Lighting Trouble

[LizardLeg]

My cart - 2008 EZGO TXT, series - came with headlights installed. Typical car style pull out switch on the dash that is operational all of the time, not just when key is on. This is fine as sometimes I need the lights but want the cart off for safety reasons.

I installed rear LED lights last night. They look good and work great - however. With the headlight switch off, when you hit the accelerator to take off, the taillights come on dimly. If you floor it for a few seconds, they go off - until you let off the accelerator pedal.

I haven't had a chance to dig into the wiring of the switch - it was late by the time I finished - figured I'd ask here to see if it was a common problem before tearing it apart.

Thanks!

[gornoman]

LizaedLeg, Welcome to BGW!

I have experienced this condition myself on occasion but only after washing the cart. Seems there is some stray voltage floating around the chassis when it's wet, and the LED's seem to pick up on it. Pay particular attention to the ground wires on your headlight/taillight circuits. All grounds must go to the negative 12v reference point. No frame grounds allowed on sparky carts. Also, make sure that headlight switch is NOT grounded to any metal on the cart.

[LizardLeg]

Thanks! I'll check the switch when I get home tonight. Cart was dry when the work was done.

This is the first electrical work I have done on the cart, but the +/- for the lighting comes straight off of 2 of the batteries for 12v. All wires to the new tailights are soldered and heavy duty shrink tubing over that - it is a hunting buggie so I wanted it to be durable. Tailights are cut in recessed into the body LED's and the front are cut in recessed 55w Halogens. About the only thing that can be touching metal is the switch, and even that is doubtful.

[LizardLeg]

Checked the switch and all wiring on the lights - front and rear. All fine. Disconnected the lights from the battery entirely - still have voltage on the frame. The highest voltage I read (probably from better contact) is one of the controller motor cover bolts - 15.43v (??)

New to carts, but familiar with electronics - any thoughts here??

[Russ/TN]

Are your batteries spotlessly clean and dry?
A few months ago, I had a similar situation.
Even with the battery pack completely disconnected, I would get 20+
volts to the frame.
The current was traveling through the residue of boiled-out electrolyte on the batteries.
Try this...
+ lead of meter connected to Battery pack +.
Take the - lead of the meter and drag it around on the tops of the batteries.
I was able to get almost full pack voltage through the gunk on top of the batts.
Stray voltage to the frame dropped to 0.2 volts after I removed and thoroughly cleaned and dried my Batts.

I have a friend who has 3 red LED marker lights mounted in the bag well directly behind the motor.
He gets the same "ghost light" effect from his only when the accelerator is pressed even when they are turned off.
I think it is inductance from the electromagnetic field of the motor.
Good luck.

[gornoman]

Originally Posted by Russ/TN

I have a friend who has 3 red LED marker lights mounted in the bag well directly behind the motor.
He gets the same "ghost light" effect from his only when the accelerator is pressed even when they are turned off.
I think it is inductance from the electromagnetic field of the motor.

I like that theory a lot. I can't confirm it, but I like it.

[LizardLeg]

Batteries are brand new and spotless - I'm leaving Saturday after Christmas dinner to head to the woods for a week of hunting - with the voltage on the frame, I'm not going to get left stranded because it fried the controller etc am I?

[gornoman]

Here's a good test. Rig up a regular tail light bulb or side marker bulb (12v bulb) with wires. Attach one wire to the MAIN PACK POSITIVE and the other wire to the frame. If the bulb lights you have an issue somewhere. If the bulb stays dark you have harmless surface charge on the frame somehow and you should be fine. If there is no CURRENT there is no draw on the pack.

[LizardLeg]

When i was testing the other day, it seems as if the + voltage is on the frame. Hooked up my Fluke to the - battery terminal, stuck the postive probe on one of the bolts for the controller cover, or the frame, etc and was reading 15.4v on the controller bolt and 3-5v on the frame, depending on how clean, how much paint, etc was there.

I'll try the light trick this evening.