Jump to content

Welcome to TheMalibuCrew!

As a guest, you are welcome to poke around and view the majority of the content that we have to offer, but in order to post, search, contact members, and get full use out of the website you will need to Register for an Account. It's free and it's easy, so don't hesitate to join the TheMalibuCrew Family today!

Lifeform LF9 Wiring


TexasTurner

Recommended Posts

Just installed my Lifeform LF9 lights on the boat (2018 21 MLX). I have a question about wiring. Obviously the boat is pre-wired for the swim lights. I checked the voltage out from the factory wires and it reads 12 VDC. According to the Lifeform website the lights should not be wired directly to the PDM module or "the lights will not work correctly", whatever that means. I assume this means don't plug the lights directly into the existing wires. The website has a very complicated diagram adding a relay into the mix.

 LF9_Titan_Wiring_Example.pdf

One of the marine stereo installers around here told me I needed this 5 prong relay, so I bought two of them. I plugged the (+) wire form the boat into 30 on the relay, (-) wire from the boat into 85, (+) wire from the light to 87A and (-) wire from the light to 86 and nothing into 87. The reason I did 87A vs 87 is because I was not getting any voltage from 87 where as I was getting 12 VDC from 87A when the lights were turned on from the screen.

After doing this I turned on the lights and they both came on and were bright for about 1 second before they dimmed. I am assuming this is the overtemp protection built into the light.

My questions are. Do I even need the relay since I am already getting 12 VDC from the pre-installed wires? If I do need a relay, do I need a 5 prong or 4 prong? If I need the 5 prong relay, do I have it wired correctly? I feel like using this relay requires another positive power source from the battery but I really don't know.

I hope this is clear as mud. 

Link to comment

I would recommend that you run an appropriately sized and fused power wire (for the amperage draw of the lights) from the 12v + battery power post on the port stringer in the engine compartment to the 30 on the relay, wire the boat's underwater light harness switched 12v + (I think it is a blue wire on the harness plug) to the 86 on the relay, wire the other harness plug wire (black) to the 85 on the relay, then wire your light's 12v + to the 87 on the relay, then use an appropriately sized wire from the light's 12v - to ground (like the engine block ground post). 

There should be a recommended wire and fuse size for the supplied power and ground from the light manufacturer.  You can also check online for the correct wire size and fuse needed for the amperage draw and length of wire you are using.

https://www.google.com/search?q=wire+amperage+chart&oq=wire+amperage&aqs=chrome.2.69i57j0l15.4989j0j4&sourceid=silk&ie=UTF-8#imgdii=jkQpCQMB_JdZ2M:&imgrc=jkQpCQMB_JdZ2M:

 

  • Like 1
Link to comment

I just did this install recently as well. They recommend the relay because there were instances of people wiring directly to the PDM and when they shut the lights off on the touch screen the lights didn’t go out. Only disconnecting the batteries would shut them off. It took me a minute to figure out the wiring and watched a couple YouTube videos on relays that helped me make sense of it all. When looking at the wiring diagram from Lifeform the red box is the relay. As you can see there are 4 lines coming out of that box so all you need is a 4 prong relay. Prong 85 goes directly to ground. Prong 86 gets its power from the swim light wire harness if you want to use the touch screen. Prong 30 is direct from the battery (make sure to add an inline 10amp waterproof fuse), and prong 87 is the power wire from the lights. Make sure to ground the remaining wire off the lights and that should do it.

This video really simplifies it. It shows 87 going to an HHO cell but for your application it would be going to the power wires of the light.

https://m.youtube.com/watch?v=46nlei-2e4k

 

  • Like 1
Link to comment

You only need one relay to power both lights, unless you wanted to control each ON/OFF independently. A 4 or 5 terminal "Bosch" style relay is as about as basic of a relay schematic as it gets. 

The reason a relay is suggested in this application, is because the aftermarket light manufacturer does not not want to be responsible for burning out the boats $1200 PDM. That module is designed with the current draw of the Malibu OEM lights, with maybe a slight cushion. Wiring  in a light that draws more then the designed load, could burn it out. Using the relay shifts the current load to the relay and allows the PDM to just trigger the lights on. 

  • Like 3
Link to comment
9 hours ago, csleaver said:

I would recommend that you run an appropriately sized and fused power wire (for the amperage draw of the lights) from the 12v + battery power post on the port stringer in the engine compartment to the 30 on the relay, wire the boat's underwater light harness switched 12v + (I think it is a blue wire on the harness plug) to the 86 on the relay, wire the other harness plug wire (black) to the 85 on the relay, then wire your light's 12v + to the 87 on the relay, then use an appropriately sized wire from the light's 12v - to ground (like the engine block ground post). 

There should be a recommended wire and fuse size for the supplied power and ground from the light manufacturer.  You can also check online for the correct wire size and fuse needed for the amperage draw and length of wire you are using.

https://www.google.com/search?q=wire+amperage+chart&oq=wire+amperage&aqs=chrome.2.69i57j0l15.4989j0j4&sourceid=silk&ie=UTF-8#imgdii=jkQpCQMB_JdZ2M:&imgrc=jkQpCQMB_JdZ2M:

 

I really appreciate the help! I think I understand it now. My follow up question is; is there a buss bar for power and/or ground somewhere toward the back of the boat? Not sure what you mean by stringer but I’m assuming maybe behind the breakers on the port side engine compartment? Thank You!!

Link to comment

In the engine compartment, screwed down to the top of the port stringer, near the removable panel that divides the engine from the port rear storage, you should see a threaded post with some red battery cables connected to it (one of the cables goes to the starter).  That post has a cable that is connected directly to the battery switch.  It is a good place to connect your fused power supply wire to the 30 on the relay.  On the motor, near the power post, you should see some black ground cables (one goes to the batteries) connected to a stud on the engine block.  That is probably the best place to connect the ground wire for the lights.

