1988 CITROEN CX Service Manual

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.

.21.31 1
CX 20 829 A5
CX 22 J6T A 500
8531

DUCELLIER : 525 368 DUCELLIER : 525 541
D 59
BOSCH : 0227 100 111 DUCELLIER : 521 013
DUCELLIER : 520 007
MARELLI : 6 F $ 750 92 AE
IER : 520 015
l-3-4-2
0,82Q + 10% 6000 Cl ck 5 % 825OQ f 10%
1 -+ I,3 mdaN
J6T A 500
480 mm 615Q
270 mm 310 0
300 mm
350 Q
425 mm 825 Q
500 mm 900 fl
8531

/
I 21.14 1
121.13
1 l&2
6

DUCELLIER : 525 368
DUCELLIER : 525 541
R 303
D 59
BOSCH H7 DC
CHAMPION BNSY EYQUEM 755 LJS
EYQUEM 755 WS
BOSCH: 0227 100 111
DUCELLIER : 520 007 c 022
D 017
:HAMPION S 281 YC CHAMPION S279 YC
EYQUEM C72 LJS
BOSCH: 227 190 111
DUCELLIER : 521 013
MARELLI : 6 F $ 750 92 AE
SOLEX : 18 10 001
BOSCH : 0221 122 317 BOSCH : D 221 100 352
DUCELLIER : 5200 15 DUCELLIER : 520 015
l-3-4-2
1111 %
DUCELLIER
BOSCH DUCELLIER BOSCH
0,Bfi f 5 % 0,82 Q f 10 % 6000 0 f 5 ‘96 8250n f 10%
M 14 x 1,25
/ “_ti” 1
2
3
4 16mm 0,6 -, 0,7 mm 1 --, 1,3 mdaN
I 8301 -T
+
8302-T
829 A5
J6T A 500
480 mm 6150
270 mm 310 n
300 mm 350 n
425 mm 825 fl
500 mm goon
853

8531