2008 Precedent - Installing 48V -> 12V Transformer/Reducer

[boy09]

I'm wanting to install a 12V cigarette lighter style plug in my 08 Precedent. I ordered a cheap-o step-down transformer from Amazon.

Is there an easy way to go about powering the transformer so that it turns on/off with the key switch? Or what is the best way to go about wiring this?

[yawood]

Originally Posted by boy09

I'm wanting to install a 12V cigarette lighter style plug in my 08 Precedent. I ordered a cheap-o step-down transformer from Amazon.

Is there an easy way to go about powering the transformer so that it turns on/off with the key switch? Or what is the best way to go about wiring this?

The el-cheapo reducer you bought will be a four-wire reducer. If you wired it directly through the key switch you risk burning out the key switch because it is not designed to have the power through it that you need to run the reducer. So your best option is to add a 48V relay. The key will then use a small amount of power to operate the relay and the relay will pass the full amount of power used to turn the reducer on and off. If you had bought a five-wire reducer it has this functionality built-in so you would not need the extra relay and wiring for it.

If you want to go ahead with the relay option there are many threads that describe the installation in great detail, just do a search for them. Here is a couple of pictures and a diagram that show what you need. The first picture gives you the number of the relay required and this is readily available from Mouser Electronics or many other sources. The second picture shows where things are connected at the batteries. The positive connection to the first battery should be through a fuse wired close to the battery. The negative is connected to the black wire with the yellow bullet you will find on the Precedent. This connects straight to the B- connection on the controller and means that the OBC will recognise how much power has been taken by the reducer and put that back when you have the charger on.

[movin-on]

I know hindsight is 20 20, but you just should have ordered a reducer with a trigger wire that connects to the key switch...Not that much more money and saves a lot of time and are normally better quality......

https://www.ebay.com/itm/Golf-Cart-V....c100008.m2219

[boy09]

I can return the one i have, the 5-wire definitely looks like the way to go. Thanks guys.

[yawood]

Originally Posted by boy09

I can return the one i have, the 5-wire definitely looks like the way to go. Thanks guys.

That's definitely the way to go. Just remember that the connections are the same other than connecting the Trigger wire to the "cold" side of the key switch. The photo of the battery area in my post above is the same.