Lincoln/Mercury Repair: lincoln navigator air suspension, compressor failure, system diagnosis

Question
I have a 2001 navigator and the rear end is just about sitting on the wheels.  The dealer said over the phone it is a min. of 1000.00, but probably 2000 (yes, thousand) to fix.  This "t" fitting, does it have another name, such as compressor valve and can it be repaired at a non dealer shop?  Thanks

Answer
Hi Rene,

Actually, I spoke with my buddy that did mine and he said it was a connector. They just followed the lines and found the connected that blew off and purchased the part at Ford.

I found this TSB though that was interesting. Article Number 03-9-2. If you look it up online you should be able to get pics with it. I copied what I could here below:

Article No.
03-9-2

05/12/03

^ SUSPENSION - REPEAT AIR SUSPENSION COMPRESSOR DRIER FAILURES

^ ELECTRICAL - REPEAT AIR SUSPENSION COMPRESSOR DRIER FAILURES

FORD:
1997-2002 EXPEDITION

LINCOLN:
1998-2002 NAVIGATOR

Article 03-7-9 is being republished in its entirety to update the Service Procedure.

ISSUE
Some 1997-2002 Expedition 4X4 and 1998-2002 Navigator 4X4 vehicles equipped with 4-wheel air suspension, may exhibit repeat air compressor drier failures. The drier cap may become detached from the drier body, or the drier body may be broken at the neck near the compressor head. This may be due to incomplete or incorrect system diagnosis that leads to replacement of only the original air suspension compressor, despite the fact that the compressor is not the root cause of the concern. Compressor failure in these instances is only a symptom of an underlying system problem.

ACTION
Refer to the service information contained in this TSB for information on proper diagnosis of system issues. Be sure to check the system for proper pneumatic function as described during service to ensure a robust repair.

SERVICE INFORMATION

Overview

Proper pneumatic function can be tested by verifying that both the front AND the rear of the vehicle can be raised and lowered one inch using a scan tool, and by monitoring the height sensor PIDs for movement while the vehicle is in the service bay. If the vehicle does not raise and lower normally, check the solenoid valves and air lines for blockages and/or restrictions. Replace any blocked or restricted solenoids and air lines. ALWAYS check for proper pneumatic function before returning the vehicle back to the customer.

NOTE DISCONNECTING AN AIR LINE THAT IS CONNECTED TO THE AIR COMPRESSOR CAN CAUSE PERSONAL INJURY OR DAMAGE TO COMPONENTS AS HIGH PRESSURE IS VENTED UNCONTROLLED.

If diagnostics lead to compressor/dryer assembly replacement, use the following service procedure to insure complete and thorough service.

1. Using the New Generation STAR (NGS) tester, vent the compressor/drier assembly.

2. Using regulated shop air, blow out the air lines from the drier to the front fill solenoid valve and from the drier to the rear fill solenoid valve, before installing the new compressor assembly.

3. Replace the air suspension compressor assembly. Refer to Workshop Manual Section 204-05 for compressor installation instructions.

4. Replace the front fill solenoid. Refer to Workshop Manual Section 204-05 for replacement instructions. The front fill solenoid must be replaced because in these cases, it may have sustained damage from the drier desiccant or other contaminants.

5. Connect the New Generation STAR (NGS) tester to the vehicle while the vehicle is parked in the service bay with the engine running.




 



6. Install a pressure gauge capable of reading 400 PSI at the front air line (Figure 1). Using the scan tool, command the compressor ON. Check the output of the compressor on the gauge:

a. If the compressor does not output at least 110 PSI within 30 seconds, replace the compressor again and retest.


NOTE VERIFY THAT THE SUSPENSION RAISES PROPERLY.

7. Using the scan tool, command the front of the vehicle to raise up one inch. The front suspension should rise one inch in 25 seconds or less.

a. If the compressor output is near 300 PSI, check4or air line or solenoid restrictions, repair as necessary and retest. Otherwise, proceed to Step 7b.


NOTE SUSPENSION UPWARD MOVEMENT CAN BE VERIFIED BY MONITORING EITHER OF THE FRONT HEIGHT SENSOR PIDS, WHICH SHOULD DECREASE BY .35 TO .45 VOLTS.

b. If the front of the vehicle DOES NOT raise, check the front pneumatic system for leaks, inoperable or blocked solenoid valves or pinched air lines. If an issue is found, repair as required and repeat Step 7 to verify proper operation.

c. If no problem found, continue to Step 8.

NOTE VERIFY THAT SUSPENSION PROPERLY.

8. If the front of the vehicle DOES raise, use the scan tool to command the front of the vehicle to lower one inch. The front suspension should lower one inch in 20 seconds or less.

NOTE SUSPENSION DOWNWARD MOVEMENT CAN BE VERIFIED BY MONITORING EITHER OF THE FRONT HEIGHT SENSOR PIDS, WHICH SHOULD INCREASE BY .35 TO .45 VOLTS.

a. If the front of the vehicle DOES NOT lower, check the front pneumatic system for leaks, inoperable or blocked solenoid valves, an inoperable vent solenoid, or pinched air lines. Repair air lines or replace solenoid valves as required.

9. Repeat Steps 7 and 8 for the rear. Command the rear of the vehicle, and monitor the rear height sensor PID. Voltages should increase when the vehicle is lowered, and decrease when the vehicle is raised. If the rear of the vehicle does not raise and lower as commanded, inspect the rear pneumatic system for leaks, inoperable or blocked solenoid valves, an inoperable vent solenoid, or pinched air lines, and repair as necessary.

10. If the vehicle raises and lowers normally in both the front and the rear, test drive the vehicle to confirm the repair.




 



Parts Block

OTHER APPLICABLE ARTICLES: NONE
SUPERSEDES: 03-7-9
WARRANTY STATUS: INFORMATION ONLY
OASIS CODES: 203000, 304000