Canadian daytime running lights questions

[Ωhm]

On 5/23/2023 at 12:45 AM, 91Pioneer said:

Is there a good place to tap an ignition-on wire near the LF headlight area?

 

4_0L Engine Harness pg90.pdf

 

Between C100_B6 and C103_E runs a YELLOW (14awg) wire. This wire should be IGN SW I1 feed.

[91Pioneer]

4 hours ago, Ωhm said:

Between C100_B6 and C103_E runs a YELLOW (14awg) wire. This wire should be IGN SW I1 feed.

Thanks. I did some wiring today, made some great progress. I'm being super picky so it's taking a long time LOL I'm trying to make it look pretty darn factory.

[91Pioneer]

An update -- so I got the wiring soldered up (mostly). I am using the dual aftermarket relays to handle powering the headlights, and I wired up a factory DRL relay from a '90 CDN XJ.

 

By using @gogmorgo's tip of putting the DRL output wires on the other side of the relays the high beam indicator works as the factory intended without me needing to wire up the high beam DRL wire.

I ran into a few snags during testing like a bad relay out of the box and a bad connection at the headlight, but now I'm ready to tidy up the wiring and actually install it in the truck.

 

Here's a pic of the T-harness that I created. I am drawing ignition power from the main wire bundle going past, I am grabbing battery power direct from the starter relay for the 2 headlight harnesses, and the DRL relay gets power from the 10-pin harness power wire. Grounds will go to the existing bolt on the inner fender by the washer bottle.

 

So far so good. One thing I'm left wondering is how to hook up that park brake wire that turns off DRLs when the park brake is engaged. I was looking at the wiring diagram and it *appears* that I can tap that wire into the grey/black wire at the proportioning valve and that may work. Otherwise I will have to run that wire all the way into the cab at the park brake somehow. That part of the wiring is unclear to me still.

 

Just for reference the wiring on the right side of this pic goes inline at the 10 pin headlight harness.

 

[Ωhm]

If the DRL module wire used for LAMPS OFF with PARK BRAKE being applied is looking for a path to ground, then using the grey/black wire at the proportioning valve will work for you. NOTE: Path to ground will also be made when proportioning valve has been shifted (brake issues) or when IGN SW is in the CRANK position (bulb check).

[91Pioneer]

2 hours ago, Ωhm said:

If the DRL module wire used for LAMPS OFF with PARK BRAKE being applied is looking for a path to ground, then using the grey/black wire at the proportioning valve will work for you. NOTE: Path to ground will also be made when proportioning valve has been shifted (brake issues) or when IGN SW is in the CRANK position (bulb check).

I don't know what the park brake DRL wire is looking for, ground or power? I'm afraid to just put power to it or put it to ground as I don't want to fry it, I desperately need it to work for the safety inspection (the DRL function, not the OFF feature). The park brake wire has a diode in it, I think it's called.

 

It had not occurred to me that the DRL should be off during cranking 

[91Pioneer]

I added "factory" DRLs to my US-spec MJ and added the aftermarket headlight relays. Project is done the only odd thing is the DRL output is just under 2V per headlight, they seem a bit dim but as long as it passes inspection I don't care.