1988 OPEL CALIBRA high beam

Wiring diagrams 12•25
12
Key to wiring diagrams for 1989 models (continued)
S21Front foglamp switch450 to 452
S22Rear foglamp switch455 to 457
S27Air conditioning compressor low-pressure switch (not UK)821
S28Air conditioning compressor high-pressure switch (not UK)821
S29Cooling fan switch113
S30Seat heater switch - front left575 to 577
S31Rear door courtesy lamp switch - left491
S32Rear door courtesy lamp switch - right492
S35Sunroof travel microswitch692
S36Sunroof travel microswitch694
S37Electric windows switch assembly637 to 663
S37.1Electric window switch - front left637 to 639
S37.2Electric window switch - front right655 to 657
S37.3Electric window switch - rear left643 to 645
S37.4Electric window switch - rear right661 to 663
S37.5Electric windows safety cut-out switch641 to 642
S37.6Electric windows anti-jam switch659
S37.7Electric windows automatic control646 to 651
S39Electric windows switch - rear left door647 to 649
S40Electric windows switch - rear right door665 to 667
S41Central locking switch driver’sdoor601 to 603
S42Central locking switch passenger door605
S44Throttle position sensor173 to 174, 278 to 279
S47Driver’s door courtesy lamp switch493 to 494
S51Cooling fan switch (not UK models)825 to 827
S52Hazard warning flasher switch469 to 474
S55Seat heater switch - front right579 to 581
S57Sunroof switch690 to 696
S63.1Trip computer function reset switch543
S63.2Trip computer clock hours adjustment switch544
S63.3Trip computer function select switch545
S63.5Trip computer clock minutes adjustment switch546
S64Horn switch591 to 594
S68.1Door mirror adjustment switch672 to 677
S68.2Door mirror heater switch679 to 680
S68.3Door mirror left/right selector switch673 to 677
S76Air conditioning compressor switch -high-pressure,
cooling fan (not UK)832
S82Washer pump switch371
S91Oil pressure switch (not UK models)165 to 166
S93Coolant level sensor372
S95Oil level sensor373
S98Headlamp aim adjustment switch556 to 558
S99Electric windows switch - driver’s door634
S100Electric windows switch -passenger door652
S104Kickdown switch (automatics)792
S105Start-up assistance switch (automatics)796 to 798
S106Economy/power programme switch (automatics)791
S107Throttle position sensor 771 to 776
S108Cooling fan switch (Diesel models)847 to 848
S109Air conditioning compressor switch (not UK)817
S110Ride control switch (not UK)738 to 743S115Automatic transmission fluid temperature sensor793
S116Brake lamp switch464 to 465
S117Four-wheel-drive hydraulic pressure switch729
S118Air conditioning refrigerant temperature switch (not UK)829
U2Trip computer538 to 548
U4ABS hydraulic modulator assembly705 to 718
U4.1ABS hydraulic pump relay706 to 709
U4.2ABS solenoid valves relay715 to 718
U4.3ABS hydraulic pump705
U4.4ABS diode717
U4.5ABS solenoid valve - front left710
U4.6ABS solenoid valve - front right711
U4.7ABS solenoid valve - rear left712
U4.8ABS solenoid valve - rear right713
U5.1Check control tail lamp and dipped beam bulb failure
warning lamp362
U5.2Check control brake lamp bulb failure warning lamp 363
U5.3Check control coolant oil level warning lamp360
U5.5Check control brake pad wear warning lamp364
U5.6Check control washer fluid level warning lamp359
U5.7Check control coolant level warning lamp361
U7Air conditioning control unit (not UK)806 to 824
U7.6Air conditioning blower switch (not UK)806 to 811
U7.8Air conditioning switch (not UK)813 to 824
U12.1Temperature switch (Diesel models)865
U12.2Fuel filter heater (Diesel models)866
U13.1Automatic transmission solenoid valve -shift 1784
U13.2Automatic transmission solenoid valve - shift 2785
U13.3Automatic transmission solenoid valve - lock-up control786
U13.4Automatic transmission solenoid valve - pressure control787
V1Brake fluid level warning lamp test diode (not UK)312
V8 Air conditioning compressor diode (not UK)820
