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Diagnostic Manual, Engines, Volume 4

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LOCATION:    9.6 ME - SFI (ME1.0)   >  23 Electrical Test Program - Test


Electrical Test Program - Test

Test scope Test connection Test condition Nominal value Possible cause/Remedy
1.0 P 0 5 6 0
P 1 5 8 7 		Engine control module
(ME-SFI) (N3/11 or N3/12)
Voltage supply
Circuit 30


26
(1.26)
N3/11
N3/12




35
(1.35)
Ignition: ON
11 - 14 V
1.1


1.1   Ground wire



26
(1.26)

39
(1.39)
N3/11
N3/12







X11/4
2


2
Ignition: ON 11 - 14 V Wiring,
Model 129:
Ground (W27), module box bracket.
Model 140:
Output ground (W15), right footwell.
1.2
1.2   Voltage supply
Circuit 30

X11/4
1
N3/11
N3/12




35
(1.35)
Ignition: ON 11 - 14 V Wiring,
Base moduel (N16/1) or fuse on base module.
2.0 P 0 5 6 0
P 1 5 8 7 		Engine control module
(ME-SFI) (N3/11 or N3/12)
Voltage supply
Circuit 87L



38
(1.38)
N3/11
N3/12




24
(1.24)
Ignition: ON 11 - 14 V 2.1
2.1   Electronics ground


38
(1.38)
N3/11
N3/12



X11/4
2
Ignition: ON 11 - 14 V Wiring,
Model 129, 140:
Electronics ground (W15/1), right footwell.
2.2
2.2   Voltage supply
Circuit 87L

X11/4
1
N3/11
N3/12




24
(1.24)
Ignition: ON


Ignition: OFF 		11 - 14 V


< 1 V
Wiring,
Base module (N16/1) or fuse on base module,
Ignition/starter switch (S2/1)
3.0 P 0 5 6 0
P 1 5 8 7 		Engine control module
(ME-SFI) (N3/11 or N3/12)
Voltage supply
Circuit 87M1e


39
(1.39)
N3/11
N3/12




36
(1.36)
Ignition: ON


Ignition: OFF
11 - 14 V


< 1 V 		Wiring.
4.0 P 0 1 0 0
P 1 1 4 6 		Left hot film MAF
sensor (B2/6)
Right hot film MAF
sensor (B2/7)
Voltage at hot film


68
(2.68)
N3/11
N3/12



67
(2.67)
Ignition: ON
Engine: at Idle
Engine coolant
temperature >70°C

0.6 - 0.9 V 1) 		Wiring
4.1 ,
Air intake system leak,
B2/6 or B2/7
4.1   Ground wire for hot film MAF sensor (B2/6 or B2/7)


38
(1.38)
N3/11
N3/12




67
(2.67)
Ignition: OFF
Disconnect MAF sensor (B2/6 or B2/7) connector. Bridge sockets 1 and 4
< 1 Ground wire.
5.0 P 0 1 0 5
P 1 1 4 9 		Left pressure sensor (B28/1)
Right pressure sensor (B28/2)
Sender signal
(only )


87
(2.87)
N3/11
N3/12




65
(2.65)
Connect vacuum tester to pressure sensor (B28/1 or B28/2) using Y-fitting (see 21 )
Ignition: ON

Engine: at Idle




> 3.5 V

< 2 V and pressure climbs to > 500 mbar.
Vacuum line,
Wiring,
5.1
B28/1 or B28/2
5.1   Pressure sensor (B28/1 or B28/2)
Voltage supply



87
(2.87)
N3/11
N3/12




88
(2.88)
Ignition: ON
4.7 - 5.3 V N3/11 or N3/12
6.0   Right engine control module (N3/12) only

FP relay module (K27)
Activation

24
(1.24)
N3/12



25
(1.25)
Ignition: ON


Engine: Start 		11 - 14 V for approx. 1 sec.

