low oil pressure LAND ROVER DEFENDER 1999 Owner's Guide

FRONT AXLE AND FINAL DRIVE
1
FAULT DIAGNOSIS FAULT DIAGNOSIS
Complaint - Oil leaks
An external leak of lubrication can be caused by a
faulty internal seal. For example, if the seals which
separate the differential from the swivel housings are
faulty and the vehicle is operating or parked on an
embankment, oil may leak across the axle leaving one
swivel with a high level and the opposite swivel and
differential lacking lubrication.
See’Description and Operation’for illustrations of oil
seal locations.
When investigating leaks or checking oil levels, it is
essential that all the lubrication is drained from any
housing with a high level and that the other levels are
checked.
Swivel oil should be checked for signs of grease
leaking from the hub bearings and oil contamination of
the hub grease.
Check that the axle ventilation system is clear, as a
blockage can cause internal pressure to force oil past
the seals.
If the vehicle is driven in deep water with defective oil
seals, water may contaminate the lubricants and when
checked, give a false impression that the housing has
been over filled with oil.
Do not assume that a high oil level is due to over
filling or, that a low level is because of an external
leak.
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AIR CONDITIONING
1
ADJUSTMENT REFRIGERANT RECOVERY, RECYCLING,
RECHARGING
Service repair no - 82.30.02
WARNING: The air conditioning system is
charged with a high pressure, potentially
toxic refrigerant. Repairs or servicing must
only be carried out by an operator familiar with
both the vehicle system and the charging and
testing equipment.
WARNING: All operations must be carried
out in a well ventillated area away from
open flame and heat sources.
WARNING: Wear eye and hand safety
protection.
CAUTION: Overcharging air conditioning
system will cause excessive head
pressure.
An air conditioning portable Refrigerant Recovery
Recycling Recharging Station for use with R134a
refrigerant incorporates all the features necessary to
recover R134a refrigerant from the air conditioning
system; to filter and remove moisture; to evacuate and
recharge with the reclaimed refrigerant. The unit can
also be used for performance testing and air
conditioning system analysis.
The operator must adhere to the equipment
manufacturer’s instructions.
Refrigerant Recovery
1.Remove dust caps from high and low pressure
connectors.
2.Connect high and low pressure hoses to
appropriate connections.
3.Open valves on connectors.
4.Turn valves on refrigerant station to correct
positions.
NOTE: Operate the refrigerant station in
accordance with the manufacturers
instructions.
5.Turn Process switch to correct position.
6.Turn Main switch to’ON’.
7.Allow station to recover refrigerant from system.8.Close valves on refrigerant station.
9.Turn Main switch to’OFF’.
10.Close valves on connectors.
11.Disconnect high and low pressure hoses from
connectors.
12.Fit dust caps to connectors.
13.Open tap at rear of station to drain refrigerant oil
recovered from system.
14.Measure and record quantity of refrigerant oil
recovered from system.
15.Close tap at rear of station.
Evacuation
CAUTION: Whenever the refrigerant
system is opened, the receiver/drier must
be renewed immediately before evacuating
and recharging the system.
1.Remove dust caps from high and low pressure
connectors.
2.Connect high and low pressure hoses to
appropriate connections.
3.Open valves on connectors.
4.Turn valves on refrigerant station to correct
positions.
5.Turn Process switch to correct position.
6.Turn Main switch to’ON’.
7.Allow station to evacuate system.
NOTE: If the vacuum reading is below
700mmHg after 15 minutes, suspect a leak
in the system. Partially recharge the
system and check for leaks using an electronic
leak tester. Check suction lines first, then run the
compressor for 5 minutes. Next check the high
pressure lines.
NOTE: The system must be evacuated
immediately before recharging
commences. Delay between evacuation
and recharging is not permitted.
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82AIR CONDITIONING
2
ADJUSTMENT Recharging
WARNING: Refrigerant must always be
recycled before re-use, to ensure that the
purity of the refrigerant is high enough for
safe use within the air conditioning system.
