300Tdi Discovery
STEERING
1
FAULT DIAGNOSIS
INSUFFICIENT POWER ASSISTANCE
1. Is fluid level correct?
YES - go to 3.
NO -
Fill/bleed sytem
2. Is problem a leak?
YES - Diagnose.
See Power Steering Fluid
Leaks
NO -
continue
3. Is drive belt tension correct?
YES - go to 5.
NO -
retension.
See ENGINE, Repair, Drive
Belt
4. Is problem resolved?
YES - end
NO -
continue
5. Carry out pressure test at idle and 1000 rev/min.
See Power Steering System - Test
6. Is correct pressure achieved?
YES - steering box defective
Not at any speed go to 9.
Not at idle go to 7.
7. Is idle speed correct?
YES - Go to 8.
NO -
Correct idle speed -
If 3.9
See ENGINE TUNING DATA,
Information, Engine 3.9 V8i
If Tdi
See ENGINE TUNING DATA,
Information, 300 Tdi Engine
If Mpi
See ENGINE TUNING DATA,
Information, Engine - Mpi - 2.0 Litre
8. Is problem resolved?
YES - end
NO -
go to 9.
9. Bypass steering box using adaptor tap
LRT-57-001
10. Is correct pressure obtained?
YES - defective steering box
NO -
defective steering pump
CAUTION: Do not hold steering wheel on
full lock for more than 30 seconds in any
one minute to avoid overheating fluid and
possibly damaging seals.
NOTE: 1. Excessive pressure in the
system is almost always caused by a
faulty relief valve in the PAS pump.
NOTE: 2. Insufficient pressure in the
system is usually caused by low fluid level
or PAS pump drive belt slip, or one of the
following: PAS system leaks, faulty PAS pump
relief valve, fault in steering box valve and worm
assembly, leak at piston in steering box, worn
components in PAS pump or box.