SAAB 9000. Manual — part 58

Fault Finding

REF•9

Transmission slips, shifts roughly, is noisy, or has no

drive in forward or reverse gears

 There are many probable causes for the above problems, but the

home mechanic should be concerned with only one possibility -

fluid level. Before taking the vehicle to a dealer or transmission
specialist, check the fluid level and condition of the fluid as
described in Chapter 1. Correct the fluid level as necessary, or
change the fluid and filter if needed. If the problem persists,
professional help will be necessary.

7 Driveshafts

Clicking or knocking noise on turns (at slow speed

on full-lock)

 Lack of constant velocity joint lubricant, possibly due to damaged

gaiter (Chapter 8).

 Worn outer constant velocity joint (Chapter 8).

8 Braking system

Vibration when accelerating or decelerating

 Worn inner constant velocity joint (Chapter 8).
 Bent or distorted driveshaft (Chapter 8).

Note: Before assuming that a brake problem exists, make sure that the
tyres are in good condition and correctly inflated, that the front wheel

alignment is correct, and that the vehicle is not loaded with weight in an
unequal manner. Apart from checking the condition of all pipe and hose
connections, any faults occurring on the anti-lock braking system
should be referred to a Saab dealer for diagnosis.

Vehicle pulls to one side under braking

 Worn, defective, damaged or contaminated front or rear brake pads

on one side (Chapters 1 and 9).

 Seized or partially-seized front or rear brake caliper piston (Chap-

ter 9).

 A mixture of brake pad lining materials fitted between sides

(Chapter 9).

 Brake caliper mounting bolts loose (Chapter 9).
 Worn or damaged steering or suspension components (Chapters 1

and

10).

Noise (grinding or high-pitched squeal) when brakes
applied

 Brake pad friction lining material worn down to metal backing

(Chapters 1 and 9).

 Excessive corrosion of brake disc - may be apparent after the

vehicle has been standing for some time (Chapters 1 and 9).

Brake pedal feels spongy when depressed

 Air in hydraulic system (Chapter 9).
 Deteriorated flexible rubber brake hoses (Chapters 1 and 9).
 Master cylinder mountings loose (Chapter 9).
 Faulty master cylinder (Chapter 9).

Excessive brake pedal travel

 Faulty master cylinder (Chapter 9).
 Air in hydraulic system (Chapter 9).
 Faulty vacuum servo unit (Chapter 9).

Excessive brake pedal effort required to stop vehicle

 Faulty vacuum servo unit (Chapter 9).
 Disconnected, damaged or insecure brake servo vacuum hose

(Chapters 1 and 9).

 Primary or secondary hydraulic circuit failure (Chapter 9).
 Seized brake caliper piston(s) (Chapter 9).
 Brake pads incorrectly fitted (Chapter 9).
 Incorrect grade of brake pads fitted (Chapter 9).
 Brake pads contaminated (Chapter 9).

Judder felt through brake pedal or steering wheel

when braking

 Excessive run-out or distortion of brake disc(s) (Chapter 9).
 Brake pad linings worn (Chapters 1 and 9).
 Brake caliper mounting bolts loose (Chapter 9).
 Wear in suspension or steering components or mountings

(Chapters 1 and 10).

Brakes binding

 Seized brake caliper piston(s) (Chapter 9).
Incorrectly-adjusted handbrake mechanism (Chapter 9).
 Faulty master cylinder (Chapter 9).

Rear wheels locking under normal braking

 Seized brake caliper piston(s) (Chapter 9).
D Faulty brake pressure regulator (Chapter 9).

9 Suspension and steering

Note: Before diagnosing suspension or steering faults, be sure that the
trouble is not due to incorrect tyre pressures, mixtures of tyre types, or
binding brakes.

Vehicle pulls to one side

 Defective tyre (Chapter 1).
 Excessive wear in suspension or steering components (Chapters 1

and

10).

 Incorrect front wheel alignment (Chapter 10).
 Accident damage to steering or suspension components (Chap-

ters 1 and 10).

Wheel wobble and vibration

 Front roadwheels out of balance (vibration felt mainly through the

steering wheel) (Chapter 10).

 Rear roadwheels out of balance (vibration felt throughout the

vehicle) (Chapter 10).

