1988 CITROEN CX oil type

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.
‘

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

SPECIFICATION AND SPECIAL FEATURES
OF THE AIR SUPPLY SYSTEM
Engines types 829.A5 and J6T.A500 are fitted with a device regulating the temperature of intake air.
This device has been designed for maintaining a minimum temperature of the air drawn into the carburettor
It consists of a thermal sensor and a vacuum capsule operating a flap. Thermal source
The thermal sensor is located in the pipe connecting the air filter to the inlet manifold of the carburettor
This bi-metal type thermostat, is subjected to the inlet air temperature
It controls the opening of valves allowing passage for a depression towards the capsule
This depression is picked up by a union having a calibrated orifice, fitted to the pipe connecting the oil breather
to the intake manifold of the carburettor, and by a T-shaped union situated near the carburettor base plate, so
as to have an action over the engine load.
The thermal sensor allows the depression to circulate when the temperature is below 15°C and stops it when the
temperature exceeds 25°C. Vacuum capsule.
The capsule, located in the inlet of the air filter, is subjected to the depression. When energised, it operates a flap
which lets the heated air coming from a tapping located on the exhaust shield enter. At rest, the flap lets intake
air coming from behind the grill enter.

GENERAL FEATURES
OF THE TRANSISTORISED IGNITION SYSTEM
TRANSISTORISED IGNITION
PRINCIPLE OF OPERATION
The plug spark is triggered by distributor (1) which comprises a coil located inside the field of a magnetic circuit
permanent magnet. The magnetic circuit has four fixed branches and four movable branches driven by the distribu-
tor shaft.
When the movable branches, in their rotation, come opposite the fixed ones, a variation of the magnetic field is
brought and current is induced into the sensor winding.
This current, in turn, triggers electronic module (2)
which builds up the current in ignition coil (3) primary winding
and then cuts it off, thus creating a high tension current in the coil secondary winding and triggering a spark from
the plug selected by the distributor rotor arm. IGNITION DISTRIBUTOR (I!
The advance curves are specific for each engine type
N: Distributor rpm
D = Vacuum Dl, in m.bars A:
Distributor degrees 02, in mm.hg
Pick-up coil resistance: 1100 Q sr 10% (990 to 1210 02)
Setting the distributor static timing on the engine is impossible owing to design.
A revolution of the distributor is required to create a variation of the magnetic field which will send a signal to the
module. Consequently, when fitting a distributor, place it in mid-slot; start the engine and adjust the distributor
by means of a timing light or a diagnosis console.
The duration and amplitude of the signal depend on the speed, therefore the DWELL ratio
is not significant.
The air gap between the branches is non-adjustable and it cannot be measured ELECTRONIC MODULE (2)
Intended to operate with the magnetically-triggered distributor.
Do not carry out a check with an ohmmeter since the results would not be significant.
Do not operate the module without cooling (aluminium plate heat sink and heat conductor grease).
The operation of the ignition system is possible with the engine stopped: - connect an earthed sparking plug to
the coil HT lead; short ” + 12 volts” pulses on module red lead (path 5) (with all leads connected, cap lifted) will
generate a spark from the plug: simulation of a signal from the distributor pick up).
Do not operate the module and coil without a plug and HT lead, (It could result in the module being destroyed). IGNITION COIL (3)
The coil must not be kept alive under 12 volts without its module (overheating).
The coil current flow is generated by the module which then reduces it, prior to cutting it off when the engine
ignition timing occurs.
Only use a rev. counter with a UT induction clip.

