LR4 firewall access for a cable

[Flocker]

I am attempting to run a single electrical cable from the engine bay into the cabin (to connect a hardwired radar dector system required by the heated windscreen, which renders typical radar dectors nearly useless).

I can't for the life of me figure out how to get the cable into the under-dash area.

With all the dual battery systems and aux lighting available for these trucks, there has to be a way, but the wiring loom grommet under the brake booster looks packed beyond capacity as it is.

Any ideas would be appreciated, and I'll try to do a write up if I can figure this out. Thanks in advance!

 

[umbertob]

There was an unused grommet on my NAS 2013, on the firewall behind the aux. battery compartment found on the driver's side of the engine bay. I popped that plug off to run an electrical cable from the Traxide dual battery management kit and auxiliary battery I installed in that compartment, all the way to the rear cargo space for extra 12V outlets there. For point of reference, look at the driver's side windshield wiper motor, that grommet would be approximately 4-5" below that motor on the firewall... I tried to take photos of it before, but with all the brake lines and crap in the way, I couldn't. It's a PITA to reach once you find it as well, even if you have tiny hands... I used the shaft of an extra long and skinny screwdriver to both pop the grommet off and kinda wedge the electrical cable through and into the cabin (well above the brake pedal area.) Don't know if that's the same grommet you are referring to, on the 2013 it was unused but on a 2014 with the new extra battery in there... who knows.

My radar detector works OK behind the windshield. The part that has trouble locking in sometimes is the built-in GPS (Passport 9500iX), but radar / laser detection seems to be unaffected by the heated windshield.

 

[Flocker]

Wow, thank you for helping me out. I will look there and enlist the neighbor boy to get this hand in there if can find it . Mine's a 2011, so should be the same.

I am fascinated (or worried that I am wasting time ad money) by your experience that the windshield didn't interfere. Could the screen be different in 2011 and 2013? I also had a 9500ix (what an awesome product, btw). But when I bought my LR4, the range was cut so significantly as to be worse than nothing. After calling Passport and LRNA, I was told that is was out of luck. I was so bummed as to consider replacing a perfectly good windscreen. Check out this quote from Radartest.com's review of the Passport 8500:

"Others, like Jaguar, Range Rover and Land Rover, for instance, offer heated windshields with a fine wire mesh laminated into the glass. In a recent test we made the mistake of using a Jaguar XJ Supercharged for the target car and were baffled when none of the 11 models could detect most of our radars from more than a few hundred feet away, rather less than the six miles of range (and over 14 miles in the case of one model, a world record) they'd demonstrated in a previous test. Only when we closely scrutinized the windshield did we note the nearly invisible heating element wire mesh. But it's a safe bet that an XJ driver could've driven a lifetime without noting the detector's supernaturally quiet operation."

I will hopefully have both my 8500ci and 9500ix for a while before I try to make one of my friends buy it, so I will report back.

 

[umbertob]

I have experienced no issues with the range of the detector personally, but the occasional failure of the built-in GPS receiver (reception seems to be sporadic and dependent on time of day and location, which drives me crazy) to lock on the birds does cause false radar alarms, like with my old Valentine 1 - one of the main reasons I switched to a GPS-aware detector to begin with, I was very happy with the performance of my trusty old V1 otherwise. FYI, I mounted mine low on the center of the windshield, about an inch or two above the dash center channel speaker. Don't know if that makes a difference or if my heated windshield is different than yours - I doubt it, but who knows for sure. Let us know how it goes. It's good to see Land Rover is now making regular windshields a NCO on their newer models with cold weather packs. Here in SoCal, I don't think I have taken advantage of those heating filaments sandwiched in the glass panes once, but I would hate to give up my heated seats to get rid of the metallic thingies in the windshield.

 

[nwoods]

On the LR3, that spare grommet under the spare battery tray (and brake booster) was a bit of a PIA to get into. I found it much easier to run a primary cable through the steering column grommet, and then set up a BlueSea fuse block under the dash to tap into for all my secondary needs.

