How to trigger running board lights and interior lights on '98 Expedition?

[AGrayson84]

Hi everyone! I own a '98 Expedition XLT.

So my truck came with a factory keyless entry/alarm. I just finished installing a Code-Alarm CA6552 which is keyless entry/alarm/remote start combo. None of the wiring that I did for the new system tapped into the factory alarm. I went directly to the door lock and unlock wires in the harness going through the firewall, and now when I unlock the car I no longer get the illuminated entry (running board lights and interior lights) that I used to get with the factory alarm. The new system has a feature to for illuminated entry via the Aux 1 output, and can be set to trigger these lights when unlocking the car and shut them off after 30 seconds or once the ignition comes on (whichever comes first).

What is the easiest way to regain this feature? Is there a single wire in the factory alarm that I can tap into that will trigger the running board lights and the interior lights? Or do I need to tap into those individual wires elsewhere? I know I'll need to get a power source, fuse, and relay to convert the negative pulse on the Aux 1 output of the new system to a positive power supply, but I just need to know which wire(s) to tap into and where to find them. No diagrams that I have come across provide any information on these wires. Any help would be hugely appreciated!

 

[stamp11127]

You'll need the wiring manual for your 98. On my 99 it shows two relays - one for the interior lamps and the other for the running boards. Both of which are controlled by the GEM.
Easiest way is to find out which set of wires controls the coil on the relays. Disconnect that portion of the GEM and wire in your new alarm to the coils.

 

[Thermo]

aGrayson, what part of SoMD are you in? California here.

As for your problem, you will need to tap into 2 places if you want your running board lights to come on. If you are only after the interior lights, then you simply need 1 wire.

If you are only after the interior lights, then you will need to find the orange/light green wire on the back side of the headlight switch. You will need to tap into this wire and when you want the interior lights to come on, you will need to ground this wire. So, you will have to read in your alarm manual on how to do this.

If you are wanting your running board lights to come on too, then you will need to do the orange/light green wire update, but now you will also need to located the light green/orange wire running between the PPO relay block and the GEM Module (probably easiest to locate the GEM and access the wiring there). You will need to tap off of this wire and ground it too when the system engages the interior lights. Please keep in mind that the relay to power the running board lights is powered off of the interior light system. So, if you only do the running board light wire, you will not get any running board lights.

 

[AGrayson84]

aGrayson, what part of SoMD are you in? California here.

As for your problem, you will need to tap into 2 places if you want your running board lights to come on. If you are only after the interior lights, then you simply need 1 wire.

If you are only after the interior lights, then you will need to find the orange/light green wire on the back side of the headlight switch. You will need to tap into this wire and when you want the interior lights to come on, you will need to ground this wire. So, you will have to read in your alarm manual on how to do this.

If you are wanting your running board lights to come on too, then you will need to do the orange/light green wire update, but now you will also need to located the light green/orange wire running between the PPO relay block and the GEM Module (probably easiest to locate the GEM and access the wiring there). You will need to tap off of this wire and ground it too when the system engages the interior lights. Please keep in mind that the relay to power the running board lights is powered off of the interior light system. So, if you only do the running board light wire, you will not get any running board lights.

Well, howdy neighbor! Haha California here too, pretty much. Our zipcode is a Great Mills zipcode, but I currently live in Hickory Hills, just right down Chancellor's Run Rd. Small world! Not sure why I've never seen your Expy around here.

What's the "update" that you speak of? Thanks for clarifying about not getting the running board lights if I don't trigger the interior lights as well. I probably would have never figured that out and gave up when trying to make sure I'm feeding power to the correct orange/light green wire.

Have done any off-roading in your truck? I was planning for a lift and 35" tires... but then I wanted an Eddie Bauer to do it to, then realized I'm now 29-years-old and will probably just get an '05/'06 Navigator later this year and not do the off-road thing to it. Getting old I guess lol.

 

[AGrayson84]

You'll need the wiring manual for your 98. On my 99 it shows two relays - one for the interior lamps and the other for the running boards. Both of which are controlled by the GEM.
Easiest way is to find out which set of wires controls the coil on the relays. Disconnect that portion of the GEM and wire in your new alarm to the coils.

Sorry Stamp, I didn't even see this post somehow the other day. Thanks for the help, as always! Any idea whether the relays use a negative trigger or a positive trigger to activate these lights? My new alarm has a negative (-) output for illuminated entry, so if the relays for these lights use a positive trigger then I'll obviously need to wire a new relay for the illuminated entry output of the new alarm.

I have a Hayne's and Chilton's manual somewhere for the truck, just not sure where they ended up at haha.

 

[stamp11127]

I'd have to look back at the diagrams after I get a good nights sleep. Had a rough day in the land of stupid today.

Easy way to tell is with a voltmeter or test light. Does the coil have power with the lights off? If so, it is a negative trigger.

 

[AGrayson84]

Haha I understand exactly what you mean Stamp, how you were able to get some decent rest.

I do have a voltmeter and a test light, but not sure where to find the coil for any of this stuff. I did find the light green/orange wire (for the dome lights) in the passenger kick panel yesterday, and that wire was only hot when the doors were open, so I guess that answers my question about that wire.

I think I'd rather locate both the dome light wiring and the running board lights at the GEM, rather than running a wire or two over to the passenger kick panel of the truck. So from what I read yesterday, the GEM is attached to the back of the interior fuse panel? I couldn't find much about it on Google. Do I just remove the four 10mm bolts that look like are what holds the fuse panel in place, or what does it take to access the GEM? Thanks again!!!!

 

[stamp11127]

The coils are inside each relay. Pins 85 & 86 are primary pins 30 -87/87A are secondary (heavy load).

Haven't had to remove my GEM yet so this is from a manual:

CAUTION: Electronic modules are sensitive to electrical charges. If exposed to these charges, damage may result.

Disconnect the battery ground cable.

Remove the steering column opening cover.

Remove the bulkhead electrical connectors from the instrument panel fuse junction panel.

Remove the instrument panel fuse junction panel bolts and remove the interior fuse junction panel nuts.

Disconnect the GEM electrical connectors from the GEM.

Remove the screws and the GEM.

 

[Thermo]

AGrayson, it is a smaller world than you are thinking. If you continue straight for the light for Hickory Hills, make a right at the next road. I live back in Greenview Villas. If you drive back there, you will see my truck sitting there on the right. It is tucked back there a little bit, but it is there. Once you see it, you will know it is mine.

As for why you don't see my Expy is because I am not driving it much now. I spend most of my time driving around in a Jaguar (easy to spot mine as it is the dark green with the non-chrome corners and the rear of the car has "JAGUAR" in chrome-I am the only one I know of with that combo).

if you need help getting the light working, let me know. I am a little busy until the end of March (working up at the nuke plant and I am in the middle of an outage), but after that, I will have time to play.