems hot, poor contact between the plug and the receptacle pins is often to blame, and lubricating the pins with silicone will quite often help with this.


As for checking the charger for operation.
With the AC cord Unplugged, Plug the DC cord into the cart. Wait 10-15 seconds, and listen for the relay to Click. Does it click? If no, Use a voltmeter to check for pack voltage on the Grey wire pin by probing the back of the charge receptacle. Black meter lead should be clipped to pack negative. Remove the DC plug for 10-15 seconds and plug it back in while probing the grey wire pin.
When the DC plug is first plugged in this should show very close to full pack voltage. If it is significantly Less than pack voltage, about 35v or under, then there is a wire problem or connection issue that needs to be checked.

If it is near pack voltage, Keep your red meter lead on the grey wire pin and wait for the OBC to command the relay On.
When the OBC commands the relay On, it pulls the grey wire to negative, the relay should Click, and you should see the voltage on the grey wire pin drop to 0v or very close to it.

There is a time-out for the relay operation if the OBC does not detect charging, so you may need to unplug the DC cord for several seconds and plug it back in while monitoring the voltage on the grey wire pin. If the OBC does not command the grey pin to negative (voltage does not drop to 0v), then you most likely have a problem with the OBC.
If the OBC is bringing the grey wire to 0v, it is giving the command for the relay to Click On. If the relay does not click on the relay is bad. Double check that there is pack voltage present at the relay to rule out a connection issue.

[_ogre]

Thanks fairtax, I was checking continuity on the grey wire and it's iffy. I just now tugged it off the back of the receptacle. I'll PM David