 Roadwheels damaged or distorted (Chapter 10).
 Faulty or damaged tyre (Chapter 1).
 Worn steering or suspension joints, bushes or components

(Chapters 1 and 10).

 Wheel bolts loose (Chapter 10).

REF•1O

Fault Finding

Excessive pitching and/or rolling around corners, or
during braking

 Defective shock absorbers (Chapters 1 and 10).
 Broken or weak coil spring and/or suspension component

(Chapters 1 and 10).

 Worn or damaged anti-roll bar or mountings (Chapter 10).

Wandering or general instability

 Incorrect front wheel alignment (Chapter 10).
 Worn steering or suspension joints, bushes or components

(Chapters 1 and 10).

 Road wheels out of balance (Chapter 10).
 Faulty or damaged tyre (Chapter 1).
 Wheel bolts loose (Chapter 10).
 Defective shock absorbers (Chapters 1 and 10).

Excessively-stiff steering

 Lack of steering gear lubricant (Chapter 10).
 Seized track rod end balljoint or suspension balljoint (Chapters 1

and

10).

 Broken or incorrectly adjusted auxiliary drivebelt (Chapter 1).

 Incorrect front wheel alignment (Chapter 10).
 Steering rack or column bent or damaged (Chapter 10).

Excessive play in steering

 Worn steering column universal joint(s) (Chapter 10).
 Worn steering track rod end balljoints (Chapters 1 and 10).
 Worn rack-and-pinion steering gear (Chapter 10).
 Worn steering or suspension joints, bushes or components

(Chapters 1 and 10).

10 Electrical system

Lack of power assistance

 Broken or incorrectly-adjusted auxiliary drivebelt (Chapter 1).
 Incorrect power steering fluid level (Chapter 1).
 Restriction in power steering fluid hoses (Chapter 1).
 Faulty power steering pump (Chapter 10).
 Faulty rack-and-pinion steering gear (Chapter 10).

Tyre wear excessive

Tyres worn on inside or outside edges

 Tyres under-inflated (wear on both edges) (Chapter 1).
 Incorrect camber or castor angles (wear on one edge only) (Chap-

ter

10).

 Worn steering or suspension joints, bushes or components

(Chapters 1 and 10).

 Excessively-hard cornering.
 Accident damage.

Tyre treads exhibit feathered edges

 Incorrect toe setting (Chapter 10).

Tyres worn in centre of tread

 Tyres over-inflated (Chapter 1).

Tyres worn on inside and outside edges

 Tyres under-inflated (Chapter 1).
 Worn shock absorbers (Chapters 1 and 10).

Tyres worn unevenly

 Tyres out of balance (Chapter 1).
 Excessive wheel or tyre run-out (Chapter 1).
 Worn shock absorbers (Chapters 1 and 10).
 Faulty tyre (Chapter 1).

Note: For problems associated with the starting system, refer to the
faults listed under "Engine" earlier in this Section.

Battery will not hold a charge for more than a few

days

 Battery defective internally (Chapter 5A).

 Battery electrolyte level low - where applicable (Chapter 1).
 Battery terminal connections loose or corroded (Chapter 1).
 Auxiliary drivebelt worn - or incorrectly adjusted, where applicable

(Chapter 1).

 Alternator not charging at correct output (Chapter 5A).
 Alternator or voltage regulator faulty (Chapter 5A).
 Short-circuit causing continual battery drain (Chapters 5A and 12).

Ignition/no-charge warning light remains illuminated

with engine running

 Auxiliary drivebelt broken, worn, or incorrectly adjusted (Chapter 1).
 Alternator brushes worn, sticking, or dirty (Chapter 5A).
 Alternator brush springs weak or broken (Chapter 5A).
 Internal fault in alternator or voltage regulator (Chapter 5A).
 Broken, disconnected, or loose wiring in charging circuit (Chap-

ter

5A).

Ignition/no-charge warning light fails to come on

 Warning light bulb blown (Chapter 12).
 Broken, disconnected, or loose wiring in warning light circuit

(Chapter 12).

 Alternator faulty (Chapter 5A).

Lights inoperative

 Bulb blown (Chapter 12).