11 - 14 V during cranking and while engine runs.
6.1 ,
N3/12
6.1   Current draw (K27)

26
(1.26)
N3/12



24
(1.24)
Ignition: ON 0.1 - 0.3 A Wiring,
K27
7.0 P 0 1 1 5
P 1 1 4 7 		Left ECT sensor (B11/9)
Right ECT sensor (B11/10)
Voltage


87
(2.87)
N3/11
N3/12




76
(2.76)
Ignition: ON °C
V 7.1 ,
N3/11 or N3/12
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 %
7.1   Resistance


87
(2.87)
N3/11
N3/12




76
(2.76)
Ignition: OFF
Disconnect connector 2
on engine control
module (N3/11 or N3/12). 		°C
Wiring,
7.2
20 2500
30 1700
40 1170
50 830
60 600
70 435
80 325
90 245
100 185
±5 %
7.2   ECT sensor (B11/9 or B11/10)
Resistance

1
B11/9
B11/10



4
Disconnect connector on ECT sensor (B11/9 or B11/10). Nominal value, see 7.1 B11/9 or B11/10

8.0 P 0 1 1 0
P 1 1 4 8 		Left IAT sensor (B17/5)
Right IAT sensor (B17/6)
Voltage


87
(2.87)
N3/11
N3/12




64
(2.64)
Ignition: ON °C
V 8.1 ,
N3/11 or N3/12
10 3.2
20 2.6
30 2.1
40 1.6
50 1.2
60 0.9
70 0.7
±5 %
8.1   Resistance (B17/5 or B17/6)


87
(2.87)
N3/11
N3/12




64
(2.64)
Ignition: OFF
Disconnect connector 2
on engine control
module (N3/11 or N3/12). 		°C
Wiring,
8.2
10 9670
20 6060
30 3900
40 2600
50 1760
60 1220
70 860
±5 %
8.2   IAT sensor (B17/5 or B17/6) Resistance

1
B17/5
B17/6



2
Disconnect connector from IAT sensor (B17/5 or B17/6). Nominal value, see 8.1
B17/5 or B17/6
9.0   Right engine control module (N3/12) only
TN-signal output

38
(1.38)




38
(1.38)
N3/12




N3/12



56
(1.56)




56
(1.56)
Test with Oscilloscope:
Engine: Start or
Engine: at Idle




Test with multimeter:
(only if oscilloscope not available) 		Signal: see
Figure 2.





5 - 7.5 V 		Wiring,
N3/12
10.0 P 0 1 3 0
P 0 1 3 3
P 0 1 4 0
P 0 1 5 0
P 0 1 5 3
P 0 1 6 0 		Left O2S 1
(before TWC) (G3/3)
Right O2S 1
(before TWC) (G3/4)
O2S signal


40
(1.40)
N3/11
N3/12




41
(1.41)
ECT > 80 ° C, run engine at idle for at least two minutes.
fluctuates from
- 0.2 V to +
1.0 V, by more
than 0.3 V 		Wiring,
G3/3 or G3/4,
11.0
11.0 P 0 1 3 5
P 0 1 5 5 		Left O2S 1
(before TWC) (G3/3)
Right O2S 1
(before TWC) (G3/4)
O2S heater activation


13
(1.13)
N3/11
N3/12




25
(1.25)
ECT > 80 ° C, run engine at idle for at least two minutes. 11 - 14 V 11.1 ,
N3/11 or N3/12
11.1   O2S 1 (G3/3 or G3/4)
Current draw


26
(1.26)
N3/11
N3/12




13
(1.13)
Ignition: ON 0.6 - 3.4 A Wiring,
G3/3 or G3/4
12.0. P 0 1 3 6
P 0 1 5 6

Left O2S 2
(afterTWC) (G3/5)
Right O2S 2
(afterTWC) (G3/6)
O2S signal
(only )


40
(1.40)
N3/11
N3/12




42
(1.42)
ECT > 80° C,
Engine: Start

Raise and hold engine speed at 2000 - 3000 rpm for approx. two minutes until O2S 2 heater turns on (see HHT).
The range of 450mV to 550mV, must be attained or not attained within 1 minute.

