I recently purchased a 99 Expedition Eddie Bauer 5.4L with an aftermarket remote start system. It has the EATC climate control. When I use the remote start, the fans (front and rear) will blow, but it doesn't engage the AC compressor. All I get is hot air. I've downloaded wiring diagrams for both the remote start and truck, and the best I can tell, it's hooked up correctly according to the install instructions.

So my question is, is there something extra/different that needs to be connected to make the compressor kick in on the EATC trucks ?

 

The remote start has to energize both ignition circuits and the accessory circuit. Sounds like it's only energizing 2 out of 3.

 

Ok, cool. After looking at the wiring again, I think it's only energizing 1 ignition circuit, but I don't see a wire on the remote start harness for a secondary ignition. I'm going to have to research this some more. THANKS.

 

This vehicle actually has four ignition switch sections that are HOT IN RUN. Circuit # 1040 (Rd/Blk) is the one that also has to be hot in order to supply power to the WOT Relay which feeds the compressor clutch.

 

THANKS !!!!

Is there 2 rd/blk wires coming off the main harness over by the left kick panel ? The remote start's ignition wire is connected to a rd/blk wire. I forget what color wire the acces. wire is connected to, but I do remember the rd/blk wire. It's noticeably larger than the rest.

Do you know what other color ignition wire would need to be hooked into to make the EATC control temp an the fans blow ?

 

You need to add a double pole relay that is powered by the accessory relay output. You want to use the accessory relay output because the second ignition circuit shouldn't get powered during start, only run. Having too much come on at during cranking could create issues.

Also, do not tie the new relay to the remote start output in addition the coil leads for the existing accessory relay, you'll overload the output by powering 2 relay coils. You need to use the accessory output to power the 2 pole relay and use one set of contacts for the accessory wires and the second set for the second set of ignition wires. You cannot tie the new relay into the output of the current accessory relay because anytime the ignition switch is on the power will backfeed through the accessory circuit and power the new relay.

If you post the make and model number of the remote start we can be more specific in how it needs to be wired.

 

That makes sense...kinda. lol.

I have a Compustar CM6200 remote starter. The closest online manual I have found is for a Firstech CM6200. I think it's the same thing. The modules and wiring appear to be the same. The only major wire in the primary harness down by the steering column that isn't tied into the remote start system is a large gauge green/black wire.

THANKS again for the help.

 

That's probably the Light Green/Violet feed from F111 in the BJB that feeds half of the ignition switch.

There are three specific circuits that must be energized in order for the the A/C to run when remote-started:

1) Dark Blue/Light Green powers the PCM and rest of the ignition/fuel/engine management circuits. HOT IN START/RUN
2) Gray/Yellow powers the EATC module (does yours power up, I suspect not?). HOT IN RUN (#1)
3) Red/Black powers the WOT relay and the cluster.

Based on the instructions for your RS, I'd assume that the green wire from the 6P connector is connected to the DB/LG wire and the white wire from the 6P connector is connected to the either the GY/YE or the RD/BK wire. Can you verify what's connected where?

Alloro's suggestions are pretty much spot on except this can be done by adding a SPST relay only. Just need to pinpoint the specifics of what's needed based on what's already present.

 

Pin 9 White/Black on the 20-pin connector gives you your second accessory output. It gives a negative output so supply one side of a relay coil with +12 volts and once the engine starts the module will supply the negative to the other side of the coil to energize the relay and turn on the second ignition circuit.

If you prefer to have the second ignition circuit live during cranking use pin 7 Green instead. It gets wired the same way.

 

You guys are AWESOME !!!! I'll have to get up under the dash tomorrow and see what's what. But I do know there is a relay (looks to be SPST) wired into the system. I can that wrapped in the bundle of wires coming off the brain unit.

 

That could be the standard starter interrupt relay....

 

Sorry for taking so long to get back to this. Between work and the weather, this was the first chance I had to get under the dash. I just traced the heavier ga wire from the remote starter's brain. If I have to trace all the little wires, that's going to be a nightmare. They go deep into the dash. Here's what I found:

Brain green runs to blue/yellow wire on the truck harness
Brain red (both) runs to both light green/purple harness wires
Brain yellow runs to red/blue harness wire
Brain white runs to red/black harness wire
Brain green/white runs to the parking light switch. I think it's a brown wire

A small gauge white/black wire on the brain runs to a SPST relay I couldn't tell exactly which terminal was what on the relay, but a large gauge red wire from the relay runs to red wire on the truck harness, and a large gauge/blue relay wire runs to a grey/yellow truck harness wire.

However it's wired, the EATC has no power until the key is turned on. The fans run (front and rear), but there's no way to activate either AC or heat.

 

Bringing this thread back from the dead. I never did get this issue fixed, and didn't really stress it (until now), because I wasn't sure if I was going to keep the truck. Anyway, as time has gone by, I've decide to keep the truck, and now that it's almost 100F outside, I need the AC working. SO......can somebody simplify this for me, and tell me exactly how to wire this thing ? PLEASE !?!?!?!?!?!?!?

EDIT.....after looking at the install manual, I think my issue is with how Pin 5 (pg 13) is wired. However, I'm not exactly sure how to fix it. Do I wire in a separate relay piggy backed onto this wire (that is already connected to something), or do I need to run a completely new circuit (with relay) from another wire on the control box to whatever wire controls my secondary ignition circuit ? Or am I totally off on this. I've attached (I hope) the install manual for the remote start unit.

 

Why? If those two red wires were not connected to an ALWAYS HOT source, the remote start would never work. Double-check with a meter or test light to remove doubt.

Did you ever verify those connections I gave you 6 years ago in post #8?

 

I did, back then. But I can't remember exactly what was wrong. I do remember something was not as you described it should be. I won't have a chance to get back under the dash until next weekend, but I'll definitely be posting back what I find. THX !!!!!!!!