electrical CITROEN CX 1988 Service Manual

USE OF THE MANUAL
PRESENTATION
The Repair Manual comes in a binder with a “Mu/to” type
mechanism to facilitate the filing of additive sheets
or the removal of a part for operation in the workshop.
The MECHANICAL COMPONENTS, PART 1 VOLUME (8531) covers operations on the MECHANlCAL
COMPONENTS and the BODYWORK which may be carried out by a general workshop.
It is divided into 15 chapters separated by vinyl tab inserts numbered @ to @
General
Engine
Fuel system-Carburettor
Ignition system
Clutch
Gearbox-Drive shafts
Source and reserve of pressure
Front axle Rear axle
Suspension - wheels - tyres
Steering
Braking system
Electrical equipment and radio
Heater, ventilation and air-conditioning
Bodywork
COMPOSITION OF A CHAPTER
Each chapter includes:
-
the list of operations in it,
-
the operations in numerical order.
OPERATIONS
The operation references are made up as follow: MA 100 - 00 II a
-
a) z T-r TiiTz
a) vehicle code letters: MA
b) three figure number identifying the assembly or the assembly part
c) figure indicating the type of operation:
-
the figures 000 indicate the vehicle specification
- the figures 00 indicate the assembly specification
- the figures 0 indicate checks and adjustments
- the figures 1 indicate removals and refittings
- the figures 2 indicate dismantling and re-assembly
-
the figures 3 indicate reconditioning
d) figure /I,... /2.../... standing for a variant,
e) letter: a, b, standing for an evolution
rious operations are presented:
1’ either through photos, drawings and texts,
hrough photos, drawings and symbols.
‘!%.OSSARY has been placed at the beginning of each volume for this purpose.
e glossary (the one in the Mechanical Components volume is different from the one in
caning for each symbol has been translated into nine languages.
kts in a removable set of “plastic” sheets bound with one manceuvrable me
ion of one or several pages (and obtain photocopies from them, for instance). the Bodywork volur nel,
‘tal r ing to facilitate the
85 31

6
n
PROTECTION OF THE ELECTRICAL UNITS
8531

PROTECTION OF THE ELECTRICAL COMPONENTS
PRECAUTIONS TO BE TAKEN WHEN CARRYING OUT AN OPERATION ON THE VEHICLE
It is essential to avoid actrons which may damage the electrical or the electronic equipment or create a short circuit
(wrth subsequent risk of fire or accident).
Battery:
a) First disconnect cable clamp from the battery negative terminal, earthed, then from the positive post.
b 1 Before tightening the negative clamp to the battery (the negative lead should be connected last), ensure that there
is no short circuit (bright sparks or arcs).
Small sparks may occur due to the interior lamp (door open), door locking device, clock or components having
remained in operation.
c 1 Make sure that the terminals are properly connected. Clamps and terminals should be clean and correctly tightened.
d ) When recharging the battery, disconnect the two clamps first.
e) Do not reverse the negative and positive clamps on the battery. (This could destroy the alternator diodes).
Fuses:
a 1 Fit the correct type of fuses: use the fuses specified for the protected devices
b 1 Take the added accessories and the functions into consideration.
Charging circuit:
,a 1 Do not run the alternator unless it is connected to the battery. Do not disconnect the battery when the alternator
is rotating.
b 1 Ensure that the regulator is correctly earthed.
c ) Do not interchange the leads connected to the regulator, (charge detection warning lamp and excitation are specific).
d ) Do not connect a suppressor capacitor to the regulator without taking precautions or following proper
instructions.
e 1 Do not use an electric welding equipment on the vehicle without having first disconnected the alternator, the regula-
tor and the battery (insulate the two terminals).
f 1 Do not R check )) the operation of an alternator by short circuiting the positive and ground terminals, which may
destroy the diodes.
Starting the engine:
Do not use a booster or a 24-volt battery. Only use a correctly charged 12-volt battery (a higher capacity battery may
be utilised). Otherwise, risk of deterioration of the ignition module or any other electronic control units. If the starter
is needed for starting the engine, without running it, it is necessary to disconnect datum and flywheel sensors on the
All Electronic Ignition, or the primary lead of the coil on any other type of ignition.
Ignition:
a 1 Do not connect a suppressor capacitor to the negative terminal of the coil.
b 1 Do not operate the module if its radiator is not connected to the earth.
c 1 Fit the radio suppressor capacitors recommended by the factory.
d 1 Never operate the ignition system while the HT circuit is open. Connect the HT leads to earth
e) Only use rev. counter having a HT sensor, (never puncture HT leads).
0.1. bulb:
a) Never replace a 01. bulb with the headlamp switched on. If the headlamps have been in use, allow them to cool down.
b) Do not touch a 0.1. bulb with bare fingers. Any fingerprints must be cleaned with soapy water and the bulb dried
with a dry lint-free cloth.
Checks :
a) Preferably use a high resistance (> 10 k Q VI voltmeter or a battery-operated ohm-meter
b) Take care not to use instruments taking their power from the mains.
Electronic components:
a) Avoid overvoltages due to a badly insulated charger, electric arcing or connections to the coil.
The units such as regulator, ignition module, tachometer, windscreen wiper timer, flasher unit, clock, radio, oil gauge
unit, door lock control unit, etc. comprising electronic components may be deteriorated.
b) The electronic components should not be placed or operated under a temperature exceeding 80°C.
c) Always switch off instruments or electronic control units before connecting or disconnecting them.
‘

