Mike reports that silver soldering should hold more than 200 Bar (3000 psi) of pressure (he uses this method for some diving equipment changes). However he is sure that brazing them on will hold the 10 Bar (150 psi) max of the RR air system. The one change Mike still wants to make is a plate bolted on the rear of the compressor box whereby all four valves can be mounted in their corresponding position. This would make it easy to pump them up from one area and not guess which is which. It would also help if you just wanted to push a tyre pump against them without them moving around.
Mike is also looking into a scheme for hooking into the wiring system to control the valves and pump separately through a little box that can be kept under the seat and pulled out when needed. This will make the getting out of the vehicle in the rain, etc., a little less hassle when you want to overide the system. For a cruder version of this type of solution, see the section below on using jumpers to operate the EAS solenoid valves.
Another approach to modifying the air lines to allow manual pumping up of the system was contributed by Justin Tiemeyer; for details see the EAS Replumbing page.
2. Commercial Air Valve Conversion Kits
Commercial kits are now available to achieve the same effect as the home-made tire valve system described above. One such system is the Black Dog Air Valve Conversion Kit available from MotorcarsLtd. The kit includes standard air fittings that allow you to plug a regular tire pump in to the air line for any spring and pump it up to the desired height.
A less expensive alternative is available from Airbag Man, an Australian manufacturer who ship worldwide. Their Range Rover Safety/Emergency "E" Kit (part number DRK001) enables each air spring to be inflated remotely and independently. The system locks out the air supply from the valve block and allows you to add air from any source such as a service station pump or another vehicle with an onboard air supply. You can also isolate a leaking spring so it won't cause all the others to deflate. The kit comes complete with 4 lockout valves, 4 remote inflation valves, tubing, tube cutter and full instructions.
More recently, an even lower cost kit is available from Justin Tiemeyer at CarrollRovers -- for full information on this system see the page on Replumbing the Air Suspension for Manual Pump-up.
3. Manual Activation of EAS Valves using Jumper Wires
If your EAS system has gone into hard fault mode, but
there are no leaks (eg you have replaced a leaking air bladder) and
nothing is wrong with the compressor or the valve block, you can
restore normal ride height through crafty use of jumper wires to
operate the solenoid valves in the valve block manually, causing air to
flow in the appropriate directions. If the air supply is exhausted, you
may first have to manually operate the compressor (see section 4 below)
to fill up the reservoir.
I would suggest removing the EAS timer/delay module first (see
picture at this link) to
prevent the dash lighting up like a Christmas tree. You can then unplug
the connector (designated C117 on the 4.0/4.6 and C331 on Classic EAS
models) to the EAS ECU under the left hand
passenger seat (see photo art right, 4.0/4.6). Partially disassembling
the
connector by unscrewing the single screw on its shell and sliding the
cover off allows you to get access to the back of the pins and read the
numbers. Alternatively, on the 4.0/4.6 you can accomplish the same
result using connector
C152 inside the plastic EAS enclosure for the compressor and valve
block in the engine bay. (Connector C139 underneath the valve
block would be even better, as it is the least
ambiguous in the circuit diagram provided in the ETM, but unfortunately
it is inaccessible without removing the entire valve block -- see valve block removal procedure).
 |
 |
 |
| EAS Timer
Relay located under left side of LH front seat (4.0/4.6) |
ECU
Connector C117 located under front of LH front seat on 4.0/4.6 (C331 on
Classic) |
Location of Connector C152
(4.0/4.6) |
Following the circuit diagram in the Electrical Troubleshooting
Manual, you can then jumper the necessary wires to raise or lower any
corner of the vehicle. Note that you have to activate two valves for
any action; as well as activating the solenoid valve for the particular
air bladder of interest, you must activate the "inlet" valve to pump it
up or the "exhaust" valve to let air out. The following table lists the
connections that you need to jumper to
+12 to operate the various valves.