 Corrosion of bulb or bulbholder contacts (Chapter 12).

 Blown fuse (Chapter 12).
 Faulty relay (Chapter 12).
 Broken, loose, or disconnected wiring (Chapter 12).
 Faulty switch (Chapter 12).

Instrument readings inaccurate or erratic

Instrument readings increase with engine speed

 Faulty voltage regulator (Chapter 12).

Fuel or temperature gauges give no reading

 Faulty gauge sender unit (Chapters 3 and 4).
 Wiring open-circuit (Chapter 12).
 Faulty gauge (Chapter 12).

Fuel or temperature gauges give continuous maximum

reading

 Faulty gauge sender unit (Chapters 3 and 4).
 Wiring short-circuit (Chapter 12).
 Faulty gauge (Chapter 12).

Horn inoperative, or unsatisfactory in operation

Horn operates all the time

 Horn contacts permanently bridged or horn push stuck down

(Chapter 12).

Horn fails to operate

 Blown fuse (Chapter 12).
 Cable or cable connections loose, broken or disconnected (Chap-

ter

12).

 Faulty horn (Chapter 12).

Fault Finding

REF•11

Horn emits intermittent or unsatisfactory sound

 Cable connections loose (Chapter 12).
 Horn mountings loose (Chapter 12).
 Faulty horn (Chapter 12).

Windscreen /tailgate wipers inoperative, or

unsatisfactory in operation

Wipers fail to operate, or operate very slowly

 Wiper blades stuck to screen, or linkage seized or binding

(Chapters 1 and 12).

 Blown fuse (Chapter 12).
 Cable or cable connections loose, broken or disconnected (Chap-

ter

12).

 Faulty relay (Chapter 12).
 Faulty wiper motor (Chapter 12).

Wiper blades sweep over too large or too small an area of

the glass

 Wiper arms incorrectly positioned on spindles (Chapter 1).
 Excessive wear of wiper linkage (Chapter 12).
 Wiper motor or linkage mountings loose or insecure (Chapter 12).

Wiper blades fail to clean the glass effectively

 Wiper blade rubbers worn or perished (Chapter 1).

 Wiper arm tension springs broken, or arm pivots seized (Chap-

ter

12).

 Insufficient windscreen washer additive to adequately remove road

film (Chapter 1).

Windscreen /tailgate washers inoperative, or

unsatisfactory in operation

One or more washer jets inoperative

 Blocked washer jet (Chapter 1).

 Disconnected, kinked or restricted fluid hose (Chapter 12).
 Insufficient fluid in washer reservoir (Chapter 1).

Washer pump fails to operate

 Broken or disconnected wiring or connections (Chapter 12).
 Blown fuse (Chapter 12).
 Faulty washer switch (Chapter 12).
 Faulty washer pump (Chapter 12).

Washer pump runs for some time before fluid is emitted

from jets

 Faulty one-way valve in fluid supply hose (Chapter 12).

Electric windows inoperative, or unsatisfactory in

operation

Window glass will only move in one direction

 Faulty switch (Chapter 12).

Window glass slow to move

 Regulator seized or damaged, or in need of lubrication (Chapter 11).
 Door internal components or trim fouling regulator (Chapter 11).
 Faulty motor (Chapter 11).

Window glass fails to move

 Blown fuse (Chapter 12).
 Faulty relay (Chapter 12).
 Broken or disconnected wiring or connections (Chapter 12).
 Faulty motor (Chapter 11).

Central locking system inoperative, or unsatisfactory

in operation

Complete system failure

 Blown fuse (Chapter 12).
 Faulty relay (Chapter 12).
 Broken or disconnected wiring or connections (Chapter 12).

REF•12

Glossary of Technical Terms

ABS (Anti-lock brake system) A system,
usually electronically controlled, that senses
incipient wheel lockup during braking and
relieves hydraulic pressure at wheels that are
about to skid.
Air bag An inflatable bag hidden in the
steering wheel (driver's side) or the dash or
glovebox (passenger side). In a head-on
collision, the bags inflate, preventing the driver
and front passenger from being thrown
forward into the steering wheel or windscreen.
Air cleaner A metal or plastic housing,
containing a filter element, which removes
dust and dirt from the air being drawn into the
engine.

