Volvo 819 E - Renix-F

Group 28 Igni tion s ystems
Design and function Syst em descriptions
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UJ 105
RENIX- F
RENIX-F
B200K
(The above illus tr at io n and t he following text are based on the B200 K engine used in the 740)
The sys tem consis ts of an electronic co ntrol u nit (1) whi ch is supplied with engine speed and cranksha ft position sig-
nals
by an i ndu c tiv e speed/position pick- up !2). The pick -up detects the passage of a number of 'te eth' on the fly -
wheel ( 3) . The co ntro l unit is al so sup plied with i nf or mation on engine load through a vacuum line (4) co nne c ted to
the intake manifold, the pressure in which ac tu a te s a vacuum advance un it (5) in tegr al with th e unit .
The speed and l oad signals are pro cessed by th e co ntr ol unit electronics and compa red with the timing se tt ings
stored in the memory. Hav ing used the information to compute the op timum timing , the unit t ransmi ts co ntrol sig-
nals to an
integral power stage wh ich makes and breaks the current in the primary w i nding of the ignition coil!6) at
the correct ins tant , gene ratin g a high -tension curren t in the secondary . The HT pulse is fed to t he dist ribu t or (7) for
del ivery to th e appropria te spark plug (81 .
Apart from the rotor , the distr i butor con tain s no mechanical or electronic co mponents , its sole funct io n being to dis-
tribute the high -tens ion cur rent to the co rrect plug .
• At idling
speeds of less than 1000 rIm in, the contr ol unit advan c es t he timing by 5- to prevent adrop in speed when the AC system
is
sw itched on or when a drive position is selected on an automatic mode l.
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