X1Trailer electrical socket453 ,458 to 460
X2Accessory electrical connectors587
X5 toWiring connectorsVarious
X62
Y1Air conditioning compressor clutch (not UK)821
Y4Headlamp washer solenoid valve523
Y5Fuel solenoid valve (Diesel models)860
Y7Fuel injectors186 to 193, 280 to 287
Y10Distributor (Hall-effect)249 to 253
Y23Distributor (Inductive discharge)123 to 127
Y24Distributor (Inductive discharge) (not UK)129 to 136
Y26Throttle valve positioner (not UK)201 to 207
Y27Pre-throttle valve (not UK)218 to 219
Y30Cold start valve (Diesel models)863
Y32Fuel injector (not UK)140
Y33Distributor170, 262
Y34Fuel tank ventilation valve (not UK)198, 292
Y43Air conditioning vacuum control (not UK)815 to 818
Y44Four-wheel-drive solenoid valve731 NoDescriptionTrackNoDescriptionTrack

12•40Wiring diagrams
Key to wiring diagrams for 1991 models (continued)
NoDescriptionTrackNoDescriptionTrack
S1.2Key contact switch586
S2.1Lighting switch404 to 407
S2.2Courtesy lamp switch487
S2.3Instrument illumination lamp dimmer328
S3Heater blower switch853 to 860
S4Heated rear window and mirror switch554 to 556
S5.2Dipped beam switch438 to 439
S5.3Direction indicator switch480 to 482
S5.4Sidelamp switch401 to 402
S7Reversing lamp switch497
S8Brake lamp switch462
S9.2Windscreen wiper interval switch501 to 504
S9.5Rear window washer/wiper switch514 to 516
S10Automatic transmission starter inhibitor switch773 to 779
S11Brake fluid level warning sensor31
S13Handbrake-on warning switch315
S14Oil pressure switch310
S15Luggage compartment lamp switch485
S17Passenger door courtesy lamp switch490
S21Front fog lamp switch450 to 452
S22Rear foglamp switch455 to 457
S24Air conditioning blower motor switch804 to 811
S27Air conditioning compressor low-pressure switch821
S28Air conditioning compressor high-pressure switch821
S29Cooling fan switch113
S30Driver’s seat heater switch560 to 562
S31Rear door courtesy lamp switch - left491
S32Rear door courtesy lamp switch - right491
S37Driver’s door electric window switch assembly668 to 694
S37.1Electric window switch - front left668 to 670
S37.2Electric window switch - front right686 to 688
S37.3Electric window switch - rear left674 to 676
S37.4Electric window switch - rear right692 to 694
S37.5Electric window safety cut-out switch672 to 673
S37.6Electric window anti-jam switch690
S37.7Electric window automatic control677 to 682
S39Electric window switch - rear left door678 to 680
S40Electric window switch - rear right door696 to 698
S41Central locking switch - driver’s door601 to 603
S42Central locking switch - passenger door605
S44Throttle position sensor278 to 279
S47Driver’s door courtesy lamp switch493 to 494
S52Hazard warning flasher switch469 to 474
S55Passenger seat heater switch564 to 566
S57Sunroof switch864 to 869, 872 to 877
S63.1Trip computer function reset switch656
S63.2Trip computer clock hours adjustment switch657
S63.3Trip computer function select switch658
S63.5Trip computer clock minutes adjustment switch659
S64Horn switch592, 595
S68.1Door mirror adjustment switch538 to 540, 945 to 950
S68.3Door mirror left/right selector switch537 to 541, 946 to 950
S68.4Door mirror parking position switch952
S76Air conditioning compressor switch - high-pressure fan827
S82Washer pump switch347, 392
S88Cooling fan switch115 to 116, 935 to 936
S93Coolant level sensor348, 393
S95Oil level sensor349, 394
S98Headlamp aim adjustment switch758 to 760
S99Electric window switch - driver’s door685
S100Electric window switch - passenger door683
S101Air conditioning compressor switch822 to 824
S102Air conditioning circulation switch816 to 818
S104Automatic transmission kickdown switch794
S105Automatic transmission “Winter” mode button796 to 798
S106Automatic transmission “Economy/Sport” mode button793S109Air conditioning compressor switch818
S115Automatic transmission coolant temperature switch788 to 789