Wiring,
13.0
13.0 P 0 1 4 1
P 0 1 6 1 		Left O2S 2
(after TWC) (G3/5)
Right O2S 2
(after TWC) (G3/6)
O2S heater activation
(only )



12
(1.12)
N3/11
N3/12




25
(1.25)
Engine: at Idle
ECT > 80° C, run engine at idle for at least two minutes.

11 - 14 V 13.1 ,
N3/11 or N3/12
13.1   O2S 2 (G3/5 or G3/6)
Current draw


26
(1.26)
N3/11
N3/12




12
(1.12)
Ignition: ON 0.6 - 3.4 A Wiring,
G3/5 or G3/6
14.0 P 0 2 0 1
P 0 2 0 7 		Injector (Y64y1, Y63y7)
Activation and injection time


72
(2.72)
N3/11
N3/12




25
(1.25)
ECT approx. 20° C
at start:

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


approx. 3 - 5 ms
approx. 14 ms

(signals see Figures 2 and 3)
14.1 ,
N3/11 or N3/12,

Further possibilities:
ECT sensor (B11/9 or B11/10),
IAT sensor (B17/5 or B17/6),
O2S 1 (G3/3 or G3/4).
14.1   Resistance


72
(2.72)
N3/11
N3/12




25
(1.25)
Ignition: OFF
14 - 17
Wiring,
Y64y1, Y63y7
15.0 P 0 2 0 2
P 0 2 0 8 		Injector (Y64y2, Y63y8)
Activation and injection time


70
(2.70)
N3/11
N3/12




25
(1.25)
ECT approx. 20° C
at start:

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


approx. 3 - 5 ms
approx. 14 ms

(signals see Figures 2 and 3)
15.1 ,
N3/11 or N3/12,

Further possibilities:
ECT sensor (B11/9 or B11/10),
IAT sensor (B17/5 or B17/6),
O2S 1 (G3/3 or G3/4).
15.1   Resistance


70
(2.70)
N3/11
N3/12




25
(1.25)
Ignition: OFF
14 - 17
Wiring,
Y64y2, Y63y8
16.0 P 0 2 0 3
P 0 2 0 9 		Injector (Y64y3, Y63y9)
Activation and injection time


93
(2.93)
N3/11
N3/12




25
(1.25)
ECT approx. 20° C
at start:

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


approx. 3 - 5 ms
approx. 14 ms

(signals see Figures 2 and 3)
16.1 ,
N3/11 or N3/12,

Further possibilities:
ECT sensor (B11/9 or B11/10),
IAT sensor (B17/5 or B17/6),
O2S 1 (G3/3 or G3/4).
16.1   Resistance


93
(2.93)
N3/11
N3/12




25
(1.25)
Ignition: OFF
14 - 17
Wiring,
Y64y3, Y63y9
17.0 P 0 2 0 4
P 0 2 1 0 		Injector (Y64y4, Y63y10)
Activation and injection time


69
(2.69)
N3/11
N3/12




25
(1.25)
ECT approx. 20° C
at start:

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


approx. 3 - 5 ms
approx. 14 ms

(signals: see Figures 2 and 3).
17.1 ,
N3/11 or N3/12

Further possibilities:
ECT sensor (B11/9 or B11/10),
IAT sensor (B17/5 or B17/6),
O2S 1 (G3/3 or G3/4).
17.1   Resistance (Y64y4 or Y63y10)


69
(2.69)
N3/11
N3/12




25
(1.25)
Ignition: OFF
14 - 17
Wiring,
Y64y4 or Y63y10
18.0 P 0 2 0 5
P 0 2 1 1 		Injector (Y64y5, Y63y11)
Activation and injection time


71
(2.71)
N3/11
N3/12




25
(1.25)
ECT approx. 20° C
at start:

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


approx. 3 - 5 ms
approx. 14 ms

(signals: see Figures 2 and 3).
18.1 ,
N3/11 or N3/12

Further possibilities:
ECT sensor (B11/9 or B11/10),
IAT sensor (B17/5 or B17/6),
O2S 1 (G3/3 or G3/4).
18.1   Resistance (Y64y5 or Y63y11)