 

[Flocker]

umbertob-

Thanks for your advice. found it. it was a total pain to rout the cable blindly. My passport 8500ci is in and hooked up (im embarrassed to say how long it took me). I got a decent pic of the grommet, that i'll post to this.

 

[ar4me]

Does anyone have a picture of the grommet?

It seems some say under the brake booster while umberto's description would indicate it is to the right of that (looking at the firewall from the front). I see the grommet with the main harness going into the cabin, and a bit below that, what appears to be the hood release cable. Where is the available spare grommet relative to this?

 

[Derel1cte]

Why go through the firewall at all? Just use an Add-A-Circuit in you passenger compartment fuse box and run a wire up the a pillar cover into the headliner.

I literally did this earlier today so that my ipad would charge when the truck is off. I tapped into F1 (Map lights) behind the glovebox since it has constant 12v.

To prevent the battery from completely draining if I left it too long, I wired in a off time delay circuit so that the socket will have power for 45min after turning off the truck.
http://www.amazon.com/gp/product/B015Z2EQCU
Here it is doing a little testing and programming of the delay time. The red connector is the constant 12V that supplied with the add a circuit. The blue connector is the signal that I spliced into the wires for the cigarette lighter. This wire is split so that it powers one 12v socket lick normal (only on with ignition) and acts as the signal to supply power (on) and start the countdown (off) for the second socket. Yellow is ground, also spliced into the cigarette lighter.


I wired them to some 12v sockets behind the dash so that i could use some usb adapters with iQ for detecting wattages and whatever. Seemed easier to have a couple hidden plugs behind the glovebox than to hack up the power adapters and direct wire.

If you are looking to wire the radar detector so that it is only on with the ignition it is even easier. Just tap the fuse for your cigarette lighter or any of the dozens of on-with-ignition fuses you'll find in the passenger compartment fuse box.

 

[ar4me]

Why go through the firewall at all?

Power from secondary battery to cargo area (traxide kit)

It's definitely not under the brake booster. More to the outboard side (driver side) of the brake booster. Shine a flashlight around by that area and you should see it.

Thanks! Hmm, I looked and had my wife look as well. Below or above the grommet with the "main harness", further towards side or center of car? I see a little grommet lower and outwards, but it hosts what looks like the cable for the hood release...

 

[unseenone]

Yes, go to the traxide threads, there are pictures there.. That will help a lot..

 

[ar4me]

Thanks guys! Found it this morning Just above the main harness going through the firewall on the right of the brake booster, looking from the front. The traxide thread does not have any pictures or good description, unfortunately - at least where I looked, maybe I missed it. Anyway, mission accomplished

 

[unseenone]

Sorry, there was a link to my gallery in a couple of those threads with the pictures. Glad you found it. When you feed through, leave the grommet, just cut the smallest hole possible and run the wire through the grommet and fit it back. Use a screwdriver to push through the firewall. Then with a helper feed the grommet back in and fit it. Gallery.

 

[ar4me]

Nice pictures Thanks. I ended up taking out the grommet, on the bench use an awl to poke a hole and thread the wire through - a tight, snug fit, and fed the wire with grommet towards, and through, the firewall hole. To re-seat the grommet properly I took out the metal wire guide for the loom running along the top and right side of the brake booster. That gave just enough room to get my hand to the grommet hole and wedge it into place... whew... was still a major PITA. On the LR4 there is the additional fun of relocating the transfer case control module...

 

[iowalr4]

I have a passport 9500i and I dont use it in my LR4. 1. I drive slow in my LR4 and 2. I do think the radar detector has issues behind the heated windscreen. The GPS also is super flakey.

It's a great detector though. I should probably sell mine.

 

[unseenone]

:wavey: I've never gotten out of that one without bruised and cut knuckles... Glad it worked out..