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Diagnostic Manual, Engines, Volume 2

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 1.2 HFM Sequential Multiport Fuel Injectin/Ignition System (HFM-SFI)   >   23 Electrical Test Program - Sequential Multiport Fuel Injection System Test


Electrical Test Program - Sequential Multiport Fuel Injection System Test

Test scope Test connection Test condition Nominal value Possible cause/Remedy
1.0   Engine control module (HFM-SFI) (N3/4)
Voltage supply
Circuit 30

33 (1.33)
N3/4




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

33 (1.33)



X11/4


2
Ignition: ON 11 - 14 V Ground wire,
Ground (output 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 (HFM-SFI) (N3/4)
Voltage supply
Circuit 87

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 Wire,
Ground (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
Wires,
Overvoltage protection relay
module (K1/2),
Ignition/starter switch (S2/1).
3.0   Engine control module (HFM-SFI) (N3/4)
Voltage supply
Circuit 87

66
(2.22)
N3/4




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

66
(2.22)



X11/4


2
Ignition: ON 11 - 14 V W16/6.
4.0 0 0 9
0 1 0 		Hot film MAF sensor (B2/5)
with 4-pole connector
Voltage at hot film

71
(2.27)
N3/4




49
(2.5)
Engine: at Idle

Engine coolant
temperature >70°C 		0.8 - 1.1 V 2) Wiring,
4.1 ,
4.2 ,
Intake air leak,
B2/5.
4.1   Hot film MAF sensor (B2/5)
Voltage supply

71
(2.27)
N3/4




39
(1.39)
Ignition: ON 11 - 14 V Wiring,
N3/4.
4.2 0 0 9
0 1 0 		Ground for hot film MAF sensor (B2/5)

66
(2.22)
N3/4




71
(2.27)
Ignition: OFF
Disconnect connector 2 on N3/4. 		< 20 Ground wire.
5.0   Hot film MAF sensor (B2/5)
with 5-pole connector
Voltage at hot film

71
(2.27)
N3/4



49
(2.17)
Ignition: ON
Engine: at Idle
Engine coolant
temperature >70°C 		0.9 - 1.1 V 2)
1.3 - 1.7 V 		Wiring,
5.1 ,
Intake air leak,
B2/5
5.1   Hot film MAF sensor (B2/5)
Voltage supply

66
(2.22)
N3/4



61
(2.17)
Ignition: ON 4.7 - 5.2 V Wiring,
N3/4
5.2 ,
5.2   Ground for hot film MAF sensor (B2/5)
3
B2/5

4
Disconnect connector on B2/5 and measure directly at sockets 3 and 4.
Ignition: ON 		4.7 - 5.2 V Fuse,
Wiring,
5.3 ,
5.3   Voltage supply N3/4

66
(2.44)





B2/5
2
(2)
Disconnect connector on B2/5 and place positive lead directly on socket 2 (rt/bl).
Ignition: ON 		11 - 14 V Fuse,
Wiring,
Relay module (K40)
6.0 0 7 6 FP relay module (K27)

Control signal

32
(1.32)
N3/4




29
(1.29)
Engine: Start 6 - 14 V
while cranking 		6.1 ,
N3/4.
6.1   Current draw


29
(1.29)
N3/4




39
(1.39)
Ignition: ON 0.1 - 0.3 A Wiring,
FP relay module (K27).
7.0 1 0 1 Starter signal
Circuit 50

32
(1.32)
N3/4




21
(1.21)
Engine: Start 6 - 14 V
while cranking 		Wiring,
Ignition/starter switch (S2/1),
Starter lock-out system.
8.0   Starter relay im pulse module

31
(1.31)
N3/4




39
(1.39)
Engine coolant
temperature >20°C

Turn ignition switch briefly to position 2.
6 - 14 V
(or approx. 5 second duration if engine does not start) 		Ignition switch,
Wiring,
Pulse module (N65).
Engine control module N3/4
9.0 0 0 2
0 0 3
0 0 4
0 0 5 		ECT sensor (B11/3)
Voltage

72
(2.28)
N3/4



80
(2.36)
Ignition: ON
C °    V
20   3.5
30   3.1
40   2.7
50   2.3
60   1.9
70   1.5
80   1.2
90   1.0
100   0.8