71
(2.71)
N3/11
N3/12




25
(1.25)
Ignition: OFF
14 - 17
Wiring,
Y64y5, Y63y11
19.0 P 0 2 0 6
P 0 2 1 2 		Injector (Y64y6, Y63y12)
Activation and injection time


82
(2.82)
N3/11
N3/12




25
(1.25)
ECT approx. 20° C
at start:

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


approx. 3 - 5 ms
approx. 14 ms

(see Figures 2 and 3)
19.1 ,
N3/11 or N3/12,

Further possibilities:
ECT sensor (B11/9 or B11/10),
IAT sensor (B17/5 or B17/6),
O2S 2 (G3/3 or G3/4).
19.1   Resistance (Y64y6 or Y63y12)


82
(2.82)
N3/11
N3/12




25
(1.25)
Ignition: OFF
14 - 17
Wiring,
Y64y6, Y63y12
20.0 P 0 4 1 0
P 1 4 5 3
P 1 4 6 3 		Right engine control module (N3/12)

AIR relay module (K17)
Activation

57
(1.57)
N3/12




25
(1.25)
Disconnect right ECT sensor (B11/10) connector. Simulate
2.5 k resistance at sockets 1 and 4 with resistance substitution unit.
Engine: at Idle
11 - 14 V
for approx. two minutes and AIR pump runs. 		20.1 ,
N3/12
20.1   Current draw (K17)

38
(1.38)
N3/12




57
(1.57)
Ignition: ON 0.1 - 0.3 A Wiring,
K17
21.0 P 0 4 1 0
P 1 4 2 0
P 1 4 6 3 		Right engine control module (N3/12)

AIR pump switchover valve (Y32)
Activation

114
(2.114)
N3/12




25
(1.25)
Disconnect right ECT sensor (B11/10) connector. Simulate
2.5 k resistance at sockets 1 and 4 with resistance substitution unit.
Engine: at Idle
11 - 14 V
for approx. two minutes and AIR pump runs. 		21.1 ,
N3/12
21.1   Current draw (Y32)

38
(1.38)
N3/12




114
(2.114)
Ignition: ON 0.3 - 0.5 A Wiring,
Y32
22.0 P 1 5 1 9
P 1 5 2 2
P 1 5 2 5
P 1 5 3 3 		Left adjustable camshaft timing solenoid (Y49/1)
Right adjustable camshaft timing solenoid (Y49/2)
Current draw

1
Y49/1
Y49/2



2

Connect test cable
(102 589 04 63 00) to solenoid.

Engine: Start
and increase engine speed to 3000 rpm.





approx. 1.0 A
22.1 ,
23.0 ,
N3/11 or N3/12.
22.1   Resistance Y49/1 or Y49/2

1
Y49/1
Y49/2



2
Ignition: OFF
Unplug connector on left or right camshaft timing solenoid (Y49/1 or Y49/2).
7 - 12 Y49/1 or Y49/2
23.0 P 1 5 1 9
P 1 5 2 2
P 1 5 2 5
P 1 5 3 3 		Left adjustable camshaft timing solenoid (Y49/1)
Right adjustable camshaft timing solenoid (Y49/2)
Mechanical function

113
(2.113)
N3/11
N3/12





38
(1.38)
Engine: at Idle


Bridge sockets on socket box for a maximum of 10 seconds only.
Engine runs rough after approx. 5 seconds. Check function of camshaft adjuster (see SMS, Engine 120, Job No. 05-2160).
24.0 P 0 4 4 0
P 0 4 4 1
P 0 4 4 6
P 0 4 4 3
P 1 4 4 3
P 1 4 9 0 		Left purge control
valve (Y58/2)
Right purge control
valve (Y58/3)
Activation


10
(1.10)
N3/11
N3/12




25
(1.25)
Engine: at Idle
and at operating temperature. 		After approx. 1 minute, purge control valve (Y58/2 or Y58/3) must noticeably cycle Signal (see Figure 4).
24.1 ,
25.0 ,
N3/11 or N3/12
24.1   Current draw (y58/2 or Y58/3)


38
(1.38)
N3/11
N3/12




10
(1.10)
Ignition: ON 0.1 - 0.3 A Wiring,
Y58/2 or Y58/3
25.0 P 0 4 4 0
P 0 4 4 1
P 1 4 4 3
Purge control
valve (Y58/2 or Y58/3)
Vacuum control 		 
Connect vacuum tester to purge control valve (Y58/2 or Y58/3) connector (A) (see 21 ).

