36 volt to 12 volt converter question.

[Retired70]

I installed a 36 volt to 12 volt converter in a 2001 EZGO TXT. The pack voltage in is 38.9 volts. Voltage at the output side is 12.5 volts. I took this reading at both sides of the wire harness connector. I ran the 12.5 volt power and ground to the main positive and negative polls on an automotive style fuse box. Now here’s the question, I took a reading at the positive and negative inputs on the fuse block and found that there is only 0.21 volts present. These are the same wires I read 12.5 volts at the wire harness connector. It’s a simple install, so what am I doing wrong?

[Retired70]

I thought I should add that this is a series cart. The voltages were checked with the key switch on and the cart in gear. I did a continuity check on all connections and especially those on the fuse / distribution block. All connections test good. (Continuity)

Now one thing I noticed, when checking converter output at the positive input poll on the fuse / distribution block I would check from the positive input to the battery pack ground. The reading was also 0.21 volts. Now if I took a reading from any other negative post in the pack I get 12.5 volts. If I moved the ground from the distribution block to any other negative post in the battery pack the 0.21 volt reading would follow. Per the converter installation instructions, all negative ground connections are to be made to the negative post on the battery pack where the black wire from the converter is connected. In order to facilitate this using a distribution block I ran a wire from the main negative post on the distribution block to the battery pack negative post, the same post the black wire from the converter is connected. I don’t understand why this is not working.

[Capt. Lenny]

I would start by re-checking all your connections including crimp connections. I almost sounds like you have a bad connection at the output pigtail of your white connector. I see that's the last place that you are getting 12.55 volts in your picture. Try taking a voltage reading at the fuse block while wiggling the white connector. Here's a 3rd hand trick, attach alligator clips to your test probes. Just fasten the probes under the screw.

[bronsonj]

Also I see you using the term 'ground'. That's what we always did with cars, but the negative lead should not be connected to the frame of a golf cart. Ever.

You need to run a positive and negative lead from the converter to the distribution block. If you have a distribution block with both positive and negative sides, great. If not you can create your own negative distribution block or for a cleaner look replace it with one that has both positive and negative connections, like marine applications. When you wire accessories you'll need to have both a positive and negative wires run to them.


If you didn't use the frame as the 'ground' and just ran positive and negative leads then it sounds like you have a broken wire or bad connection.


--- edit ---

I just noticed, this is an all Florida post so far... SW Florida, Palm Harbor and St. Pete. Kinda cool to be talking with my neighbors about a cart

[adrianp89]

Sounds like you are metering in correctly on the block, or on the block + and - are reversed.

You have the power - something is incorrect at the fuse block.

[Retired70]

Thanks for all the replies guys. I didn’t have much time to work on the cart today but I did listen to the advise. The first thing I did was disconnect the positive and negative inputs to the fuse block. I was curious to see what kind of voltage was present. I took a reading of the output side of the converter at the positive output and the negative wire connected to the pack negative post. This wire was connected to the negative post on the fuse block. I got a reading of 13+ volts. But I wiggled the red wire at the harness connector and the voltage fluctuated from 13+ volts to zero and back. That’s where I had to leave it due to another commitment. But I believe that the red (positive output) does not have a good connection and may need reseated. I’m hoping I can spend some more time with it tomorrow. I want to take the wire harness connector apart and get a better look at it. After that I can take a look at the fuse block.

[Cobra,1]

Agreed bad connection.
Ground on a golf cart is negative battery connection.
Nothing ever gets grounded to “ frame ground” as some converter may recommend such as used on automotive application.

[Retired70]

It’s been a while since I’ve commented on this post. Since then I contacted the seller I bought the power converter from to see if he could sell me another wire harness pigtail. Well he sent me another complete unit, at no cost! That was unexpected. So just as soon as I get a chance I’ll swap them out and report on the results.

[Retired70]

Here’s the resolution to the problem. As it turned out there was a wiring problem where the connector was not making good contact. The vendor that I bought the power converter from sent me a complete new unit. Problem solved! The vendor sells on ebay as Augusta Golf Carts LLC, and he is the area distributor for those parts and many more. Shop his site, maybe he can help you out and save you some money too.

[Cobra,1]

Nice to hear a good outcome.👍
My similar problem with factory wired fuse block and convertor was old out dated glass fuse’s
Fuse block. Upgrade to a mini fuse fuse block solved the problem.
Glad you got it solved.😊