±5%
9.1 ,
Wiring,
Engine control module (N3/4).
9.1   Resistance (B11/3)
72
(2.28)
N3/4



80
(2.36)
Ignition: OFF
Unplug connector 2 on N3/4. 		C °    
20   2500
30   1700
40   1170
50   830
60   600
70   435
80   325
90   245
100   185

± 5% 		Wiring,
B11/3.
10.0 0 0 6
0 0 7
0 0 8 		IAT sensor (B17), (B2/5)
Voltage

72
(2.28)
N3/4



81
(2.37)
Ignition: ON °C   V
10   3.2
20   2.6
30   2.1
40   1.6
50   1.2
60   0.9

±5 %
10.1 ,
Engine control module (N3/4).
10.1   Resistance

72
(2.28)
N3/4



81
(2.37)
Ignition: OFF
Unplug connector 2 on N3/4.
C °   
10   9670
20   6060
30   3900
40   2600
50   1760
60   1220

±5 %
Wiring,
B17, B2/5
11.0 0 7 0
0 7 1 		TN-signal output
(engine rpm output signal)
Engine control module (N3/4)

32
(1.32)




32
(1.32)
N3/4 3)





N3/4 4)



18
(1.18)





18
(1.18)
Engine: Start or
Engine: at Idle 		Signal, see
Figure 1.





5 - 7.5 V 		Wiring,
CKP sensor (L5)
Engine control module (N3/4).
12.0 0 7 4
0 7 5 		Non-USA vehicles only.
Continue to next test step. 		           
12.1   Non-USA vehicles only.
Continue to next test step. 		           
13.0 0 2 3
0 2 4
0 2 5 		O2S 1 (before TWC) (G3/2)
O2S 1 signal
34
(1.34)
N3/4 3)4)




35
(1.35)
Engine: at Idle
and at operating temperature > 80 °C let engine run for a minimum of 2 minutes.
Oscillates
between
-0.2 and +1.0 V by more than
0.3
Figure 14 		Wiring,
O2S 1 (G3/2),
13.1 ,
14.0
13.1   Insulation, O2S 1 wire
35
(1.35)
N3/4



36
(1.36)
Ignition: OFF
Unplug connector 1 on N3/4.
>20 k Wiring.
14.0 0 2 9
0 3 0
0 3 1 		O2S 1 (before TWC) (G3/2)
O2S 1 heater
Control signal
32
(1.32)
N3/4



30
(1.30)
Engine: at Idle
and at operating temperature > 80 °C let engine run for a minimum of 2 minutes.
11 - 14 V
or voltage changes between
1 - 14 V 		Engine control module (N3/4),
14.1
14.1   Current draw

30
(1.30)
N3/4



39
(1.39)
Ignition: ON 0.6 - 3.4 A Wiring,
O2S 1 (G3/2).
15.0 0 2 6
0 2 7
0 2 8 		Perform both measurements simultaneously
O2S 2 (after TWC) (G3/1)
O2S 2 signal










Note to Test connection:
Connect second multimeter.

O2S 2 (after TWC) heater relay module (K35)
Control signal

24
(1.24)

















31
(1.31)
N3/4


















N3/4



25
(1.25)


















27
(1.27)
Start engine at engine coolant temperature
> 80°C.

Maintain an engine speed
of 2000 - 3000 rpm for
approx. 3 minutes until
O2S 2 (after TWC) heater
is switched on (see second
multimeter or HHT).

Accelerate briefly





O2S 2 (after TWC) heater not switched on

O2S 2 (after TWC) heater switched on
Note:
After the O2S 2 heater is switched on, the O2S 2 signal must change.
450 mV
constant
















Voltage
changes by
> 100 mV

Figure 14

11 - 14 V



< 1 V 		Wiring,
15.1 ,
16.0 ,
17.0 ,
O2S 2 (G3/1).
15.1 0 2 9
0 3 0
0 3 1 		Insulation, O2S 2 wire

25
(1.25)
N3/4



26
(1.26)
Ignition: OFF
Unplug connector 1 on N3/4. 		>20 k Wiring.
16.0 0 3 2
0 3 3
0 3 4 		O2S 2 (after TWC) (G3/1)
O2S 2 heater
Control signal