Engine at operating temperature and at idle, increase engine speed to maximum 3000 rpm









After approx. 1 minute,
> 50 mbar and needle oscillates.
Vacuum line,
Y58/2 or Y58/3
26.0 P 0 4 4 0
P 0 4 4 2
P 0 4 4 5
P 0 4 4 6 		Only , Model 140 and 129 as of 09/97
Right engine control module (N3/12)

Purge system
Leaks

Activated charcoal canister shut-off valve (Y58/4) activated








26
(1.26)






N3/12










34
(1.34)
Disconnect purge line
(A) to charcoal canister
on right purge control
valve (Y58/3, left side of
engine compartment).
Connect vacuum tester
to purge line
(see 21 ).
Ignition: ON

Apply approx. 25 mbar of
vacuum.
















After approx. 1 minute,
< 5 mbar vacuum loss.
Fuel tank cap,

Purge line to charcoal canister,

Purge line from charcoal canister
to Y58/4,

Activated charcoal canister,

Y58/4,

Fuel tank pressure
sensor (B4/3)

27.0 P 0 4 4 6 Only , Model 140 and 129 as of 09/97
Right engine control module (N3/12)

Activated charcoal canister shut-off valve (Y58/4)
Current draw


38
(1.38)
N3/12




34
(1.34)
Ignition: ON 0.5 - 0.9 A Fuses,
Wiring,
Y58/4
28.0 P 0 4 4 6
P 0 4 5 0
P 0 4 5 5 		Only , Model 140 and 129 as of 09/97
Right engine control module (N3/12)

Fuel tank pressure
sensor (B4/3)
Sender signal


Activated charcoal canister shut-off valve (Y58/4) activated


53
(1.53)






26
(1.26)
N3/12







N3/12



51
(1.51)






34
(1.34)
Disconnect purge line (A) to charcoal canister on right purge control valve (Y58/3, left side of engine compartment). Connect vacuum tester to purge line (see 21 ).

Ignition: ON

Apply approx. 25 mbar of vacuum.













> 3 V

< 2.5 V
28.1 ,
Wiring,
Vacuum line,
Activated charcoal canister plugged,
B4/3
28.1   Only
Fuel tank pressure
sensor (B4/3)
Voltage supply

53
(1.53)
N3/12




44
(1.44)
Ignition: ON 4.7 - 5.3 V N3/12
29.0 P 0 4 5 0
Only , Model 129 up to 09/97
Right engine control module (N3/12)

Purge monitoring pressure
sensor (B4/4)
Sender signal

53
(1.53)
N3/12




51
(1.51)
Disconnect purge line
(A) to charcoal canister
on purge monitoring
pressure sensor (B4/4).
Connect vacuum tester
to purge monitoring
pressure sensor
(see 21 ).

Ignition: ON


Apply approx. 300 mbar
of vacuum.
















> 3.5 V


< 3 V
Wiring,
29.1 ,
B4/4
29.1   Purge monitoring pressure
sensor (B4/4)
Voltage supply

53
(1.53)
N3/12




44
(1.44)
Ignition: ON 4.7 - 5.3 V N3/12
30.0 P 0 6 0 0
P 1 5 7 0
P 1 5 8 8
P 1 6 4 1
P 1 7 4 7 		CAN data bus




60
(1.60)
N3/11
N3/12




61
(1.61)
Ignition: OFF

Disconnect connector 1 from test cable and measure resistance directly at connector 1 (interior) using an ohmmeter. Wire connections: see 22 .
75 - 85 30.1 ,
30.2 ,
Data line.
30.1   CAN element in RCL control module (N54)
Resistance





L
N54
N54/1





H
Ignition: OFF
Disconnect control module (N54 or N54/1) and test directly at pins (Figure 5).
115 - 125 N54 or N54/1
30.2   CAN element in engine control module (N3/11 or N3/12)
Resistance


60
N3/11
N3/12





61
Ignition: OFF
Disconnect connector 1 (interior) from engine control module (N3/11 or N3/12) and test directly at pins.
235 - 245 N3/11 or N3/12
31.0 P 1 1 6 3 Right engine control module (N3/12)
Oil level switch (S43)

32
(1.32)
N3/12



25
(1.25)
Ignition: ON

Oil level okay.
Oil level low.