Air filter element The actual filter in an air
cleaner system, usually manufactured from

pleated paper and requiring renewal at regular
intervals.

Air filter

Allen key A hexagonal wrench which fits into
a recessed hexagonal hole.
Alligator clip A long-nosed spring-loaded
metal clip with meshing teeth. Used to make
temporary electrical connections.
Alternator A component in the electrical
system which converts mechanical energy
from a drivebelt into electrical energy to
charge the battery and to operate the starting
system, ignition system and electrical
accessories.

Ampere (amp) A unit of measurement for the
flow of electric current. One amp is the
amount of current produced by one volt
acting through a resistance of one ohm.
Anaerobic sealer A substance used to

prevent bolts and screws from loosening.

Anaerobic means that it does not require
oxygen for activation. The Loctite brand is
widely used.
Antifreeze A substance (usually ethylene
glycol) mixed with water, and added to a
vehicle's cooling system, to prevent freezing
of the coolant in winter. Antifreeze also
contains chemicals to inhibit corrosion and
the formation of rust and other deposits that
would tend to clog the radiator and coolant

passages and reduce cooling efficiency.

Anti-seize compound A coating that

reduces the risk of seizing on fasteners that
are subjected to high temperatures, such as
exhaust manifold bolts and nuts.

Asbestos A natural fibrous mineral with great
heat resistance, commonly used in the
composition of brake friction materials.

Asbestos is a health hazard and the dust
created by brake systems should never be

inhaled or ingested.

Axle A shaft on which a wheel revolves, or
which revolves with a wheel. Also, a solid
beam that connects the two wheels at one
end of the vehicle. An axle which also
transmits power to the wheels is known as a

live axle.

Axleshaft A single rotating shaft, on either
side of the differential, which delivers power
from the final drive assembly to the drive
wheels. Also called a driveshaft or a halfshaft.

B

Ball bearing An anti-friction bearing
consisting of a hardened inner and outer race
with hardened steel balls between two races.
Bearing The curved surface on a shaft or in a
bore, or the part assembled into either, that
permits relative motion between them with
minimum wear and friction.

Bearing

Big-end bearing The bearing in the end of

the connecting rod that's attached to the
crankshaft.
Bleed nipple A valve on a brake wheel
cylinder, caliper or other hydraulic component
that is opened to purge the hydraulic system
of air. Also called a bleed screw.
Brake bleeding Procedure for removing air
from lines of a hydraulic brake system.

Brake drum The component of a drum brake

that rotates with the wheels.

Brake linings The friction material which
contacts the brake disc or drum to retard the

vehicle's speed. The linings are bonded or
riveted to the brake pads or shoes.
Brake pads The replaceable friction pads
that pinch the brake disc when the brakes are
applied. Brake pads cofisist of a friction
material bonded or riveted to a rigid backing
plate.
Brake shoe The crescent-shaped carrier to
which the brake linings are mounted and
which forces the lining against the rotating
drum during braking.
Braking systems For more information on
braking systems, consult the Haynes

Automotive Brake Manual.

Breaker bar A long socket wrench handle
providing greater leverage.
Bulkhead The insulated partition between

the engine and the passenger compartment.

Caliper The non-rotating part of a disc-brake
assembly that straddles the disc and carries
the brake pads. The caliper also contains the
hydraulic components that cause the pads to
pinch the disc when the brakes are applied. A
caliper is also a measuring tool that can be
set to measure inside or outside dimensions
of an object.
Camshaft A rotating shaft on which a series
of cam lobes operate the valve mechanisms.

The camshaft may be driven by gears, by
sprockets and chain or by sprockets and a

belt.
Canister A container in an evaporative

emission control system; contains activated
charcoal granules to trap vapours from the
fuel system.

Brake bleeding

Brake disc The component of a disc brake

that rotates with the wheels.

Canister

Carburettor A device which mixes fuel with
air in the proper proportions to provide a
desired power output from a spark ignition
internal combustion engine.
Castellated Resembling the parapets along
the top of a castle wall. For example, a
castellated balljoint stud nut.
Castor In wheel alignment, the backward or

forward tilt of the steering axis. Castor is

positive when the steering axis is inclined
rearward at the top.

c

A