“LE JETRONIC” ELECTRONIC FUEL
INJECTION SYSTEM
“LE Jetronic” system
The “LE Jetronic” IS a fuel injectiorl system which injects Intermittently petrol, at low pressure, into the inlet rnanifold
The main characteristic of the device IS to rneter drrectly the air drawn in by the engine, which is the only reference
for the fuel quantity to be injected. The fuel metering IS carried out by electro-magnetically triggered injectors. These
are under a constant fuel pressure.
The quantrty of fuel injected depends on how long the Injectors remain open. The duration of opening is optimally
determined for each engine operating phase by an electronic control unit, from data supplied by various electric
sensors.
The “LE Jetronic” device is composed of:
No.
COMPONENTS MADE BY REFERENCE
142 Electronic Control Unit (E.C. U.) BOSCH 0280 000 300
192 Throttle spindle switch cc 0280 120 301
280 Supplementary air control (C 0280 140 172
302 Flow meter ,, 0280 202 021
345 Electrovalve ,) 0280 141 011
576 Injector n 0280 150 254
683 Electrical fuel pump
)> 0580 464 008
731 Relay D 0280 230 009
841 Water temperature sensor D 0280 130 026
F Fuel filter N 0450 905 002
R Fuel regulator pressure ,) 0280 160 216

“LE Jetronic” system
The “LE Jetronic” is a fuel injection system whrch injects intermittently petrol, at low pressure, into the Inlet manrfold
The main characteristic of the device is to meter directly the air drawn In by the engine, which is the only reference
for the fuel quantity to be injected. The fuel metering is carried out by electro-magnetically triggered injectors. These
are under a constant fuel pressure.
The quantity of fuel injected depends on how long the injectors remain open. The duration of opening IS optimally
determined for each engine operating phase by an electronic control unit, from data supplied by various electric
sensors.
The “LE Jetronic” device is composed of:
No. COMPONENTS MADE BY REFERENCE
142 Electronic Control Unit (E.C.U.) BOSCH 0280 000 224
192 Throttle spindle switch 0
0280 120 313
280 Supplementary air control u
0280 140 178
302 Flow meter ,)
0280 202 061
345 Electrovalve ,,
0280 141 011
575 Cold start injector n
0280 170 409
576 Injector >,
0280 150 200
683 Electrical fuel
pump 1,
0580 464 008
731 Relay >,
0280 230 009
841 Coolant temperature sensor 1)
0280 130 026
870 Slow thermal switch ,>
0280 130 214
F Fuel filter ),
0450 905 002
R Pressure regulator ,)
0280 160 216

