My
rearend is down and I don't hear my compressor run
If
you have an intermittent check suspension message, the absolute best way to find
out whats wrong is to pull the code(s) from the module. Unfortunately, most of
us don't have access to a $2500+ scanner to do this.
NOTE:
ESPECIALLY IF YOUR VEHICLE IS A 4X4, INSPECT THE LINE
UNION THAT JOINS 2 AIR LINES TOGETHER UNDER OR SOMEWHERE AROUND THE BRAKE
MASTER CYLINDER.
This line
union is about 1 inch long and black in color. It maybe hard to find because its
the same color as the air lines protective sleeve(the actual air line is the white
part inside the black protective sleeve) and will be dirty just like everything
else under the hood. Use a flashlight to locate & inspect this. When you locate
the union, twist it on the air line and check it all the way around. If it is
bad, you'll see a crack going down the side of it.
When
this line union splits, it will cause a leak, but if they split bad enough, one
line will pop out of the union completely and its impossible for the compressor
to build ANY pressure. This means all the air in the rear air springs will be
vented out as soon as the solenoids on each air spring open up. 4x2 models can
have this problem also, but we get a 10-15 to 1 ratio of 4x4 calls over 4x2 calls.
If
the line union was broke and a line had popped out, replace the line
union and try disconnecting the battery for 30 minutes before trying it out.
Theres a good chance that you'll need to have someone with a compatible scan tool
to erase the code(s) it caused.
If the
line union was not the problem, I would check the compressor for power at the
BIG RED wire on the harness side of the compressor
connector right after turning on the ignition. The connector I'm referring too
is has 4 wires in it and the colors are:
1
Big red wire (power to compressor motor)
1
Big black wire (ground for compressor motor)
1
White or Yellow wire (ground for vent solenoid)
1
Blue wire (power for vent solenoid)
Remember
to check this wire as soon as the ignition is turned on and give up on it after
about a minute. After this minute has passed, turn off the ignition, then on again
and check for power once again. The module will only try to turn on the compressor
for around a minute before it gives up. If
you aren't getting power to the compressor, it is possible the relay is damaged
inside, because it s solid state relay, it can't be revived and needs replacing.
Before replacing the relay, try
one last thing before shelling out $110-$130 at the "stealership".
Check for corrosion on the air suspension compressor relay connector. The location
Ford chose to put the air suspension compressor relay is not the best possible
place for an electrical part, but I think they put it there to help its ability
to cool itself.
NOTE:
The compressors
that these types of relays provide power for are power hungry. In other words,
they are the biggest of the Ford/Lincoln group and "draw" or "pull"
allot of amps even when brand new. This same compressor with some time on the
clock can eat a relay for lunch!
It
is located in the RF fenderwell up high, like behind the headlight housing. It
is (see pic above) black & aluminum in color with cooling fins. First unplug
the connector and inspect the contacts. Even if it "looks" clean, while
your in there, go ahead and clean the contacts with an eraser and wash any contaminates(grease/oils)
away with electrical contact cleaner and put some dielectric grease on the contacts.
Blow dry with compressed air if you have access to an air compressor.
I
have had several and heard of many more that had no signs of corrosion, but came
back to life after 10-15 minutes of TLC.
PARTS
- AIR
SUSPENSION HELP