CHECKING THE INTEGRATED ELECTRONlC
IGNITION (I.E.I.)
TEST PROCEDURE USING CONVENTIONAL EQUIPMENT
on the CX 2500 vehicle with M 25/659 type engine
l Checking the voltage in the secondary winding of each coil
0 Operating procedure: Disconnect one sparking plug and bring the end of the released wire 1 cm approx
from the crankcase. (Repeat the operation for each set of cylinders).
l Operate the starter motor:
if a spark occurs The incident is not to be attributed to the I.E.I.
Check the injection system, the valve timing, the rockers etc.
- examine the engine sparking plugs.
- inspect the circuit between the I.E.I. control unit white terminal 1 and the fuel
injection control unit terminal 15 for continuity: read 0 0, the connectors from
the control units being disconnected.
if no spark occurs The incident is due to the ignition system--ccarry on to next tests.
l Working on the primary winding of each coil
Operating procedure: Connect a 12V warning lamp of the Wedge base type between the negative and
0 the positive terminals of the coil (i.e. between terminals 1 and 3, connectors con-
netted to coil).
l Operate the starter motor:
if no regular breaks occur incident in the coil primary winding
or
incident in the E.C.U. control circuit.
if regular breaks occur incident in the secondary winding
The following checks are to be carried out with I.E.I. and fuel injection control units connectors disconnected.
l Checking the coil primary windings:
Operating procedure: Measure the resistance between terminals 1 and 9 of the I.E.I. control unit black
0 connector: Read = 2.5 0.
Warning: the ignition should be switched off.
If the reading is incorrect, investigate for a failure in this circuit.
l Checking the E.C.U. pick up sensors:
co Operating procedure: Measure the resistance between terminals 5 and 12 then 6 and 13 of the I.E.I.
control unit black connector: Read = 50 a.
l Checking the feed for the E.C.U. and earth connection, with ignition switched on
Operating procedure: Measure the voltage between terminals IO (white connector) and 2 (black con-
nector) of the I.E.I. computer: Read the battery voltage.
The same check should be carried out between terminals 2 (earth) and 11 of the black connector:
ignition switched on, starter motor operated, read the voltage.
69 l Check that the distance between the datum sensor and the flywheel ring is 1 mm + 0.5.
0 l Incident on the ignition circuit secondary winding: make sure that the resistance of each coil
winding is: 350014000 a.
8531

CHECKING THE I.E.I.
TEST PROCEDURE USING CONVENTIONAL EQUIPMENT
on the CX 2500 Turbo vehicle with M 25/662 type engine
0 Checking the voltage in the secondary winding of each coil
0 Operating procedure: Disconnect one sparking plug and bring the end of the released wire 1 cm approx
from the crankcase. (Repeat the operation for each set of cylinders).
0 Operate the starter motor,
if a spark occurs
if no spark occurs The incident is not to be attributed to the I.E.I.
Check the injection system, the valve timing, the rockers etc.
- examine the engine sparking plugs.
- inspect the circuit between the I.E.I. control unit white terminal 1 and the fuel
injection control unit terminal 15 for continuity: read 0 Q, the connectors from
the control units being disconnected.
The incident is due to the ignition system-carry on to next tests.
l Working on the primary winding of each coil
Operating procedure: Connect a 12V warning lamp of the Wedge base type between the negative and
the positive terminals of the coil (i.e. between terminals 1 and 3, connectors con-
netted to coil).
l Operate the starter motor,
if no regular breaks occur incident in the coil primary winding
or
incident in the E.C.U. control circuit.
if regular breaks occur incident in the secondary winding
The following checks are to be carried out with I.E.I. and fuel injection control units connectors disconnected.
0 Checking the coil primary windings:
Operating procedure: Measure the resistance between terminals 1 and 9 of the I.E.I. control unit black
0 connector: Read = 2.5 Q.
Warning: the ignition should be switched off.
If the reading is incorrect, investigate for a failure in this circuit.
l Checking the E.C.U. pick up sensors:
OI Operating procedure: Measure the resistance between terminals 5 and 12 then 6 and 13 of the I.E.I.
4
control unit black connector: Read 2: 5OQ
0 Checking the feed for the E.C.U. and earth connection, with ignition switched on.
d 5 Operating procedure: Measure the voltage between terminals 10 (white connector) and 2 (black con-
nectar) of the I.E.I. computer: Read the battery voltage.
The same check should be carried out between terminals 2 (earth) and 11 of the black connector:
ignition switched on, starter motor operated, read the voltage.
@ 0 Check that the distance between the datum sensor and the flywheel ring is 1 mm + 0.5.
0 * Incident on the ignition circuit secondary winding: make sure that the resistance of each coil
winding is: 350014OOOQ.