S116Brake lamp switch464 to 465
S117Four-wheel-drive hydraulic pressure switch729
S119Air conditioning refrigerant temperature switch829, 843
S120Anti-theft alarm bonnet switch635
S127Central locking switch - tailgate (Calibra models)630
S128Air conditioning refrigerant temperature cooling switch825 to 826
S131Air conditioning defroster lever limit switch815
U2Trip computer651 to 662
U4ABS hydraulic modulator assembly705 to 718, 738 to 751
U4.1ABS hydraulic pump relay706 to 709, 739 to 742
U4.2ABS solenoid valves relay715 to 718, 747 to 751
U4.3ABS hydraulic pump705, 738
U4.4ABS diode717
U4.5ABS solenoid valve - front left710, 743
U4.6ABS solenoid valve - front right711, 744
U4.7ABS solenoid valve - rear left712, 745
U4.8ABS solenoid valve - rear right713
U5Check control display347 to 355
U5.1Check control washer fluid level warning lamp352
U5.2Check control oil level warning lamp351
U5.3Check control coolant level warning lamp350
U5.4Check control tail lamp and dipped beam bulb
failure warning lamp349
U5.5Check control brake lamp bulb failure warning lamp348
U5.6Check control brake wear warning lamp347
U6LCD instruments
U6.1Check control washer fluid level warning lamp392
U6.2Check control oil level warning lamp394
U6.3Check control coolant level warning lamp393
U6.4Check control tail lamp and dipped beam bulb
failure warning lamp391
U6.5Check control brake lamp bulb failure warning lamp395
U6.6Check control brake pad wear warning lamp396
U12.1Temperature switch (Diesel models)898, 931
U12.2Fuel filter heater (Diesel models)899, 932
U13AF14/20automatic transmission782 to 786
U13.1Solenoid - 1/2 and 3/4 shift up782
U13.2Solenoid - 2/3 shift up783
U13.3Solenoid - converter lock-up control784
U13.4Solenoid - main fluid pressure control785
V1Brake fluid level warning lamp test diode312
V8Air conditioning compressor diode820
Y1Air conditioning compressor clutch821
Y4Headlamp washer solenoid valve520
Y5Fuel solenoid valve (Diesel models)893, 928
Y7Fuel injectors187 to 194, 280 to 287
Y10Distributor (Hall-effect)246 to 251
Y23Distributor (inductive discharge)123 to 127
Y24Distributor (inductive discharge)129 to 136
Y25Idle-up solenoid valve (automatic transmission)242
Y30Cold start valve (Diesel models)896
Y32Fuel injector140, 979
Y33Distributor170, 262, 972 to 974
Y34Fuel tank vent valve193, 292
Y35Air conditioning circulation solenoid valve816
Y44Four-wheel-drive solenoid valve731
Y47Parking brake lock lifting magnet (automatic transmission)769
X13Diagnostic equipment connector149, 170 to 171, 254 to 255,
269 to 270, 325, 339 to 340,
752 to 753, 774 to 775, 992 to 993
X15Octane coding plug160, 184 to 185, 248 to 249, 990 to 991
X54Ignition coding plug270 to 271
X1 onWiring connectorsVarious

Wiring diagrams 12•55
12
Key to wiring diagrams for 1992 and later models
NoDescriptionTrackNoDescriptionTrack
E1Left parking lamp506
E2Left tail lamp507, 745
E3Licence plate lamp513
E4Right parking lamp509
E5Right tail lamp510, 746
E6Engine compartment lamp515
E7Left high beam 535
E8Right high beam536
E9Left low beam537, 747
E10Right low beam538, 748
E11Instrument lights728, 729
E12Selector lever lamp 498, 499
E13Boot lamp585
E14Passenger compartment lamp587
E15Glove box lamp677
E16Cigarette lighter lamp676
E17Left reversing lamp597
E18Right reversing lamp598
E19Heated back window652
E20Left fog lamp553
E21Right fog lamp554
E24Left rear fog lamp548
E25Left front heating mat660
E27Left rear reading lamp680, 681
E28Right rear reading lamp683, 684
E30Right front heating mat664
E32Clock lamp863
E37Left mirror make-up lamp686
E38Computer lamp854
E39Right rear foglamp549
E40Right mirror make-up lamp688
E41Passenger compartment delay lamp 588 to 590
E50Driver door lamp866
E51Passenger door lamp884
F1 onFusesVarious
F35Voltage stabilizer702
G1Battery101
G2Alternator114
G6Diesel alternator 402 to 405
H1Radio784 to 798
H3Turn signal lamp telltale716, 718
