Switch Panel / Switchpros Install Underhood Tap Points

[psnyman]

Hi @Julian73 - I also have a 2016 LC and wondering if you wouldn't mind sharing/DM a summary of the fuses you've tapped into please? I'm looking to find the low beam or parking lights. All the other diagrams shared don't match the 2016 LC and your is the closest I could find.

 

[Julian73]

Hi @Julian73 - I also have a 2016 LC and wondering if you wouldn't mind sharing/DM a summary of the fuses you've tapped into please? I'm looking to find the low beam or parking lights. All the other diagrams shared don't match the 2016 LC and your is the closest I could find.

IGN + ... 2nd Column from left above Blue 'DEF' Relay. This is a blank but active socket So I only needed a fuse in the upper Tap slot. (FYI Column 1 & 2 are all IGN1 circuits, Column 3 & 4 are Battery +)

High Beam .. 2nd column to left in upper fuse box (sector between the fuse bars that look like memory cards). Use either socket 1 or 2 up from bottom. However, I could only fit the tap in 2nd socket labeled H-LP LH-Hi due to ridge in housing. Socket code H-LP = Head Lamp, and Left Hand /Right Hand Hi beam.
Low Beam .. 2nd Column from left Use socket either 4 or 5 up from bottom; I used #4 so that I was taping one left headlight Hi and one right head light Lo, so in event of a tap failure I would be able to have one working bulb on each side of vehicle.

ACC .. was taken from Fuse Box J4 under dash on LHS ( at least on Left hand drive cars). I found Column 1 on left, 7 sockets up from bottom: Slot SFT LOCK-ACC, to be active but unused.. Positive + rail is on the right.

The positive side of these socket in towards the center of the two column pairs. This is important as the tap-a-fuse pig tails must leas away from this in order to protect the circuit correctly, while the polarity makes no difference to the lower fuse slot which is the original circuit protect, the upper slot must be powered from the position leg so that the current goes up across fuse 2 and out the wire to the load. If plugged in backwards, power goes up the (neg) leg, across the original circuit fuse 1 (perhaps doubling the power through the fuse and nuance tripping it) then up the leg to fuse 2 and out power lead. Thus a blown fuse 1 (lower) will take out both circuits. If Both 1 and 2 are 10 amp fuses on typical 6 amp load circuits, then with both loads active fuse 1 will see a continuous 12 amp load and will always blow and take out both functions.

 

[Drift Monkey]

One can drive the bulbs via splicing into the wires on the tow receiver if just looking for parking parking and brake lights.

I’m looking at doing this and leaning towards LED 7443s for parking/brakes and am researching the best way to tackle this.

I don’t think one can just splice into the tow harness for the brake lights since they are combined with the L/R turn signals on the 7-pin.

It seems like a 2-3 converter can be run, but with the unintended consequence of the hazards also triggering those brake lights to flash since L+R signals on together is interpreted by the converter as brakes on. Not sure how I feel about that.

The other solution is to tap directly to the brake lights but I haven’t looked at how hard it is to snake a wire through the body into that rear fog area.

 

[grinchy]

I’m running the converter. I use a trailer /tow breakout box, aside from the install time inline with the tow connector, it makes wiring accessories easier.

 

[Drift Monkey]

I’m running the converter. I use a trailer /tow breakout box, aside from the install time inline with the tow connector, it makes wiring accessories easier.

This makes sense, but it doesn’t solve the turn/brake limitation of the 2-3 converter, right?

 

[grinchy]

This makes sense, but it doesn’t solve the turn/brake limitation of the 2-3 converter, right?

Nope. To do that you’ll have to tap into the source signals somewhere. Flashing red vs flashing yellow when on hazards (and car alarm set) wasn’t a huge issue for me.