REPAIR OF THE HYDRAULIC SYSTEM
FITTING PRECAUTIONS
PRECAUTIONS TO BE TAKEN WHEN WORKING ON
THE HYDRAULIC UNITS OR THE SYSTEM
The correct functioning of the entire system presupposes perfect cleanliness of the fluid and the hydraulic
units. Stringent precaut!ons must therefore be taken when working on the hydraulic system and during the
storage of the fluid and components. 1. HYDRAULIC FLUID:
Mineral hydraulic fluid (LHM) is the only suitable type and must be used to the exclusion of all others in the hydrau-
lic system of the car.
This LHM fluid is green in co/our and similar to engine oil.
The use of any other would ruin the rubber rings and seals in the system. 2. RUBBER UNITS AND PARTS:
Suitable components are identified by their green co/our and may only be replaced by genuine replacement
components painted or marked in green.
All rubber components (seals, hoses, diaphragm, etc...) are of a special quality for use with LHM fluid and are
identified by their white or green colour. 3. STORAGE:
Components must be stored, full of fluid and blanked off. Like the piping, they must be protected against shock
and the ingress of dust.
Rubber tubing and joints must be stored away from dust, air, light and heat.
LHM hydraulic fluid must be stored in its original containers carefully sealed. We advise the use of one litre (for
topping up) or five litre cans (for refilling) to avoid having to keep opened containers. 4. CHECKS BEFORE CARRYING OUT WORK:
Before-working on the hydraulic system in case of faulty operation, ensure the following:
a) That the controls or the mechanical linkages of the units or the group of hydraulic units involved are
not stiff in operation
I I
b) and that the HP circuit is under pressure, as follows:
With the engine at idling speed:
- Unscrew the pressure-release screw on the pressure regulator by one turn to one turn and a half: a sound
of leakage should be heard from the regulator.
- Retighten the release screw: cut-out must occur which results in a reduction in the running noise emitted
by the H.P. pump.
If not, check in the following sequence:
- that there is sufficient fluid in the reservoir,
- that the reservoir filter is clean and in good condition,
- that the H.P. pump is primed and there is no air leak on the suction side of the pump,
- that the release screw of the pressure regulator is correctly tightened,
- that sealing ball (2) is in position, (see Fig. I and II, page 5).

ELECTRICITY
MA 510.00011 1
ELECTRICAL INSTALLATION GENERAL OUTLINES
PRESENTATION:
The electrical system operations are composed of:
- A main wiring diagram.
- A circuit diagram.
- Lists of parts,
harnesses,
earth connections,
connectors between harnesses.
- A fuse table.
A lamp chart.
- Various circuit and wiring diagrams for special functions or optional equipment.
I_
UTILISATION:
The wiring diagram indicates the location of the components, harnesses, earth connections and connectors
on the vehicle.
The circuit diagram presents the electrical circuits in a functional way.
- The components symbols in the circuit diagra*m are those shown on the symbol key (see pages 2 and 31.
- Several symbols can be used for a component and the item can be shownC.exploded on different lines
according to the functions.
- Switches are shown at rest, with vehicle stationary, and the doors closed.
- The switches must be moved from right to left.
- The position of a relay coil, generally to the left of the contact switch, is not compulsorily so.
- In cases where the selector switch is complex, the contact movements are shown in the manner to be
considered the most comprehensible.
- The electronic control units are not shown in detail.
Parts list: the parts are in the alphabetical order, and numbered.
The number of the item remains the same on all the diagrams provided the functron has not changed. The
parts list enables any item to be located on the wiring diagram (by means of letters and figures), and on the
circuit diagram (with a vertical line No). The identification of the connector and the ref. letter of the harness
attached to the part are also included in the parts list.
List of harnesses: it gives the position of electrical harnesses on the wiring diagram and the location of each
lead of this harness on the circuit diagram (capital letter in the middle of the wire).
List of earth connections: it indicates the location of the earth connections and the wires or connectors and
the connecting harnesses (letter CC m )), followed by a number).
List of harness inter connections : it indicates,
- the reference of the harness concerned,
- the type of end fittings: I, metal contact or connecting pin,
U, clip or socket,
- the colour of the wire insulator and the marking or sleeve colour code,
- the junction connector: number of channels, colour and channel involved,
- the location of this connector on the wiring diagram,
- the location of each channel of the connector on the circuit diagram.
The harnesses are described in alphabetic order.
8531 8532