  • Like 1
Link to comment
2 minutes ago, csleaver said:

In the engine compartment, screwed down to the top of the port stringer, near the removable panel that divides the engine from the port rear storage, you should see a threaded post with some red battery cables connected to it (one of the cables goes to the starter).  That post has a cable that is connected directly to the battery switch.  It is a good place to connect your fused power supply wire to the 30 on the relay.  On the motor, near the power post, you should see some black ground cables (one goes to the batteries) connected to a stud on the engine block.  That is probably the best place to connect the ground wire for the lights.

Thank you! I'll look when I get back home.

Link to comment

I’m getting feed back in the speakers when I turn mine on. Power/ground for relay coming from posts near engine and power/ground for the lights coming from the OEM wire harness. Any ideas why??

Edited by vaporbluebu
Link to comment

Obviously I'm no expert but when I had this problem on my last boat I moved the ground from the motor mount to the negative terminal on the battery and the noise went away. I would say that your ground is the issue (ground loop) or you're running your power wire too close to your speaker wire, most likely the first one. That is why I asked if there was a grounding buss in the rear of the boat, otherwise I'll run my ground from the lights directly to the negative battery terminal.

  • Like 1
Link to comment
8 minutes ago, vaporbluebu said:

I’m getting feed back in the speakers when I turn mine on. Power/ground for relay coming from posts near engine and power/ground for the lights coming from the OEM wire harness. Any ideas why??

And as I understand it now, your relay should be activated by the existing swim light wires, power for the lights (i.e. 30) should come straight from the battery and/or that connection on the port side engine compartment and the ground on your light should go to a good solid ground.

  • Like 1
Link to comment

Electrically, yes. if it was me, id find the pre-wire harness under the helm, connect my relay there. grab fused B+ and GND from the helm BUS supplies and not mess with anything in the engine bay B+ or GND wise. 

 

Stereo noise, id look way the audio is picking up what the lights are laying down, feel me? Likely more to do with the audio, then the lights. 

Link to comment

Use a relay (1 relay per light ) wire the relays up for a positive trigger (google it there are plenty of easy diagrams).battery power for relays use the post port side of the engine when you remove the divider you’ll se the red cap use a ring terminal 

spilt the battery wire after a 15a fuse into 2 wires (1 goes to each relay) make sure they are even lengths . Ground the relays using the factory wire in each connector for underwater lights 

use each positive wire from the factory connector to trigger the relays 

there is a black wire with a male barrel conntector in the harness where the factory swim light connectors are use that for the ground wire to the lights I swing the same 1 into 2 split 

 

it will provide the same amprage to controller thus causing no issues and no ground loop noise 

Link to comment
7 hours ago, Sdva said:

Use a relay (1 relay per light ) wire the relays up for a positive trigger (google it there are plenty of easy diagrams).battery power for relays use the post port side of the engine when you remove the divider you’ll se the red cap use a ring terminal 

spilt the battery wire after a 15a fuse into 2 wires (1 goes to each relay) make sure they are even lengths . Ground the relays using the factory wire in each connector for underwater lights 

use each positive wire from the factory connector to trigger the relays 

there is a black wire with a male barrel conntector in the harness where the factory swim light connectors are use that for the ground wire to the lights I swing the same 1 into 2 split 

 

it will provide the same amprage to controller thus causing no issues and no ground loop noise 

I ended up doing most of the above minus the ground for the lights themselves. I ran those wires to the engine block where there were already two existing grounds bolted in. I'm sure I'll be fine but if I get a ground loop I'll try your idea. The lights work correctly when turned on in the menu so the only other testing that needs to be done is in the water with the engine running and the stereo on. Thanks for everyones help!

Link to comment
On 8/11/2018 at 1:56 PM, TexasTurner said:

Obviously I'm no expert but when I had this problem on my last boat I moved the ground from the motor mount to the negative terminal on the battery and the noise went away. I would say that your ground is the issue (ground loop) or you're running your power wire too close to your speaker wire, most likely the first one. That is why I asked if there was a grounding buss in the rear of the boat, otherwise I'll run my ground from the lights directly to the negative battery terminal.

Moved the ground up to the battery and no more feedback...thanks for the advice! The lights themselves have a high pitch noise coming off them that I hope will go away once under water. There is a good chance it is being magnified in a garage that echoes and close to the back wall. Going on a 4 day trip this weekend and will get a chance to really test them out.

Edited by vaporbluebu
  • Like 1
Link to comment
  • 11 months later...

Used this thread to do my install, it turned out great! I will say that I don’t think 2 relays is necessary for the draw of 2 lifeform 9’s. My wiring was pretty much based on the factory layout. 30/40amp relay from Amazon. Power from the stringer terminal at front of engine to relay “30” this needs a 10amp in-line fuse. You want This fuse as close to the battery terminal as possible. Cut one factory light harness leave the other alone, 2 blacks go to ground on the relay “87”, blue wire goes to the switch on relay “86”. 2 white wires from lf9 light get combined and can go together into one side of a heat shrink butt connector and those then go to “85” on the relay. The 2 blacks from lf9’s go the same way into a heat shrink butt connector and then go to the ground on the engine block. I used all 14awg wire with 14/16 blue heat shrink butt connectors and 2 3/8? Blue terminal ends with heat shrink. Fun project! http://imgur.com/FWKpoGQ

Edited by vinnvegas
Link to comment
  • 2 years later...
  • 1 month later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...