BMW 5251 Service Manual page 356

I
lgnition
System
4
Normal combustion period at idle.
4
Normal oscilloscope pattern for ignition system at idle.
15. 15
4
lgnition voltage peaks at idle.
1. Normal ignition peaks.
2. Downward peak (arrow) is shortened (ignition coil is
defective).
3. Downward peak (arrow) is missing completely (ignition
coil is defective).
4
Defective ignition coil.
1. Short spark period.
2.
The spark voltage line (arrow) is very slight
<
Defective ignition coil.
1. Normal combustion period.
2. Absence of spark voltage line (arrow).
( r + ~ + ~ + ~ ( . ~ i + ~ / . ~ ~ i t l t ~ ~ ( t i t ~ l i i ~ ~ j t ~ ~ ~ i ~ i t t i i i ~ l
I W
1 0
ED 1 0 (0
I D U
10
11
70 0
sa,ma,
2
.
15
-
.
5
-
-
-
0
30
.
.
20
.
I 0
- -
0
i i i C i ; k i W * h u i M w i r i t i l ~ t i i i
110 1 0 00
ro w
M A,
30
2"
* : , : m u