32
(1.32)
N3/4



41
(1.41)
Engine: at Idle
and at operating temperature > 80 °C let engine run for a minimum of 2 minutes.
11 - 14 V 16.1 ,
Engine control module (N3/4).
16.1   Current draw

41
(1.41)
N3/4



39
(1.39)
Ignition: ON 0.6 - 3.4 A Wiring,
O2S 2 (after TWC) heater relay module (K35)
O2S 2 (G3/1).
17.0 1 0 8
1 0 9 		O2S 2 (after TWC) heater relay module (K35)
Control signal

31
(1.31)
N3/4



27
(1.27)
Disconnect ECT sensor (B11/3) and simulate 2.5 k at sockets 1 and 2 with resistance substitution unit.
Engine: at Idle
11 - 14 V 17.1 ,
N3/4.
17.1   Current draw

33
(1.33)
N3/4



31
(1.31)
Ignition: ON 0.1 - 0.3 A Wiring,
K35.
18.0 0 3 7
0 3 8 		Injector (Y62y1)
Control and injection time



67
(2.23)


N3 / 4






39
(1.39)
ECT approx. 20 °C
at start

ECT approx. 80 °C
at idle
accelerate briefly 		Injection time:
approx. 8 ms


approx. 3 - 5 ms
approx. 17 ms
(see signals,
Figures 2 and 3)
18.1 ,
N3/4.

Further possible causes:
ECT sensor (B11/3),
IAT sensor (B17),
O2S 1 (G3/2).
18.1   Resistance

67
(2.23)
N3 / 4



39
(1.39)
Ignition: OFF
Connector 2 on engine control module unplugged. 		14 - 17 Wiring,
Y62y1.
19.0 0 3 9
0 4 0 		Injector (Y62y2)
Control and injection time



68
(2.24)


N3 / 4





39
(1.39)
ECT approx. 20 °C
at start

ECT approx. 80 °C
at idle
accelerate briefly 		Injection time:
approx. 8 ms


approx. 3 - 5 ms
approx. 17 ms
(see signals,
Figures 2 and 3)
19.1 ,
N3/4.

Further possible causes:
ECT sensor (B11/3),
IAT sensor (B17),
O2S 1 (G3/2).
19.1   Resistance

68
(2.24)
N3 / 4



39
(1.39)
Ignition: OFF
Connector 2 on engine control module unplugged. 		14 - 17 Wiring,
Y62y2.
20.0 0 4 1
0 4 2 		Injector (Y62y3)
Control and injection time



56
(2.12)


N3 / 4





39
(1.39)
ECT approx. 20 °C
at start

ECT approx. 80 °C
at idle
accelerate briefly 		Injection time:
approx. 8 ms


approx. 3 - 5 ms
approx. 17 ms
(see signals,
Figures 2 and 3)
20.1 ,
N3/4.

Further possible causes:
ECT sensor (B11/3),
IAT sensor (B17),
O2S 1 (G3/2).
20.1   Resistance

56
(2.12)
N3 / 4



39
(1.39)
Ignition: OFF
Connector 2 on engine control module unplugged. 		14 - 17 Wiring,
Y62y3.
21.0 0 4 3
0 4 4 		Injector (Y62y4)
Control and injection time



46
(2.2)


N3 / 4





39
(1.39)
ECT approx. 20 °C
at start

ECT approx. 80 °C
at idle
accelerate briefly 		Injection time:
approx. 8 ms


approx. 3 - 5 ms
approx. 17 ms
(see signals,
Figures 2 and 3)
21.1 ,
N3/4.

Further possible causes:
ECT sensor (B11/3),
IAT sensor (B17),
O2S 1 (G3/2).
21.1   Resistance

46
(2.2)
N3 / 4



39
(1.39)
Ignition: OFF
Connector 2 on engine control module unplugged. 		14 - 17 Wiring,
Y62y4.
22.0 0 6 8
0 6 9 		Non-USA vehicles only.
Continue to next test step. 		 