11 - 14 V
< 1 V 		Wiring,
S43
32.0 P 1 1 7 7 Oil temperature
sensor (B1) to ME control module (N3/12)
Voltage

87
(2.87)
N3/12





81
(2.81)
Ignition: ON
°C V 32.1
N3/12
10 3.9
20 3.5
30 3.1
40 2.7
50 2.3
60 1.9
70 1.5
80 1.2
±5 %
32.1   Oil temperature
sensor (B1)
Resistance

87
(2.87)


N3/12





81
(2.81)
Ignition: ON
°C Wiring,
B1
10 3807
20 2510
30 1722
40 1195
50 854
60 614
70 450
80 335
±5 %
33.0   Fuel consumption signal
up to 05/96

25
(1.25)
N3/12




58
(1.58)
Engine: idle, then briefly apply throttle.


>0.5 V Wiring,
N3/12
34.0   Diagnosis line
Activation


26
(1.26)
N3/11
N3/12




55
(1.55)
Ignition: ON


11 - 14 V Wiring,
N3/11 or N3/12
35.0   Only on left engine control module (N3/11)

Coding

45
(1.45)
N3/11



25
(1.25)
Ignition: ON


11 - 14 V Wiring.
36.0 P 1 6 0 5 Only on right engine control module (N3/12) until 05/96 (eliminated as of 06/96)
Body acceleration
sensor (B24/7)
Sensor signal in static state




Sensor signal in dynamic state







53
(1.53)




53
(1.53)




N3/12




N3/12







48
(1.48)




48
(1.48)






Ignition: ON




Vigorously move left front corner of vehicle by hand.






2.35 - 2.65 V




> 5 mV~

Value changes with movement of vehicle.
Wiring,
36.1 ,
B24/7
36.1   Voltage supply (B24/7)
53
(1.53)
N3/12

44
(1.44)
Ignition: ON 4.7 - 5.3 V N3/12
37.0 P 1 4 3 7
P 1 4 4 4 		Not applicable to U.S.A. version vehicles  
     
37.1   Not applicable to U.S.A. version vehicles  
     
38.0   Only model 140 on right engine control module (N3/12) until 05/96 (as of 06/96 via CAN)
(only )
Fuel tank cap open signal




23
(1.23)



N3/12








25
(1.25)
Engine: at Idle

Tank cap open

Tank cap closed
after approx. 18 minutes

11 - 14 V


< 1 V
Leak in purge system, 26.0
39.0   Only on right engine control module (N3/12) until 05/96 (as of 06/96 via CAN)
(only )
"CHECK ENGINE"
MIL (A1e26)





11
(1.11)



N3/12







25
(1.25)
Ignition: ON 11 - 14 V N3/12
40.0   Engine control module (ME-SFI) coding
Bridge


73
(2.73)
N3/11
N3/12




96
(2.96)
Ignition: OFF < 1 Wiring.
41.0   Only model 129 on right engine control module (N3/12) (as of 06/98)

Starter relay module (K38/1)
Activation




104
(2.104)



N3/12







25
(1.25)
Starter switch in
position 3 (start position):
Crank briefly:


11 - 14 V
or if engine does not start for approx. 5 seconds. 		41.1 ,
N3/12
41.1   Starter signal, circuit 50

38
(1.38)
N3/12



14
(1.14)
Ignition: Start engine 11 - 14 V
during the start sequence. 		Wiring,
Ignition/starter switch
1) Voltage increases with increasing rpm.




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