H4Oil pressure telltale710
H5Brake fluid telltale712
H6Telltale hazard warning system570
H7Charging indicator lamp710
H8High beam telltale722
H9Left stop lamp561, 749
H10Right stop lamp562, 750
H11Left front turn signal lamp572
H12Left rear turn signal lamp573
H13Right front turn signal lamp581
H14Right rear turn signal lamp582
H15Fuel telltale705, 706
H16Preheating time telltale715
H17Trailer turn signal lamp telltale717
H18Horn670
H19Headlamps on warning buzzer594, 595
H21Parking brake telltale713
H23Airbag telltale719
H25Heated back window & mirror telltale642, 765
H26ABS telltale721
H27Safety checking warning buzzer996 to 998
H28Seat belt warning telltale723
H30Engine telltale724H33Left auxiliary turn signal lamp576
H34Right auxiliary turn signal lamp578
H36Additional stop lamp563
H37Left front loudspeaker788 to 790
H38Right front loudspeaker794 to 796
H39Left rear loudspeaker788, 789
H40Right rear loudspeaker791, 792
H42Automatic program power telltale725
H45Four wheel drive telltale727
H46Catalytic converter temperature telltale729
H47Anti-theft warning unit horn838
H48Horn671
H51Traction control telltale720
H52Left front tweeter787 to 791
H53Right front tweeter793 to 797
K3Starter relay anti-theft warning unit109, 110
K5Fog lamps relay554 to 555
K6Air conditioning relay901, 902
K7Four stage air conditioning blower relay904, 905
K8Windshield wiper interval relay603 to 606
K9Headlamps washer unit relay619, 620
K10Flasher unit567 to 569
K20Ignition coil module149, 150, 171, 172, 241, 242, 302 to 305,
361 to 364, 1001 to 1005, 1055 to 1061
K22Coolant pump relay133, 134, 969, 970
K25Glow time relay440 to 443
K26Radiator blower relays972 to 974
K27Radiator blower relay137 to 139
K30Back window wiper interval relay613 to 615
K31Airbag control unit1191 to 1198
K34Radiator blower time delay relay356 to 358, 956 to 958
K35Heated back window & mirror time delay relay650 to 652
K37Central locking control unit805 to 812
K51Radiator blower relay430, 431, 942, 943, 956, 957
K52Radiator blower relay145 to 147, 433,435,
982 to 984, 960 to 962
K57Multec unit control211 to 230, 244 to 262
K58Fuel pump relay231, 232, 262, 263
K59Running light relay520 to 525
K60Compressor relay931,932
K61Motronic control unit270 to 294, 307 to 337,
366 to 396, 1007 to 1037, 1063 to 1096
K63Horn relay671, 672
K641 stage air conditioning blower relay913, 914
K67Radiator blower relay142, 143, 436, 437, 948,
949, 964, 965, 986, 987
K68Fuel injection unit relay295 to 299, 393 to 397,
334 to 338, 1093 to 1097, 1034 to 1038
K73High beam relay (Calibra)530, 531
K76Glow time control unit413 to 417
K77Glow plugs relay419, 420
K78Preresistor relay (70A)422, 423
K79Charge indicator relay406 to 408
K80Filter heating relay426, 427, 452, 453
K82Engine revolution relay447, 448
K83Four wheel drive unit control342 to 349
K84EZ Plus control unit155 to 166, 177 to 191
K85Automatic transmission control unit473 to 496
K86Check control unit736 to 752
K87Radiator blower relay945, 946, 953, 954, 977, 978
K88Catalytic converter temperature control unit462 to 464
K89Rear fog lamp relay543 to 545
K90Compressor relay (automatic transmission only)930, 931
K94Anti-theft warning unit control unit833 to 847

Wiring diagrams 12•57
12
Key to wiring diagrams for 1992 and later models (continued)
NoDescriptionTrackNoDescriptionTrack
S20.2High pressure compressor switch925
S20.3High pressure blower compressor switch939
S21Fog lamps switch555 to 557
S22Rear fog lamp switch549 to 551
S24Air conditioning blower switch904 to 911
S29Coolant temperature switch118, 137, 357, 942, 957, 972
S30Left front heating mat switch660 to 662
S31Rear left door contact switch591
S32Rear right door contact switch592
S33Traction control switch1130, 1131
S37Window lifter switch868 to 894
S37.1Left window lifter switch868 to 870
S37.2Right window lifter switch886 to 888
