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Diagnostic Manual, Engines, Volume 2

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 1.2 HFM Sequential Multiport Fuel Injectin/Ignition System (HFM-SFI)   >   24 Electrical Test Program - Ignition System Test


Electrical Test Program - Ignition System Test

Test scope
Test connection
Test condition Nominal value Possible cause/Remedy
1.0   Engine control
module (N3/4)
Voltage supply, circuit 30

33
(1.33)
N3/4



40
(1.40)
Ignition: ON 11 - 14 V 1.1
1.1   Ground wire N3/4

33
(1.33)


X11/4

2
Ignition: ON 11 - 14 V Wiring,
Ground, component compartment
- right (W16/4),
1.2
1.2   Voltage supply, circuit 30 X11/4

1


N3/4

40
(1.40)
Ignition: OFF 11 - 14 V Wire to terminal block X4/22,
2.0 1 1 0
1 1 1 		Engine control module (N3/4)
Voltage supply, circuit 87U

32
(1.32)
N3/4



39
(1.39)
Ignition: ON 11 - 14 V 2.1
2.1   Electronics ground N3/4

32
(1.32)


X11/4

2
Ignition: ON 11 - 14 V Wiring,
Electronics ground, component compartment - right (W16/6),
2.2
2.2   Voltage supply, circuit 87 X11/4

1


N3/4

39
(1.39)
Ignition: ON 11 - 14 V Wiring,
Overvoltage protection relay
module (K1/2),
Ignition/starter switch (S2/1).
3.0   Engine control
module (N3/4)
Voltage supply, circuit 87

66
(2.22)
N3/4



27
(1.27)
Ignition: ON 11 - 14 V Wiring,
Fuse,
Overvoltage protection relay
module (K1/2),
3.1
3.1   Electronics ground N3/4

66
(2.22)


X11/4

2
Ignition: ON 11 - 14 V Wiring,
Electronics ground, component compartment - right (W16/6),
4.0 0 5 5
0 5 6
0 5 7 		Ignition coil (T1/1)
Voltage supply

Up to end of M.Y. 1995


As of M.Y. 1996

33
(1.33)





33
(1.33)
N3/4




N3/4



65
(2.21)





53
(2.9)
Ignition: ON

Starter: Crank 		11 - 14 V

> 6 V 		Wire to T1/1,
Ignition coil T1/1,
Engine control module (N3/4).




Fuse,
Ignition coil T1/1,
Engine control module (N3/4).
5.0 0 5 8
0 5 9
0 6 0 		Ignition coil (T1/2)
Voltage supply

Up to end of M.Y. 1995


As of M.Y. 1996

33
(1.33)





33
(1.33)
N3/4




N3/4



53
(2.9)





65
(2.21)
Ignition: ON

Starter: Crank 		11 - 14 V

> 6 V 		Wire to T1/2,
Ignition coil T1/2,
Engine control module (N3/4).




Fuse,
Ignition coil T1/2,
Engine control module (N3/4).
6.0 0 6 4
0 6 5
0 6 6 		CKP sensor (L5) and magnet for CKP sensor on flexplate segment

73
(2.29)





73
(2.29)
N3/4 2)




N3/4 3)



74
(2.30)





74
(2.30)
Starter: Crank







Starter: Crank

Engine: at Idle
Signal, see
Figure 1






> 0.4 V~

> 1 V~ 4) 		6.1 ,
Segments (magnets) on starter ring gear.
6.1   Resistance of L5

73
(2.29)
N3/4



74
(2.30)
Ignition: OFF
Unplug connector 2 on engine control
module (N3/4). 		700 - 1400 Wiring,
6.2
6.2   Insulation of L5

32
(1.32)
N3/4



74
(2.30)
Ignition: OFF
Unplug connector 2 on engine control
module (N3/4). 		> 20 k L5.
7.0 0 6 7 CMP sensor (L5/1)

63
(2.19)




63
(2.19)
N3/4 2)



N3/4 3)



52
(2.8)




52
(2.8)


Engine: at Idle




Engine: at Idle 		Signal, see
Figure 3.





> 0.2 V~ 4) 		7.1 ,
Check distance between sensor (L5/1) and pickup (Refer to SMS, Engine 111, Engine Combustion,
Job No. 15-2143).
7.1   Resistance of L5/1

63
(2.19)
N3/4



52
(2.8)
Ignition: OFF
Unplug connector 2 on engine control
module (N3/4). 		900 - 1600 Wiring,
7.2
7.2   Insulation of L5/1

32
(1.32)
N3/4



52
(2.8)
Ignition: OFF
Unplug connector 2 on engine control
module (N3/4). 		> 20 k L5/1.
8.0 0 6 7 Non-U.S.A vehicles only.
Continue to next step
 

 

 

 
  		 
8.1   Non-U.S.A vehicles only.
Continue to next step
 

 

 
   
 
9.0 0 5 5
0 5 6
0 5 7 		Closure duration for ignition coil (T1/1)

Up to end of M.Y. 1995

As of M.Y. 1996



65
(2.21)





53
(2.9)
N3/4 2)




N3/4 2)




39
(1.39)





39
(1.39)
Starter: Crank

Engine: at Idle



20 - 100 ms

4 - 6 ms



6.0 ,
Engine control module (N3/4).