 
       
22.1   Non-USA vehicles only.
Continue to next test step. 		           
23.0 0 7 7
0 7 8 		Non-USA vehicles only.
Continue to next test step. 		           
23.1   Non-USA vehicles only.
Continue to next test step. 		           
24.0 0 7 2
0 7 3 		Vehicle speed signal (VSS)
ABS control module

32
(1.32)
N3/4



8
(1.8)
Raise rear of vehicle.
Ignition: ON
Turn one rear wheel by hand. 		>3 V Wire from ABS control module to engine control module (N3/4),
Rear axle VSS sensor (L6)
(Test, see SMS, Brakes - ABS).
25.0 0 8 6
0 8 7 		Purge control valve (Y58/1)
Control signal

43
(1.43)
N3/4



39
(1.39)
Engine: at Idle
and at operating temperature. 		After approx. 1 min, purge con-trol valve (Y58/1, Figure 5) must cycle noticeably (signal, see Figure 4).
25.1 ,
26.0 ,
N3/4.
25.1 0 8 6
0 8 7 		Current draw

32
(1.32)
N3/4



43
(1.43)
Ignition: ON 0.2 - 0.3 A Fuse,
Wiring,
Y58/1.
26.0
  		Purge control valve (Y58/1)

Vacuum control
 

 

 
Note to test connection:
Connect vacuum tester to Y58/1 (Figure 5), connection (A).

Engine: at Idle
and at operating temperature.





After approx. 1 minute,
> 400 mbar 		Vacuum lines,
Y58/1.
27.0 0 8 9
0 9 0 		Adjustable camshaft timing solenoid (Y49)
Current draw
1
Y49

2
Note to test connection:
Connect test cable
(102 589 04 63 00) to solenoid.
Engine: at Idle and accelerate engine briefly.




1 - 1.5 A,
28.0 ,
Engine control module (N3/4).
27.1   Non-USA vehicles only.
Continue to next step.
 

 
       
27.2   Non-USA vehicles only.
Continue to next step.
 

 

 

  		   
27.3   Non-USA vehicles only.
Continue to next step. 		           
28.0   Adjustable camshaft timing solenoid
Mechanical operation

45
(2.1)
N3/4



66
(2.22)
Engine: at Idle
Bridge socket box sockets for maximum of 10 seconds. 		Engine runs unevenly or stalls. Mechanical camshaft adjustment
(see SMS, Engine 111,
Job No. 05-2160).
29.0 0 8 8 Upshift delay switchover valve (Y3/3)
Current draw

42
(1.42)
N3 / 4



39
(1.39)
Ignition: ON 0.4 - 0.6 A Wiring,
Y3/3,
30.0.
30.0   Pneumatic upshift delay
Vacuum control and sealing

42
(1.42)
N3 / 4



39
(1.39)
Note to test connection:
Connect vacuum tester to upshift delay switchover valve (Y3/3) according to Figure 6.

Engine: at Idle






> 400 mbar 		Vacuum lines,
Y3/3.
31.0   A/C compressor engagement signal

32
(1.32)
N3/4



11
(1.11)
Engine: at Idle
A/C system: ON 		11 - 14 V Wiring,
A/C pushbutton control
module (N22).
32.0   Cruise control ON recognition

32
(1.32)
N3/4



22
(1.22)
Test condition 5)

Cruise control switch: Accelerate

OFF
or apply brake pedal


11 - 14 V

<1 V
Wiring,
Cruise control switch (S40).
33.0   Non-USA vehicles only.
Continue to next test step. 		           
34.0   Non-USA vehicles only.
Continue to next test step. 		           
35.0   Transmission range 2/3 recognition

5
(1.5)
N3/4



23
(1.23)
Ignition: OFF
Unplug connector 1 on
engine control
module (N3/4).
Transmission range:
D
2 - 3




>20 k
<1 		Wiring,
Starter lock-out/backup lamp
switch (S16/1).
36.0 1 0 2
1 0 3 		Non-USA vehicles only.
Continue to next test step. 		           
37.0   Non-USA vehicles only.
Continue to next test step. 		           
37.1   Non-USA vehicles only.
Continue to next test step. 		           
38.0 0 8 5 AIR pump switchover valve (Y32) and/or AIR relay
module (K17)

32
(1.32)
N3/4



59
(2.15)
Disconnect ECT sensor (B11/3) and simulate 2.5 k at sockets 1 and 2 with resistance substitution unit,
Engine: at Idle
11 - 14 V
for approx. 2 minutes and AIR pump runs. 		N3/4.
38.1   Current draw