S37.3Left rear window lifter switch874 to 876
S37.4Right rear window lifter switch892 to 894
S37.5Safety switch872, 873
S37.6Window anti-jam off switch890
S37.7Automatic window lifter control877 to 882
S39Left rear door window lifter switch878 to 880
S40Right rear door window lifter switch896 to 898
S41Driver door burglary locking switch800 to 802
S42Passenger door central locking switch805
S44Throttle valve switch316, 317
S47Driver door contact switch593, 594
S52Hazard warning switch569 to 573
S53First gear identification switch372
S55Right front heating mat switch664 to 666
S57Sun roof switch1170 to 1183
S63Computer switch
S63.1Function reset switch856
S63.2Clock hours adjustment switch857
S63.3Function select switch858
S63.4Clock minute adjustment switch859
S64Horn switch672
S68Outside mirror switch assy
S68.1Outside mirror adjustment switch638 to 640, 758 to 762
S68.3Left/right outside mirror switch637 to 641, 759 to 763
S68.4Parking position switch765
S82Washer fluid minimum capacity control switch736
S882 stage coolant temperature switch120, 121, 137, 138, 430, 431
S89Seat belt switch998
S93Coolant minimum capacity control switch737
S95Engine oil minuimum capacity control switch738
S98Headlamps levelling switch691 to 693
S99ZV driver door window lifter switch865
S100ZV passenger door window lifter switch883
S101Compressor switch926 to 928
S102Circulation switch918 to 920
S103Transmission temperature switch350
S104Kickdown switch493
S105Start-up assistance switch495 to 497
S106Economy power program switch492
S109Acceleration revolution pressure switch921
S115Coolant temperature switch487, 488
S116Stop lamp switch564, 565
S117Hydraulic pressure switch346
S120Engine compartment hood (anti-theft warning unit) switch835
S127Calibra tail gate central locking switch831
S128Coolant temperature switch936,937S131Defroster lever limit switch918
U2Computer851 to 862
U4ABS hydroaggregate1102 to 1122, 1146 to 1164
U4.1Pump motor relay1102, 1103, 1146, 1147
U4.2Solenoid valves relay1104, 1105, 1148, 1149
U4.3Pump motor1102,1146
U4.4Diode1105,1149
U4.5Left front solenoid valve1109,1153
U4.6Right front solenoid valve1111,1155
U4.7Rear axle solenoid valve1113,1157
U4.8ABS control unit1106 to 1122, 1150 to 1164
U4.9Solenoid valves plug1109 to 1113, 1153 to 1157
U5Check control display
U5.1Washer fluid minimum capacity telltale741
U5.2Oil minimum capacity telltale740
U5.3Coolant minimum capacity telltale739
U5.4Tail light & low beam telltale738
U5.5Stop light failure telltale737
U5.6Front brake lining telltale736
U12Filter heater
U12.1Temperature switch426, 452
U12.2Filter heater427, 453
U13Automatic transmission
U13.1Solenoid valve (shift 1)481
U13.2Solenoid valve (shift 2)482
U13.3Solenoid valve (lock up control)483
U13.4Solenoid valve (pressure control)484
U17Roof antenna amplifier795
V1Brake fluid test bulb diode712
V8Air conditioning compressor diode926
X1 onWiring connectorsVarious
X10Anti theft warning unit code837
X13Diagnostic link164, 165, 189, 190, 226, 270, 271, 258, 259,
309, 310, 370, 371, 343, 344, 473, 474, 573, 725, 836, 837, 860,
861, 1012, 1013, 1069, 1070, 1118, 1119, 1136, 1162, 1163
X15Octane number plug157, 158, 182, 183, 225, 226,
257, 258, 284, 285
X54Ignition coding plug310, 311, 1014, 1070, 1071
Y1Air conditioning compressor clutch925
Y4Headlamps washer solenoid valve620
Y5Fuel solenoid valve410, 445
Y7Fuel injection valves287 to 294,320 to 327,
384 to 391,1025 to 1032,1078 to 1089
Y10Hall sensor ignition distributor153 to 158
Y11Hot start solenoid valve375, 376
Y12Charging pressure control changeover valve377, 378
Y18Exhaust gas recirculation valve1093
Y23Inductive sensor distributor201 to 208
Y24Distributor (inductive discharge)
Y25Acceleration revolution solenoid valve155, 177
Y30Cold start acceleration solenoid valve 448
Y32Fuel injection valve212, 245
Y33Ignition distributor175 to 177, 268 to 270, 238 to 240,