9.1

  Testing with multimeter: T1/1

Up to end of M.Y. 1995

65
(2.21)






53
(2.9)
N3/4 3)





N3/4 3)





39
(1.39)






39
(1.39)
Ignition: ON

Starter: Crank







0 V

0.3 - 0.5V





T1/1,
< 0.3 V: Open circuit in wire
from T1/1 to N3/4,
> 0.5 V: T1/1.
10.0 0 5 8
0 5 9
0 6 0 		Closure duration for ignition coil (T1/2)

Up to end of M.Y. 1995


As of M.Y. 1996

53
(2.9)





65
(2.21)
N3/4




N3/4



39
(1.39)





39
(1.39)
Starter: Crank

Engine: at Idle 		20 - 100ms

4 - 6 ms 		6.0 ,
Engine control module (N3/4).
10.1   Testing with multimeter: T1/2

Up to end of M.Y. 1995



As of M.Y. 1996

53
(2.9)






65
(2.21)
N3/4





N3/4



39
(1.39)






39
(1.39)
Ignition: ON

Starter: Crank 		0 V

0.3 - 0.5 V 		T1/2,
< 0.3 V: Open circuit in wire
from T1/2 to N3/4,
> 0.5 V: T1/2.
11.0 0 5 5
0 5 6
0 5 7 		Primary voltage
of ignition coil (T1/1) for
cylinder no. 1 and 4

Up to end of M.Y. 1995


As of M.Y. 1996


65
(2.21)






53
(2.9)

N3/4





N3/4




39
(1.39)






39
(1.39)
Note to Test connection:
Primary pattern, measurement range
400 V, duration 100%, voltage signal pick-up connected to T1/1.

Starter: Crank








200 - 350V 		11.1 ,
Engine control module (N3/4).
11.1 1 0 7 Primary winding of T1/1 and T1/2

Up to end of M.Y. 1995


As of M.Y. 1996

65
(2.21)





65
(2.21)
N3/4




N3/4



53
(2.9)





53
(2.9)
Ignition: OFF 0.9 - 1.9 5) T1/1 or T1/2.
12.0 0 5 8
0 5 9
0 6 0 		Primary voltage
of ignition coil (T1/2) for
cylinder no. 2 and 3
Up to end of M.Y. 1995


As of M.Y. 1996

53
(2.9)





65
(2.21)
N3/4




N3/4



39
(1.39)





39
(1.39)
Note to Test connection:
Primary pattern, measurement range
400 V, duration 100%, voltage signal pick-up connected to T1/2.

Starter: Crank








200 - 350V 		11.1 ,
Engine control module (N3/4).
13.0 0 5 5
0 5 6
0 5 7 		Firing voltage
of ignition coil (T1/1) for
cylinder no. 1 and 4 		 
Engine analyzer
Note to Test connection:
Secondary pattern, measurement range
20 kV, duration 100%, voltage signal pick-up connected to ignition coil (T1/1).

Starter: Crank










8 - 30 kV 		13.1 ,
Spark plug cables,
Spark plug connector,
Spark plugs,
N3/4.
13.1   Secondary winding of T1/1
ter. 4a
T1/1

ter. 4b
Unplug both ignition cables on T1/1.
5.2 - 8.5 k T1/1.
14.0 0 5 8
0 5 9
0 6 0 		Firing voltage
of ignition coil (T1/2) for
cylinder no. 2 and 3

 
Engine analyzer


 
Note to Test connection:
Secondary pattern, measurement range
20 kV, duration 100%, voltage signal pick-up connected to ignition coil (T1/2).

Starter: Crank










8 - 30 kV 		14.1 ,
Spark plug cables,
Spark plug connector,
Spark plugs,
Engine control module (N3/4).
14.1   Secondary winding of T1/2
ter. 4a
T1/2

ter. 4b
Unplug both ignition cables on T1/2.
5.2 - 8.5 k T1/2.
2) Test with oscilloscope.
3) Test with multimeter only if oscilloscope is unavailable.
4) Voltage increases with increasing rpm.
5) Resistance of coil T1/1 and T1/2. Resistance of single coil is 0.3 - 0.6



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