CHECKING AND ADJUSTING
THE INJECTION SYSTEM
II. - INSPECTION AND TIMING OF THE “ROT0-DIESEL” INJECTION PUMP
Raise the LH side of the vehicle and support it on
stands.
Disconnect the battery negative lead.
Engage the 5th gear. Rotate the engine by turning the
wheel.
Set the No. 1 cylinder to the initial timing point,
Fig.1.
(look into the oil filter orifice).
- place cylinder No. 1 valves in the rocking position;
turn the crankshaft by one turn in the normal direc-
tion of engine rotation.
- align marks on the flywheel and on the crankcase
(++I.
- turn the crankshaft back through a quarter of a turn.
Remove either the plug (with a 32 mm ring spanner)
or the inspection plate depending on the type of the
pump.
Refit, Fig II or Ill, according to pump:
- the feeler,
- the support for the dial-gauge.
- the dial-gauge equipped with its right-angled lever.
Finding the pump internal timing point:
- turn the crankshaft in the direction of rotation until
the large pointer on the dial indicator starts moving
in the opposite direction.
- set “0” mark on the dial-gauge in line with the large
pointer.
Checking the injection pump timing:
- rotate the crankshaft by a quarter turn in the oppo-
site direction to its direction of rotation.
- turn back in the normal direction of rotation until the
“0” mark on the dial-gauge has been reached.
- in that position, marks (-1 and (c) should be in line,
Fig. I.
If not, re-check the timing. Timing the injection pump:
- set the engine to the initial trming point, Fig. I.
- turn the crankshaft by 114 turn in the opposite direc-
tion to normal direction of ro’tatron, then turn back
in the direction of rotation to bring marks t-+) and
+-I opposite.
Adjusting the pump timing, Fig. Ill:
Slacken off the injector pipe connections and the 4
attachment points.
Bring the pump to the injection point with the feeler
at the base of V-shaped groove (timing point).
Set the “0” mark on the dial opposite the needle on
the dial-gauge. Orientate the pump casing towards the
engine.
Slowly turn back to the injection point (needle facing
the “0” mark on the dial), by moving the pump
casing away from the engine (in the opposite direc-
tion to engine rotation).
Tighten the pump fixing nuts to 2.4 mdaN. During
this operation, the needle should not move.
Check the pump timing
Remove the timing tools.
Refit the plug, (tighten to 2 mdaN), or the inspec-
tion plate.
Seal the injection pump plug.
Tighten the injector pipe connections to 2 mdaN.
Reconnect the battery negative cable
Switch on the ignition (electrical STOP solenoid exci-
tation) and prime the fuel circuit using the manual
pump (5) located on the filter.
Fully depress the accelerator pedal to facilitate the
engine bleeding and start.
Note: the initial timing point corresponds to:
3.24 -L- 0.05 mm BTDC: M 25/648
4.32 + 0.05 mm BTDC: M 25/660 DPA pump
4.71 f 0.05 mm BTDC: M 25/660 DPC pump
8531

Raise the R.H side of the vehicle and support it on
stands.
Disconnect the negative lead from the battery
Engage the highest gear. Using the road wheel, turn
the engine.
Set No. I cylinder to the initial timing point, Fig. I.
(look into the oil filler hole)
- Bring cylinder No. 1 valves into the rocking position
by rotating the engine one turn clockwise.
- Marks- and- should be aligned.
Remove:
- the road wheel,
- the wheelarch lining,
- the belt upper protection cover.
Loosen:
- the injection pump drrvrng pinion nut,
- the belt tensioner nut,
- compress the spring of the tensioner.
Remove:
- the pinion nut,
- the injection pump driving belt. MANDATORY: TO AVOID THE PUMP BEING
DAMAGED INTERNALLY WHEN REMOVING
THE DRIVING PINION, PULLER REF. H AND ITS
NUT J FROM TOOL BOX 6028.T MUST BE
USED.
Fit the nut and clamp of tool 6028.T, Fig. II.
Slacken the nut of tool 6028.T until the injection
pump drive shaft starts moving.
Disconnect the electrical STOP solenoid
Uncouple:
- the accelerator cable,
- the fast idling cable,
- the fuel supply pipe,
- the fuel return pipe.
DPC injection pump, Fig. ill:
Disconnect from the overfuelling circuit:
- the diesel fuel return pipe (21,
- the air pipe (I 1.
Push the diesel fuel filter to one side
Remove:
- the spring,
- the injectors sets of feed pipes,
- the pump fixing nuts (3) Fig. IV.
by means of a 73 mm A/F open spanner
and a 6 mm hexagon Allen key.