301 to 303, 360 to 362
Y34Tank ventilation valve293, 331, 332, 379, 380,
1092, 1016, 1017,
Y35Circulation solenoid valve918
Y44Four wheel drive solenoid valve350
Y47Park brake shift lock lifting magnet469

REF•20Glossary of Technical Terms
A
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 cleanerA metal or plastic housing,
containing a filter element, which removes
dust and dirt from the air being drawn into the
engine.
Air filter elementThe actual filter in an air
cleaner system, usually manufactured from
pleated paper and requiring renewal at regular
intervals.
Allen keyA hexagonal wrench which fits into
a recessed hexagonal hole.
Alligator clipA long-nosed spring-loaded
metal clip with meshing teeth. Used to make
temporary electrical connections.
AlternatorA 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 sealerA 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.
AntifreezeA 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 thatwould tend to clog the radiator and coolant
passages and reduce cooling efficiency.
Anti-seize compoundA coating that
reduces the risk of seizing on fasteners that
are subjected to high temperatures, such as
exhaust manifold bolts and nuts.
AsbestosA 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.
AxleA 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.
AxleshaftA 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.
BBall bearingAn anti-friction bearing
consisting of a hardened inner and outer race
with hardened steel balls between two races.BearingThe 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.
Big-end bearingThe bearing in the end of
the connecting rod that’s attached to the
crankshaft.
Bleed nippleA 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 bleedingProcedure for removing air
from lines of a hydraulic brake system.
Brake discThe component of a disc brake
that rotates with the wheels.
Brake drumThe component of a drum brake
that rotates with the wheels.
Brake liningsThe 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 padsThe replaceable friction pads
that pinch the brake disc when the brakes are
applied. Brake pads consist of a friction
material bonded or riveted to a rigid backing
plate.
Brake shoeThe crescent-shaped carrier to
which the brake linings are mounted and
which forces the lining against the rotating
drum during braking.
Braking systemsFor more information on
braking systems, consult the Haynes
Automotive Brake Manual.
Breaker barA long socket wrench handle
providing greater leverage.
BulkheadThe insulated partition between
the engine and the passenger compartment.
CCaliperThe 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.
Brake bleeding
Bearing
Axle assembly
Anti-seize compound
Alternator (exploded view)
Air filter

Glossary of Technical Terms REF•23
JJump startStarting the engine of a vehicle
with a discharged or weak battery by
attaching jump leads from the weak battery to
a charged or helper battery.
LLoad Sensing Proportioning Valve (LSPV)A
brake hydraulic system control valve that
works like a proportioning valve, but also
takes into consideration the amount of weight
carried by the rear axle.
LocknutA nut used to lock an adjustment
nut, or other threaded component, in place.
For example, a locknut is employed to keep
the adjusting nut on the rocker arm in
position.
LockwasherA form of washer designed to
prevent an attaching nut from working loose.
MMacPherson strutA type of front
suspension system devised by Earle
MacPherson at Ford of England. In its original
form, a simple lateral link with the anti-roll bar
creates the lower control arm. A long strut - an
integral coil spring and shock absorber - is
mounted between the body and the steering
knuckle. Many modern so-called MacPherson
strut systems use a conventional lower A-arm
and don’t rely on the anti-roll bar for location.
