[TiTAN-]

Does anyone know the color of the headlight wire (low beam) coming from the combination switch to the BCM? For a 2006 if it matters.

I know the wire colors directly from the headlight to the IPDM... I need one closer to the dash preferably.

I've been looking through the service manual at the wiring diagrams for a 2011, but the wire colors should be the same, at least from what I can tell. The diagrams are slightly confusing.

If you don't know the color... but you have a service manual. It's in the EXL (exterior lighting), pages 79-80 (for a 2011 manual, but should be close if it's another year), connectors M18 and M28.

I think I have narrowed it down to a few possibilities. It says headlight 1 (real helpful, they couldn't do left/right?) is output 5, and headlight 2 is output 4. That would be terminals 8 & 9 for connector M28.

Another possibility is terminal 40 on connector M18, which is named 'CAN-L'. L as in low beam possibly?

Or it could be none of those...

Also an easier question... I need to know the polarity (+ or -) of the parking light circuit and the polarity of the headlight circuit. I believe the parking light circuit is positive, but I need confirmation? And the headlight circuit I assume is positive as well?

Any help would be greatly appreciated.

 

[BWV]

I would not apply power, nor ground to any of those wires between the combintaion switch and the BCM(m18 and m28)... your lighting and wiper system will suffer from it and you could damage the BCM.

As I understand it, this is a multiplexed scanning signal system. They use 10 wires to read the status of up to 20 switches. Timed pulses are sent from outputs 1-5, and read at inputs 1-5(a matrix) There are some diodes in the mix, I'm not sure just picking one of those wires will help you.

Don't touch the CAN-L wires, those are part of the vehicles data communication network. You don't want to go there without a dedicated CAN-BUS capable accessory.

I'm debating adding the DEI auto headlight system and have looked at all that real close. My solution will either be to go right into the HL switch itself with tiny wires and some relays to fake it to the BCM, or I'll go on the high current side by the underhood relays.
Havent decided yet.. lots of thinking to do.

Are you looking to turn them on with an accessory, or to send a signal to an accessory?

the EXL section of the FSM will explain the Scanning system...

 

[BWV]

I just looked at the 2011 manual you referenced... look on page EXL-18 for "COMBINATION SWITCH READING FUNCTION"

That section will explain it better than I do...

Edit: just looked for the 2006 FSM... I can only find the BCS section... If you have that FSM you can look on page BCS-3 ...it is exactly the same description as the 2011 and 2012 EXL-18page


I put a DEI 545T (Directed Electronics) Headlight control system in my wifes Mazda CX5 (same one I'd like to put in my truck).
Not knowing how their system works, but knowing there is a CAN bus that runs that whole car, and assuming a data system as opposed to old school switches, I opted to "trick it" into thinking someone actually turned on the light switch... so, as the light switch was only like 50 bucks if i screwed up, I elected to take it apart and see what I could see.
There were micro switches inside the switch assembly with little wires that ran to the connector. I cut the wires and put a couple DPDT relays in between so I could just take them over at the source, then used the DEI controller to actuate that relay. Works great.
I'm gonna pull the switch on the Titan soon and look it over... but its far more expensive if i make a mistake.. .so gotta be real careful.

 

[TiTAN-]

Thanks for the help.

That's exactly what I'm installing, the DEI 545T.

I figured I would have to tap into the headlight and parking light wires inside the IPDM. Connectors E123, pin 52 or 54 will work (left/right low beam, doesn't matter which), and connector E124, pin 57 for parking lights.

I just ran ~6 ft of 12 AWG through the drivers side firewall, through the engine bay to the IPDM. I'm just working on a way to seal the wires with the IPDM box so it's watertight.

The only thing I can't figure out is if the headlights and parking lights are a + or - circuit, for the brown and violet wires coming from the 545T relay. I've looked at the wiring diagrams in the service manual. They are both grounded and connected to the battery through the IPDM, (it appears anyway, electrical isn't my forte).

Do you know if it's a + or - switched circuit? I need to know for both the headlights and parking lights.

Or do you know how to find out? I've been looking at page EXL-79 (headlights) and EXL-107 (parking lights).

 

[BWV]

The positive side is what is switched by relays on both parking and HL circuits.

It looks like you are safe with feeding 57 for the parking lamps.
BUT..
I'd stay away from putting power on 52 or 54 as you will, if you put + power on it, be feeding the IPDM CPU a + signal(and voltage/current) when it is not expecting to receive it. You may have unpredictable results.
I don't know if they do that for monitoring for bulb outage or to prove relay closure, or what...but there is a connection from 54 to the CPU. (and 52 by way of them being tied to the same relay output) I get nervous about that stuff.

If you do only hook 52 or 54, and dont get wierd computer stuff going on, that will still only give you auto lamps on your low beams.. if you flip to high beams you will still only have low unless you turn on the switch manually.

I'm not brave enough to hook that side of the circuit(the IPDM) for fear of cooking the expensive bits or nickin' the wrong wire... and after readin' up on it, I will opt to hack the actual light switch like I did on my Mazda. If I burn that... its hundred and fifty bucks and not thousands.

 

[BWV]

I posted pics of a disassembled switch in a new topic here
I'm going to solder onto the traces on the PB board inside the switch housing with some fine wires and run those to some small relays to imitate turning the lamps on at the switch. This needs 3 separate switched poles

I have decided to make my own controller for the Titan headlights out of a microcontroller and some other bits.
It'll do the same thing as the DEI 545 when I'm done, except I'll be able to control when the lamps turn on, and when they turn off independently, as well as control independent on and off delays. I might even use it to sense wipers (the dei has this), as NY is a "wipers on/lights on" state.
I haven't built it yet..just ordered parts and thinkin' about what features I want to build in...