Recycling should always be carried out with
equipment which is design certified by
Underwriter Laboratory Inc. for compliance with
SAE-J1991. Other equipment may not re-cycle the
refrigerant to the required level of purity.
WARNING: A R134a Refrigerant Recovery
Recycling Recharging station must not be
used with any other type of refrigerant.
WARNING: R134a refrigerant from
domestic and commercial sources must
not be used in motor vehicle air
conditioning systems.
CAUTION: When a major repair has been
carried out, a leak test should be carried
out using inert gas.
1.Close valves on refrigerant station.
2.Close valve on oil charger.
3.Disconnect yellow hose from refrigerant station.
4.Remove lid from oil charger.
5.Pour correct quantity of refrigerant oil into oil
charger.
6.Fit lid to oil charger.
7.Connect yellow hose to refrigerant station.
8.Open valve on oil charger.
9.Move pointer on refrigerant gauge to mark
position of refrigerant drop.
10.Slowly open correct valve on refrigerant station
and allow vacuum to pull refrigerant into system.
11.Close valve on refrigerant station when correct
amount of refrigerant has been drawn into air
conditioning system.
12.If the full charge is not accepted by the system,
start the engine and run it at 1,500 rev/min for a
minimum of 2 minutes. Switch on the air
conditioning system, open the vehicle windows,
set the temperature control to cold and the
blower switch to maximum.
13.Consult Refrigerant station instruction manual for
correct procedure to complete the charge.
14.Turn Main switch to’OFF’.
15.Close valves on connectors.
16.Disconnect high and low pressure hoses from
connectors.
17.Fit dust caps to connectors.
18.Carry out performance test on air conditioning
system.
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ELECTRICAL
21
DESCRIPTION AND OPERATION The Heated Front Screen (HFS) is a new feature for 2002MY which is available as part of a cold climate pack on
Td5 engine variants only. The HFS system comprises an HFS ECU, an HFS relay, a controlling switch and the
HFS elements.
The HFS comprises two elements laminated in the windscreen. The elements are connected by bus bars within
the screen and therefore the HFS has only one feed and one earth connector.
The HFS is controlled by the HFS ECU which determines when HFS operation is permitted. The ECU also has a
timer which allows HFS operation for up to 8 minutes. The HFS ECU is located behind the instrument pack,
adjacent to the dim/dip relay. The ECU is connected by a multiplug. The ECU receives an ignition feed via the
satellite fuse box and an engine running signal from the engine oil pressure switch.
A non-latching switch for HFS operation is located in the fascia. The switch has a tell-tale lamp to indicate when
the HFS screen is operative.
The HFS relay is located in the under seat fuse box and receives a permanent battery voltage supply via fusible
link 1 in the under seat fuse box. The relay coil is connected to the HFS ECU and an earth point. When the relay is
operated, battery voltage is supplied from the relay, via fuse 25 in the passenger compartment fuse box to the
HFS element.
When the HFS switch is depressed, a momentary earth path is completed from the HFS ECU, through the switch
to earth. This is sensed by the ECU as a request for HFS operation. If the ECU receives an ignition on signal and
an oil pressure signal, it allows HFS operation. The ECU provides an output to the coil of the HFS relay. When the
coil is energised, the contacts close and battery voltage, via fusible link 1 in the under seat fuse box is supplied to
the HFS element, via fuse 25 in the passenger compartment fuse box. The feed is also supplied via a splice joint
to the HFS switch to illuminate the tell tale lamp in the switch.
The HFS ECU will allow screen operation for up to 8 minutes, after which it removes the feed to the HFS relay
coil, which, after the contacts open, removes the supply to the HFS element and simultaneously extinguishing the
tell tale lamp in the switch. If, during the timed operation period, the HFS ECU receives an additional request
signal from operation of the switch, HFS operation is stopped.
When operating, the HFS element draws approximately 25 Amps. To prevent excess drain on the vehicle battery,
if the ignition on signal and/or the oil pressure switch (engine running) signal is lost, the HFS ECU de-energises, if
already operating, or will not energise the HFS relay.
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