Expedition Air Susp "Chk Susp"
 

I just replaced the air susp system with springs & shocks. What a difference. I disconnected the electrical connector powering the pump. I thought this would prevent the chk susp light from coming on. Not so. I also got rid of front and rear electrical (sensors) that were connected to the front shocks and rear bags. The front sensor was in the way of my shock conversion. All I can think of is that I now have an open circuit or something. Any ideas on how I get the "chk susp" light turned off -- for ever? Thanks

my truck is aggravating me
 

I Have A 1997 Ford Expedition White In Color And I Put Some 23 Inch Tires On My Truck A Year Ago .. I Am Having Problems With It.the Back Of My Truck Keeps Lowering Down Giving Me That Very Annoying Bouncing... The Shops Have Put New Air Bags On It, Air Ride Sensors, Leveling Bar, And Now The Ford Company Says I May Need A Air Ride Module... If There Anyone Out There That Have Had This Problem Please Let Me Know What To Do Or If You Think You Know What Is Causing This Please Let Me Know...

Tt334

Saggin All the way down
 

I came out this morning and my truck rear was ALL the WAY down...

no light on instrument panel or any indication..

on ignition, I used to hear the compressor run for a few seconds.. now nothing...

where is the compressor located (pic please :)), and how should I go about troubleshooting.. I already inspected the relay and it looks good (under right front bumber)

No Air
 

You checked the relay but did you pull the harness off the relay---and with key off, jumper across the two terminals that have the two heavy gauge wires? When you do that the compressor should start---if it does it probably is a bad relay or corroded contacts at the relay. If it doesn't it's the compressor. If you jumper the contacts on the harness (and the compressor starts) with the engine running (and all doors closed) the rear should pump up (I think this shows the LLS computer is working properly--but not 100% sure)---if you shut down and quickly shut off the LLS switch under the dash on the pass side---it should hold rear air unless you have a leak and you can drive it for awhile. In my case the jumper with the engine running pumped her up and I just bought the relay and all is well---good luck

THANKS TRUCKER!!!

I don't have a bad compressor :)
I heard it working after I shorted the 2 heavy AWG wires, closed all doors, started, and wallah... Thar she blows... up up and away ..

my next step is to determine if it is the input to the relay or the relay itself... There are 2 inputs for the relay.. is that a sensor from each air bag? I assume they would be 12V(in) if the truck was NOT level, and 0V when it is level...

how often do the relays 'burnout', is this very common?

thanks again, you have saved me some mad dough!!

You have to pull the instrument cluster out and cut the power wire to the CHK SUSP. light...only way to get rid of the CHK SUSP light that I know of.

Lls
 

Boffah
Your situation sounds like mine---the compressor works but rear won't pump up---in my case it was the relay. The two small diameter wires in the relay harness have to do with the LLS computer in the dash. The far right one is a ground---the other comes from the LLS computer---it's what trips the relay to activate the compressor. You have two choices---buy a new relay at the dealer for about $104---an easy install----or replace the LLS computer in the dash which I would bet is a lot more expensive---since on this site the relay fails often, I'd reco you get a new relay or used at bone yd and hope that fixes it---If it doesn't then it's probably the LLS computer in the dash---be SURE all the contacts in the relay are not corroded and that the far right small wire goes to a good ground.

If the relay harness connectors aren't corroded---then the odds are it's the relay itself.

Hope this helps

anyone happen to know the pin outs of the relay?

since electrical parts are nonrefundable, I wanna know a way to test it...

PN F3LB-2C013-AA

I want to hook up 12V(?) to the main and jumper it to the 'gate' and make sure I see 12V on the output... (what are the other 2 thinner wires, are they both inputs from the height sensors.. and what should the voltage be when completely level, and low/turning on)

Thx again!! :-wink

something like this would help...
A Left Sensor (Active/low 12V, nominally/level 0V)
B Right Sensor (Active/low 12V, nominally/level 0V)
C Voltage in
D Voltage out to comressor