H3 Yet Another LED Light Bar Thread! Also Fixed Roof Marker Lights

[lugantom]

Why, you may ask, would someone post another thread about how they installed a 50" LED light bar from G2 LEDs on their H3? Well, a few reasons:
1) I also fixed my roof marker lights, and I'll describe that here at some point
2) I did a lot of extra work to review wiring diagrams and connect to the factory fuse box (no loop connectors at the battery)
3) I used the factory dash switch, which I think looks pretty cool
4) I ran into a lot of little, annoying problems that I thought others who attempt the project might want to know

As I have time, I'll try to post all of the detailed pics. Here's an overview:
1) Reading this forum, I decided to abandon my original idea of integrating light bar mounts into sheet metal mounts of the marker light valence that goes over my windshield
2) I found out that G2 LEDs has a big sale on their package - 50" bar, wiring harness, and their mounts and mounting kit; so I bought that
3) Instead of using the provided harness (which arrived over 1 week later anyway), I made my own connections to the factory fuse box using wiring diagrams that are available on the web in pdf format for free
4) While doing the wiring, I realized how horribly the "factory" installation of the marker lights was. VERY poor workmanship. I fixed it, but in doing so had to add another splice into two 18 gauge wires. Not a big deal to have another splice, just made me mad.
5) Had a TERRIBLE time with the provided rivnuts. My advice, despite having installed a Yakima rack many years ago onto my Ramcharger and another one onto our minivan using rails and Yakima's version of rivnuts - DON'T FOOL AROUND with little nut, bolt, and washer set-ups trying to compress the rivnuts. Just borrow or buy the !%$#@! tool (mine is basically a big rivet gun) and set them with it. Would have saved me HOURS of furious cursing and fretting.
6) All my fears about clearing the marker lamps with G2's mounts, etc. were for nothing. Went on great. One weird thing - the passenger side wiper blade smacked the fins on the back of the bar at the top of its swing. My wiper blades are an odd design, so I just cut some plastic off the end. But, next time I buy new wiper blades, I'll have to check to see if there's a clearance issue with more standard design wiper blades.
7) Right now, there's still a bit of whistle coming from the bar. Maybe that's what the Monsoon amp is for, but I do think I'll play around with bits of vinyl or rubber to try to dampen and silence the noise.

Bottom line - VERY nice to have a clean look that I think enhances the vehicle, and to have the safety of being able to throw amazing light ahead of me on any dark road. If a deer manages to get in front of me at night, it will have to be a very resourceful deer.

 

[woodwardsh3]

Do you get a lot of glare or reflection in the windshield?
Look good.

 

[RamRod]

To fix the final noise I just put high temp silicone between the fins in three sections and never heard a peep again.

Looks good!

 

[lugantom]

No glare or reflection.

I'll try the silicone!


Sent from my iPhone using Tapatalk

 

[lugantom]

More Detail on the Marker Lights

OK, I have a few minutes, so first I'll add more detail on the repair to the marker lights, since others had a similar problem. The sort of rivnuts that GM uses to mount these accessories come loose. As a result, when someone changes the windshield, if they don't care, they don't put the fasteners back on correctly. If you hear a rattle - FIX IT. I didn't, and one day while cruising down the interstate the valence tore loose. Fortunately, one end held, so I was able to hang onto most of it. When I got home, I damaged the valence further trying to remove it while those nuts kept turning.

Finally, I took the time to repair the valence and repair the nuts. I asked a local body shop to spot-weld. They did a pretty nice job - put a bid of body filler around their weld spots. I then spray painted with a color matched rattle can (not really necessary, since it's under the valence, but I had the paint, so ...).

I had to repair the valence. I used Epoxy to put back together the fastener anchors that tore loose, and used some 3M vinyl mastic to build up a support to replace one of the two supports that blew away the day the valence tore off.

Once that was complete, I used some black RTV for better sealing, some matching metric thread bolts, and re-attached the valence to the now-secure nuts. Unfortunately, I lost some caps and others didn't fit after my repair job, so I used some 3M vinyl mastic to cover over the bolt heads. I did notice that the original installation was poor. The holes aren't positioned correctly, so that the passenger side is about 1/8" forward of the driver's side. Unfortunately, so good way to fix that.

Later, when I went to add my light bar, I noticed how poorly the wiring had been installed. A single unprotected wire was kinked and pinched under the fuse board. So, while I was connecting for the LED light bar, I also fixed the wiring for the marker lights. I fixed the connection at the fuse panel and put that entire wire in the looming, and re-routed the other end to go inside the fender instead of being pinched under the little faux air inlet:

 

[lugantom]

Wiring the LED Light Bar

G2 LEDs provides a pretty high quality harness with their light bars. However, I don't like the idea of adding loop connectors to my battery or in-line fuses in my wiring harness. So, I figured, even before G2 failed to supply the harness the first time around, that I'd see if I couldn't wire directly to my fuse box for a more factory look. The light bar had a 288 watt rating, so I planned on a 25 or 30 amp relay and fuse.

I found the wiring diagrams for the H3 on-line. I found that positions 2 and 10 are typically used for the grille-mounted lights, so I decided to follow that set-up. I learned a few key things

1) I also found the factory push-button switch for accessory lighting and its harness available e-bay (got the part numbers from this message board):

2) The wires from the diagram, though unused, are still present through the firewall. I matched the colors, confirmed with a continuity check, and was all set to wire the relay for my light bar to match the factory set-up for the grille lights:

3) I pulled the fuse panel, figured out how to manipulate the huge connectors, and used the continuity checker to find which wiring locations were fuse 2 and fuse 10. Here's where I had my major surprises. First, I had a REALLY hard time getting the fuse panel and its connectors back together. I finally figured out that I had to connect the large wiring connectors to the fuse panel FIRST, and only THEN could I get it back into its box and latched. I realized that the guy who wired the marker lights didn't figure that out, and he broke a lot of the plastic (including the tabs that hold the cover down, which explained all the dust and dirt on my fuse panel). The other big surprise was that, yes, I found the connections for fuse no. 2 and fuse no. 10. What I failed to do was verify that ALL of the unused fuse locations had power TO them, not just connections FROM then. So, when I reassembled, one of my output wires was hot, but the other was NOT. Very annoying. Took me hours to bend little connectors to fit inside the plastic wiring connector, all to find out that I was connecting to a dead position. But, ultimately, not a big deal, since it was never really clear why GM ran one fuse to the to for the switch and a separate fuse for the hot to the relay. I just did what most people do - spliced the single hot wire to feed both the switch and the power to the relay (off fuse no. 2 - the one that DID have power):

After that, the only bit of tedious work was routing the looming. I found that I could easily chase a wire under the faux air intake (which pops right off); so I routed the wiring through that path from the relay to the light bar. I waited for G2 LEDs supplied wiring harness only so that I could cut off the nice weather-sealing plug that they provided.