MultimeterAn electrical test instrument with
the capability to measure voltage, current and
resistance.
NNOxOxides of Nitrogen. A common toxic
pollutant emitted by petrol and diesel engines
at higher temperatures.
OOhmThe unit of electrical resistance. One
volt applied to a resistance of one ohm will
produce a current of one amp.
OhmmeterAn instrument for measuring
electrical resistance.
O-ringA type of sealing ring made of a
special rubber-like material; in use, the O-ring
is compressed into a groove to provide the
sealing action.Overhead cam (ohc) engineAn engine with
the camshaft(s) located on top of the cylinder
head(s).
Overhead valve (ohv) engineAn engine with
the valves located in the cylinder head, but
with the camshaft located in the engine block.
Oxygen sensorA device installed in the
engine exhaust manifold, which senses the
oxygen content in the exhaust and converts
this information into an electric current. Also
called a Lambda sensor.
PPhillips screwA type of screw head having a
cross instead of a slot for a corresponding
type of screwdriver.
PlastigageA thin strip of plastic thread,
available in different sizes, used for measuring
clearances. For example, a strip of Plastigage
is laid across a bearing journal. The parts are
assembled and dismantled; the width of the
crushed strip indicates the clearance between
journal and bearing.
Propeller shaftThe long hollow tube with
universal joints at both ends that carries
power from the transmission to the differential
on front-engined rear wheel drive vehicles.
Proportioning valveA hydraulic control
valve which limits the amount of pressure to
the rear brakes during panic stops to prevent
wheel lock-up.
RRack-and-pinion steeringA steering system
with a pinion gear on the end of the steering
shaft that mates with a rack (think of a geared
wheel opened up and laid flat). When the
steering wheel is turned, the pinion turns,
moving the rack to the left or right. This
movement is transmitted through the track
rods to the steering arms at the wheels.
RadiatorA liquid-to-air heat transfer device
designed to reduce the temperature of the
coolant in an internal combustion engine
cooling system.
RefrigerantAny substance used as a heat
transfer agent in an air-conditioning system.
R-12 has been the principle refrigerant for
many years; recently, however, manufacturers
have begun using R-134a, a non-CFC
substance that is considered less harmful tothe ozone in the upper atmosphere.
Rocker armA lever arm that rocks on a shaft
or pivots on a stud. In an overhead valve
engine, the rocker arm converts the upward
movement of the pushrod into a downward
movement to open a valve.
RotorIn a distributor, the rotating device
inside the cap that connects the centre
electrode and the outer terminals as it turns,
distributing the high voltage from the coil
secondary winding to the proper spark plug.
Also, that part of an alternator which rotates
inside the stator. Also, the rotating assembly
of a turbocharger, including the compressor
wheel, shaft and turbine wheel.
RunoutThe amount of wobble (in-and-out
movement) of a gear or wheel as it’s rotated.
The amount a shaft rotates “out-of-true.” The
out-of-round condition of a rotating part.
SSealantA liquid or paste used to prevent
leakage at a joint. Sometimes used in
conjunction with a gasket.
Sealed beam lampAn older headlight design
which integrates the reflector, lens and
filaments into a hermetically-sealed one-piece
unit. When a filament burns out or the lens
cracks, the entire unit is simply replaced.
Serpentine drivebeltA single, long, wide
accessory drivebelt that’s used on some
newer vehicles to drive all the accessories,
instead of a series of smaller, shorter belts.
Serpentine drivebelts are usually tensioned by
an automatic tensioner.
ShimThin spacer, commonly used to adjust
the clearance or relative positions between
two parts. For example, shims inserted into or
under bucket tappets control valve
clearances. Clearance is adjusted by
changing the thickness of the shim.
Slide hammerA special puller that screws
into or hooks onto a component such as a
shaft or bearing; a heavy sliding handle on the
shaft bottoms against the end of the shaft to
knock the component free.
SprocketA tooth or projection on the
periphery of a wheel, shaped to engage with a
chain or drivebelt. Commonly used to refer to
the sprocket wheel itself.
Starter inhibitor switchOn vehicles with an
O-ring
Serpentine drivebelt
Plastigage
REF