| Connector
C117 (4.0/4.6) Connector C331 (Classic) Under seat (Jumper these pins to +12 or pin 1) |
Connector
C152 (4.0/4.6) Top front of valve block (Jumper these pins to +12 or pin 7, 12 or13 ) |
Connector
C139 (4.0/4.6) Underneath valve block (Jumper these pins to +12) |
|
| Left Rear |
11 |
1 |
2 |
| Right Rear |
28 |
2 |
13 |
| Left Front |
10 |
3 |
6 |
| Right Front |
27 |
4 |
1 |
| Inlet |
26 |
5 |
7 |
| Exhaust |
9 |
6 |
4 |
Mark Chandler used this method under
fault conditions on his Classic LWB -- this link lists
the exact jumper connections he
used. Mark
Hudson recently reported
that he used the method successfully on his 4.0/4.6 when it
went into hard fault mode. He used a further refinement of adding a
lead to the hot wire on his battery anytime he wanted the system
to leap into action. Walter Burton suggested making a wire "X" to make
it easier to connect
up to four contacts together. He took two wires four inches long with
1/4 inch insulation removed from each end. He removed 1 inch insulation
in the center of each, then twisted the centers
together to make 4 pigtails all connected at the center. Tim Sims reports using the
above information to great effect getting a Classic up off the bump
stops after a hard fault was generated during an operation to change
the shocks. Curtis Keller found
that 16 gauge wire worked best for him as jumpers -- 24 gauge wire was
too thin to make reliable contact in the connectors. Andy Cunningham suggests
finding a junked EAS ECU and using the connector from it to wire in
sutable switches for emergency operation of the valves and/or
compressor (below).
4. Manual Activation of Air Compressor
If you are in hard fault mode, and want to restore system air pressure (eg in preparation for manual override of the solenoid valves as outlined above, or in preparation for restoring normal EAS operation), you can get the compressor to operate using jumper wires. I found the easiest way to do this is to lift the lid off the engine compartment fuse box, pull out Relay 20 which supplies current to the compressor. You can then easily jumper its output terminal (pin 5) to +12 volts and the compressor will start running. I found an easy way to do this is to poke a small screwdriver into the empty relay socket (pin 5) and connect a jumper lead from the screwdriver to the exposed terminal of any adjacent maxi-fuse.
Another method of getting the compressor to operate if you are in fault mode is to jumper pins 1 and 8 of the EAS ECU connecctor C117 under the left front seat (see photo at right courtesy of Ron Beckett, and detailed description of this method under "Restoring Normal Operation" on the EAS Field Recovery Page).
Andy Cunningham suggests finding a junked EAS ECU and using the connector from it to wire in sutable switches for emergency operation of the valves and/or compressor.
Caution: These methods bypass the overpressure switch, so you will need to be careful not to overpressurize the system. (To avoid this, Chris McAuliffe suggests you can monitor pin 13 for 12 volts. When the voltage comes up you've reached the point where the ECU would turn the compressor off). Similarly, the compressor's thermal cutout switch is bypassed, so be careful not to run the compressor for extended periods and overheat it.
(For additional information on compressor problems and solutions see the Compressor Diagnosis and Replacement Page).
5. Pumping up the EAS System with an External Compressor
When Mark Hudson's compressor needed replacing (but before the system went into hard fault mode), he successfully operated the EAS system by pumping it up witrh an external emergency compressor. He reports "Before I replaced the compressor I was able to air up the suspension using my compressor at home. I simply disconnected the air hose from the compressor, slipped a plastic tube over it and clamped it the best I could. Air leaked out like crazy, but I was able to air up the bags and they stayed up due to the back-flow preventer valve".
6. Inserting an Aftermarket Control System
If you tire of the OEM system, Dakota Digital makes a complete air suspension control system for $795 including a remote control option. It does all the automatic ride height functions, as well as lets you control each bag individually. It also comes with a nice display to let you know what's going on. If anyone tries this, please email me so we can share your experiences with other owners.
More Information
Air Suspension Replumbing for Manual Pump-up
Air Suspension Diagnosis and Field Repair
Air Spring Replacement
Air Spring Replacement (Bladder Only) (Classic, 4.0/4.6)
Air Suspension Valve Block Repairs
Air Suspension Disabling (4.0/4.6)
Arnott Generation III Air Spring Upgrade: firmer on hwy, softer off road and more travel
EAS Compressor Diagnosis and Replacement
Range Rover Suspension Info
Extended Profile Selector (4.0/4.6)
Lifting the Air Suspension
Replacing with Coil Springs (Classic, 4.0/4.6)
Replumbing the system for Manual Pump-up
Tapping into the Air Supply for Tire Inflation etc
Valve Block Problems and Solutions