DCX came on and now it won't.

[Coltf1991]

Originally Posted by scottyb

IF 6 batteries are dropping to 20v under load, how can they all be good? Maybe they are cabled up incorrectly? or the cables are bad? or loose?

My cables are brand spanking new. I dont have them cabled up wrong.. They are not loose

[JohnnieB]

Originally Posted by Coltf1991

My cables are brand spanking new. I dont have them cabled up wrong.. They are not loose

Colt,

In addition to Ohm's law; Murphy's Law, Finagle's law and Sod's Law also apply to Golf Carts.

If I understand the situation correctly, B+ to B- measures 37.6V at rest and when you press the accelerator, B+ to B- drops to 20V.
That tells me there is something amiss between B+ and B-, nothing more, nothing less.

If faced with this situation, I would press the Neg probe of my DVM hard enough to dimple into the most Negative Lead battery post (B-) of the pack, the Positive probe into the Positive Lead battery post of the same battery and write down the at rest reading and the under load reading. Then I would leave the Negative probe as is and move the Positive probe to Positive Lead battery post of the next battery in the series chain and note the same two readings. Leaving the Negative probe connected to the most negative lead battery post, I would measure the incrementally higher voltage across the four remaining batteries in the series chain.

If stepped voltage does not increment in even steps, both at rest and under load (roughly 6.2V each), something is wrong.

If the voltage does step evenly, measure across the cables from the battery pack to the controller. If any voltage above a millivolt or two is measured, there is a problem in that cable or its connections.
(Note: This technique can also be used on the interconnecting cables in the battery pack)

Of the things I learned in my 50+ years of repairing electrical and electronic devices, the ones that stand out the most are:
New parts fail, sometimes they are DOA, other times they only work for a short time.
Suspect work done by others, and suspect work done by self even more.


PS - Nice cables

[rabbitreborn]

ok I use alligator clips on my test leads (makes my life easier).

1. Clip to B+ and B- on controller, Pedal Down, record voltage (less than 37 go to next step)
2. Move clip from B+ on Controller to Controller side of Solenoid, Pedal Down, record voltage (less than 37, proceed to next step. If 37, then bad cable between Solenoid and Controller is bad)
3. Move clip from Controller side of Solenoid to battery side of solenoid, pedal down, record voltage (less than 37 proceed to next step. If 37, then solenoid is bad and needs to be replaced)
4. Move clip from battery side of solenoid to positive on front battery passenger side, pedal down, record voltage (if less than 37 proceed to next step. If 37 then cable between battery pack and solenoid is bad)
5. test each individual battery with pedal down.

It's a pretty simple process... somewhere along the line you are losing basically half the pack voltage, you just have to test everything to figure out where the voltage drop is coming from......

[Coltf1991]

Alright boys. Thanks for the help so far. I am super slammed at work today, won't get any cart time. Hopefully I will soon and get this figured out. I am going to try both of your guys procedures see what I come up with. I will post my readings exactly when I get time.

Thanks,

Colton

[Coltf1991]

Well I started at the main pack negative and as I went around to each batteries positive terminal it went up over 6 volts each time. Didn't do it with a load yet but did go until it added up to 37 v

[Coltf1991]

Well we have determined that the solenoid is bad. That is where my voltage drop is coming from. How can I bypass the solenoid temporarily?

[Coltf1991]

Okay well I did a bypass just for a second. Put it in fwd and pressed the gas pedal. The wheels spun in reverse, my f1 and f2 are not backwards. I turned the key off and the wheels still spun. The only way I could make them stop is by flipping the run/tow switch to Tow. What is that all about?

[Coltf1991]

Here are my readings going through the series chain starting with battery 1:

B1: rest-6.21v load-6.20v
B2: rest-12.40v load-12.38v
B3: rest-18.58v load-18.55v
B4: rest-24.73v load-24.70v
B5: rest-30.89v load-30.84v
B6: rest-37.30v load-37.02v

Like stated above the solenoid is no getting power across to the other side. Therefore the resistor is getting so hot, you can't touch it with scaring yourself I guess it is acting like a jumper since the solenoid is not working.

[Coltf1991]

Here are my readings going through the series chain starting with battery 1:

B1: rest-6.21v load-6.20v
B2: rest-12.40v load-12.38v
B3: rest-18.58v load-18.55v
B4: rest-24.73v load-24.70v
B5: rest-30.89v load-30.84v
B6: rest-37.30v load-37.02v

Like stated above the solenoid is no getting power across to the other side. Therefore the resistor is getting so hot, you can't touch it with scaring yourself I guess it is acting like a jumper since the solenoid is not working.

[Coltf1991]

Nobody????