59
(2.15)
N3 / 4



39
(1.39)
Ignition: ON 0.4 - 0.7 A Wires,
Y32,
K17.
39.0 0 9 1
0 9 2 		EGR switchover
valve (Y27)
Vacuum control

69
(2.25)
N3 / 4



39
(1.39)
Engine: at Idle
Engine coolant
temperature > 60 °C
Briefly apply full throttle.
11 - 14V 39.1 ,
N3/4,
40.0 - 41.0
39.1   Current draw

32
(1.32)
N3 / 4



69
(2.25)
Ignition: ON 0.3-0.5 A Fuse,
Wiring,
Y27.
40.0   EGR switchover
valve (Y27)
Vacuum control 		      Note to test connection:
Connect vacuum tester to the EGR valve (Figure 7).

Engine control module (N3/4) plugged in.
Engine: Start and run at
> 3000 rpm.






> 400 mbar 		Vacuum lines,
EGR valve,
Y27.
41.0   EGR valve
Mechanical test 		      Note to test connection:
Connect vacuum tester to the EGR valve (Figure 11).

Engine: at Idle
Apply 500 mbar vacuum with vacuum tester.

Engine: OFF
Apply 500 mbar vacuum with vacuum tester and pull off vacuum line.





Engine runs unevenly


EGR valve closes audibly 		EGR valve.
42.0 0 9 8
0 9 9
1 0 0
1 1 6
1 5 2 		Up to end of M.Y. 1995

Serial data bus (CAN)





As of M.Y. 1996
With DAS, stage 2, 2b, 3
L







L
N59/1







N3/4

H







H
Ignition: OFF

Unplug diagnostic module
(N59/1) and measure
resistance directly at
connector for diagnostic
module (Figure 8).

Unplug connector 1 from
test cable on engine
control module and test
with ohmmeter directly on
connector 1 of engine
wiring harness (Figure 10).
55 - 65







115 - 125 		43.0 ,
Data line.






42.1 ,
Data line.
42.1 1 1 6 CAN element in RCL control module (N54)
Vehicles as of M.Y. 96
Resistance
L
N54

H
Ignition: OFF
Remove RCL control module (N54) and measure with ohmmeter directly on N54 (Figure 11).
115 - 125 		N54.
43.0 0 9 7 CAN element in engine control module (N3/4)
Resistance
L
N3/4

H
Ignition: OFF
Unplug connector 1 on N3/4 and measure resistance directly at engine control module (Figure 12) 		55 - 65 N3/4.
44.0   O2S 1 (before TWC) (G3/2)
O2S signal for Diagnostic Module (OBD II) (N59/1)


34
(1.34)

N3/4



15
(1.15)
Engine: at Idle
and at operating temperature > 80 °C. Allow engine to run for a minimum of 2 minutes.
Oscillates in range between -0.2 and
+1.0 V by more than 0.3 V 		Wiring,
N3/4.
45.0   O2S 2 (after TWC) (G3/1)
O2S signal for Diagnostic Module (OBD II) (N59/1)

24
(1.24)
N3/4



16
(1.16)
At operating temperature > 80 °C start engine

and run at 2000 - 3000 rpm for a minimum of 3 minutes.

Accelerate briefly.
450 mV
constant.

Voltage
fluctuates.


Voltage fluctuates by >100 mV
Wiring,
N3/4.
46.0   CMP sensor (L5/1)
Signal for Diagnostic Module (OBD II) (N59/1)

32
(1.32)
N3/4



17
(1.17)
Engine: at Idle 9.5 - 10.5 V Wiring,
N3/4.
47.0 1 1 8 Non-USA vehicles only. Continue to next test step.          
 
48.0 1 1 9 Non-USA vehicles only. Continue to next test step.
 

 

 

  		 
 
48.1 1 2 3
1 2 4 		Non-USA vehicles only. Continue to next test step.
 

 

 
   
 
49.0 1 2 3
1 2 4 		Non-USA vehicles only. Continue to next test step.            
50.0   Non-USA vehicles only. Continue to next test step.            
51.0 1 5 3
1 5 4 		Non-USA vehicles only. Continue to next test step.            
2) Voltage increases with increasing rpm.
3) Test with oscilloscope.
4) Test with multimeter only if oscilloscope is not available.
5) Drive vehicle above 25 mph (40 km/h) on dynamometer.





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