2 IVIA
422.1/l OVING AND REFITTING A REAR AXLE ARM
REMOVAL
Raise the rear of the vehicle and support it on stands,
wheels free.
Remove the road wheel.
Release the pressure in the hydraulic systems.
Remove protection plate (I 1, Fig. I.
Vehicle having the A.B.S. fitted, Fig. II :
Withdraw sensor (3) and push aside the metal panel
and sensor, liberating the electrical harness from the
retaining clips.
Remove suspension cylinder (5), Fig. Ill.
(As explained in @ MA 433. l/2/.
Take off fixing lug (41, Fig. Ill.
Uncouple:
- brake hose (21, Fig. I,
- the anti-roll bar, Fig. Ill. In order to do so, extract
screws (6) and (7) and keep adjustment shims and
washers c(a)) and ccbal.
Take off nut (8) 24 mm A/F, Fig. IV.
Free the shaft and remove the arm. REFITTING
Position the axle arm (the thinner thrust cup (9) :
9.34 mm thick at CCCH facing the interior of the
vehicle, -+ l/87), Fig. V).
l/87 -+ the thrust cups are identical and the adjust-
ment is effected by means of shims facing the exte-
rior of the vehicle.
Return the shaft to its original location.
Place nut (8), new NYSLTOP nul, Fig. IV.
Tighten to 13 mdaN.
Recouple the anti-roll bar, Fig. Ill. Add the screws (6)
and (7) together with the adjustment shims and
washers found at c(a)) and c(b)) on dismantling.
Tighten screws (7) to 6 mdaN and (6) to 10 mdaN.
Reconnect brake hose (2) Fig. I, fitted with a NEW
sleeve seal. Tighten it.
Refit fixing lug (41, Fig. Ill.
Locate suspension cylinder (51, Fig. IV.
(See @ MA 433. l/2/.
ABS vehicle, Fig. II :
Refit sensor (31, (grease the outside of the sensor with
MOBIL TEMP No. I).
Tighten the screw to 1 mdaN.
Reassemble:
- protection plate (I 1, Fig. I,
- the road wheel.
Lower the vehicle to the ground.

REMOVING AND REFITTING A SWIVEL
REFITTING Replace, Fig. IV:
Wipe the ball-joint fixings and location, do not use - flexible pipe (I I) into its fixing bracket,
solvent. - washer (I 0).
Recouple the upper ball-joint with the swivel. Tighten nut (9) to 2.2 mdaN.
Refit, Fig. I: Recouple:
- washer (I),
- Fig. IV, connection (I 2) provided with a new sea/.
- nut (2).
- Fig. V, the steering ball-joint.
Tighten to 7 mdaN (New NYLSTOP nut).
Refit:
Introduce the drive-shaft end into the wheel hub - washer (I 31,
(lubricate the hub seal lips). - nut (14) (New NYLSTOP one).
Couple up the lower ball-joint. Tighten to 6 mdaN.
Tighten to 6 mdaN the new NYLSTOP nut. Reconnect:
-cup (171,
Reconnect the brake pad wear warning lamp harness. - spring (I 61,
-cable (15).
Refit, Fig. II and Ill:
Adjust the handbrake (as indicated in @ 454.011).
- electrical harness fixing bracket (4).
- earth lead (5).
- screw (3). Put the drive-shaft nut into place.
- metal panel (6). (Faces and threads lubricated).
Lock the hub, utilizing tool 6310-T Fig. VI.
ABS vehicles, Fig. Ill:
Tighten to 37.5 mdaN.
Reinstall sensor (7) (spread MOB/L TEMP No. 1
grease over the outside of the sensor.
Bleed the front brakes (see @ 453.0/l/.
Tighten screw (8) to 1 mdaN.
Fit the wheel.
Lower the vehicle to the ground.
8531-8532

REMOVING AND REFITTING THE
DRIVE SHAFT ASSEMBLIES
REFITTING
Lubricate the wheel hub seal lips.
Fitting the LH drive-shaft assembly:
install:
- a NEW circlip (21,
- O’ring seal (I).
on the shaft, Fig. I.
Turn the steering through full lock to the left.
Insert the shaft splines home in the sun gear.
Make sure that the circlip is fully entered into its
location within the sun gear by pulling the shaft.
Engage the drive-shaft into the wheel hub.
Fitting the RH drive-shaft assembly:
Turn the steering through full right lock.
Slide the shaft into bearing (3).
Install:
the dust cover (5)
- ring (41,
- o’ring seal (3).
on the drive shaft, Fig. II
Slightly grease the bearing outer ring (7) before ente-
ring it into bearing (8). Fig. Ill.
Introduce the drive-shaft into the hub.
Swivel tie rods (6) by a half turn so that they can grip
the bearing outer ring.
Tighten nuts (9) to 1 mdaN. Couple up the lower ball-joint, (Wipe the ball-joint
fixing but do not use solvent).
Tighten to 6 mdaN the (NEW NYLSTOP) nut.
Recouple link rod (IO) with the anti-roll bar. (Wipe
the ball-joint fixing, do not use solvent).
Tighten to 4.7 mdaN the NEW NYLSTOP type nut.
Refit the suspension cylinder swivel ball and pin (14).
Reconnect the electrical harness to the brake pad
wear warning lamp (I I).
Reinstall the brake disc cooling plate (I 3)
Fit the drive-shaft nut (with faces and threads
lubricatedl.
Clamp the wheel hub with tool 6310-T.
Tighten to: 37.5 mdaN.
Replace:
- nut lock (121,
- the pin,
- the road wheel
Lower the vehicle to the ground
3tc 8531