This is great stuff -- thanks!!!
I've been doing a bunch of research, and at this point I don't like the idea of installing the new center light in the liftgate. Problem is, the light has an electronic (vs. mechanical) switch, so it always defaults to light on, at brightest intensity, when the liftgate is opened. So I need to always remember to turn it off when I open (and leave open) the liftgate during the day. (And not just me -- if I'm camping with friends or my girlfriend, they also need to be careful to always turn off the light.)
But on the positive side -- the center light seems to work great, it's easy to turn on or off (just touch it), and has full intensity range control. AND -- per BoredomFestival, the liftgate is pre-wired for the light -- no need to run any wire. (Not sure if this is for LC LC only, or for the 1958 as well). I'm guessing that the plug that he used was pre-wired to support the optional factory-installed liftgate lights. If so, then there won't be any automatic timed shut off (which is the problem with the factory-installed lights). Alternatively, if you install the center light using the supplied wiring harness, it sources the power at the driver's side cargo light, and I think that is on a timer to turn off after 20 minutes.
So far as my situation is concerned, even if I decide to install the center light, I still need to remove the liftgate interior panel in order to disable the OEM lights. Given that, I think that overall, the switch installation is the best bet. I'll never have any reason (that I can foresee) to turn the light on during the day, and thus, I needn't have any concerns about remembering to turn it off during the day. Generally, I would always keep the light switched off, and I'd only use it occasionally at night (usually I wouldn't even need it since I'm wearing my headlamp). So (relatively) no worries.
Regarding your recommendations for the switch installation...
- I agree, I will only do a simple switch on/off function (and not hook up the switch light). In this case, the ground wire to the switch should not be necessary, right?
- One of my main concerns was finding the correct splice point, but it sounds like this should be pretty straight forward, since my understanding is that there is a simple two-wire run that is upstream of the factory Y connector (that splits the circuit out to the two lights), and I just need to connect the switch in just upstream of that. In that I'm not powering the light on the switch, presumably it shouldn't even make any difference which of the two wires I cut and route to/from the switch.
- My other concern was how hard it might be to remove the liftgate interior panel. Since it's large and overhead, it will for sure be more awkward and difficult than removing something like a door panel. Were there any gotcha's or lessons learned from when you pulled yours off?
One thing I am still confused about -- I do not understand the usage of the Positaps that you mentioned (nor did I understand their apparent use (circled) in the photo you provided). My understanding is that, per your wiring diagram, I'm just going to cut one of the two wires upstream of the Y connector, and then route that wire to and from the switch. So rather than
tapping into anything, I need to make two wire
connections (i.e. the red wire to the green wire that runs to the switch, and the other side of the red wire to the green wire that returns from the switch). A Positap allows you to
tap into an existing wire (thus making a T connection) -- but I don't see any use for that here. Am I missing something?
Sorry for the long response here! I really appreciate your help, this is a pretty important problem for me to rectify. I think this info may be useful to others as well, as I know that there are a bunch of folks trying to sort out the optimal cargo area lighting solution.