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Diagnostic Manual, Chassis and Drivetrain,
Volume 2

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LOCATION:    5.2 Acceleration Slip Regulation (ASR)   >   23 Electrical Test Program - Test


Electrical Test Program - Test

Test step
DTC		   Test scope
Test connection
Test condition
Nominal value
Possible cause/Remedy
1.0 ABS/ASR control
module (N30/1)
Voltage supply
Circuit 87



32 (2.32)

25
(2.25)

40 (2.40)
N30/1










68 (1.27)

68 (1.27)

68 (1.27)
 Ignition: ON 11- 14 V 1.1
1.1   Voltage supply from
base module (BM) (N16/1)


W16
W16/1
W27



N30/1

68 (1.27)

Ignition: ON

11 - 14 V		 Fuse (F1) in N16/1,
1.1 or 1.2 23,
Wiring,
1.2.
1.2   Ground wire



W27

W16

W16





W27


W27


W27




W16/1


W16/1



W16/1

Model 124




Model 129






Model 140






N30/1

32 (1.32) 25 (2.25) 40 (2.40)




32
(1.32)

25
(2.25)

40 (2.40)



32 (1.32)


25 (2.25)

40
(2.40)

Ignition: OFF < 1 Wiring,

Model 124
Ground (W16),
Ground (W27).





Model 129
Ground (W27).






Model 140
Ground (W16/1).
2.0   ABS MIL (A1e17)

 

40 (1.35)

N30/1



 

76 (2.40)



Ignition: ON


Engine: at Idle


< 2 V
A1e17: ON

10 - 14 V
A1e17: OFF


A1e17,
2.1

12,
Wiring,
N30/1.
2.1   Diode in ABS/ASR hydraulic unit, solenoid valve
relay (A7/3k1)

--

Ignition: OFF
Disconnect N30/1 from contact box.
Ignition: ON

Engine: at Idle







A1e17: ON

A1e17: ON

 Wiring,
A7/3k1.
3.0   ASR MIL (A1e22)

 

40 (2.40)

N30/1



 

76 (1.29)



Ignition: ON


Engine: at Idle

< 2 V
A1e22: ON

10 - 14 V
A1e22: OFF


A1e22,
3.1

12,
Wiring,
N30/1.
3.1   Diode in ABS/ASR hydraulic unit, solenoid valve
relay (A7/3k1)

--

Ignition: OFF
Disconnect N30/1 from contact box.
Ignition: ON

Engine: at Idle





A1e22: ON

A1e22: ON
Wiring,
A7/3k1.
4.0   ASR warning lamp (A1e21)

 

78 (1.37)

N30/1



 

68 (1.27)



Ignition: ON


Engine: at Idle


A1e21: ON
10 - 14 V

A1e21: OFF
< 2 V
Wiring,
A1e21.
5.0   Diagnosis output

 

40 (2.40)

N30/1


 

57
(1.16)

Ignition: ON


10 - 14 V		 Wiring,
N30/1.
6.0   Circuit 61e voltage

 

40 (2.40)

N30/1


 

66 (1.25)

Ignition: ON

Engine: at Idle


< 1 V

11 - 14 V		 Wiring,
Generator (G2).
7.0 ABS/ASR hydraulic unit, solenoid valve relay (A7/3k1)
Control


Monitoring

 

27 (2.27)






40 (2.40)

40
(2.40)

40
(2.40)
N30/1





N30/1







 

7 (2.7)






1 (2.1)

21
(2.21)

22 (2.22)

 Ignition: ON

10 - 14 V





11 - 14 V		 12,
7.1.
7.1   Voltage supply

 

40 (2.40)
N30/1


 

7 (2.7)

Ignition: ON

11 - 14 V		 Wiring,
1.0,
N30/1,
7.2.
7.2   Coil resistance

 

27 (2.27)

N30/1



 

7
(2.7)

Ignition: OFF
Disconnect N30/1 from contact box.

40 - 80 		Wiring,
A7/3k1,
7.3
7.3   Working contact


W14
(2.27)




N30/1

7 (2.7)
Ignition: OFF
Disconnect N30/1 from contact box.

< 12 		Wiring,
A7/3k1.
8.0 ABS/ASR hydraulic unit, high-pressure/return pump
relay (A7/3k2)
Voltage supply

 

40 (2.40)

N30/1



 

7 (2.7)



Ignition: ON

11 - 14 V		 Wiring,
8.1.
8.1   Coil resistance

 

28 (2.28)

N30/1



 

7 (2.7)

Ignition: OFF
Disconnect N30/1 from contact box.

40 - 80 		Wiring,
A7/3k2.
9.0

Model 124.036 (02/93 ), 129.076, 140.04/05/07
Master brake cylinder switchover valve (Y61)
Internal resistance

 

1
(2.1)

N30/1


 

19 (2.19)

 Ignition: OFF
Disconnect N30/1 from contact box.

7 - 8 		Wiring,
Y61.
10.0 Stop lamp switch (S9/1)
N.O. contact



N.C. contact

 

40 (2.40)





40 (2.40)

N30/1




N30/1



 

49
(1.8)




45 (1.4)

Ignition: ON

Brake pedal not depressed.

Depress brake pedal.


Brake pedal not depressed.

Depress brake pedal.





< 1 V

11 - 14 V




11 - 14 V



< 1 V

Wiring,
S9/1.
11.0   Parking brake switch (S12)

 

47 (2.40)
N30/1


 

68
(1.6)

 Ignition: ON

Apply parking brake.


Engine: at Idle
Parking brake not applied.
A1e7: ON
< 1 V





A1e7: OFF
11 - 14 V		 Wiring,
Parking brake indicator lamp (A1e7).
12.0   ASR snow chain switch (S76)

 

40 (2.40)
N30/1


 

55 (1.14)

 Engine: at Idle

Press and hold switch S76 in ON position.

Press and hold switch S76 in OFF position.



< 1 V
S76 indicator: ON


11 - 14 V
S76 indicator: OFF
Wiring,
S76,
N30/1.
13.0

Model 124.036 (02/92 ), 129.076, 140.04/05/07 		ABS lateral acceleration sensor (B24/2)
Voltage supply




Sensor signal at rest




Sensor signal dynamic

 

75 (1.34)

 


75 (1.34)

 


75 (1.34)

N30/1




N30/1




N30/1



 

64 (1.23)

 


42 1.1)

 


42
(1.1)

 Ignition: ON











Strongly shake vehicle in lateral direction.

4.75 - 5.25 V




2.35 - 2.65 V




> 0.01 V ~
Value changes with movement
Wiring,
B24/2,
13.1.
13.1   Voltage supply at sensor input

 

75 (1.34)

N30/1


 

64 (1.23)

 Ignition: ON
Remove connector from B24/2.

4.75 - 5.25 V		 Wiring,
N30/1.
14.0

Left front axle VSS
sensor (L6/1)

 

10 (2.10)

N30/1



 

30 (2.30)

 Raise front of vehicle
Ignition: ON
Rotate left front wheel.

> 0.1 V ~		 14.1,
14.2.
14.1   Insulation resistance

 

40 (2.40)
N30/1



 

30 (2.30)

Ignition: OFF

Disconnect N30/1 from contact box.


> 20 k		 Wiring
14.2   Internal resistance

 

10 (2.10)

N30/1



 

30 (2.30)

Ignition: OFF

Disconnect N30/1 from contact box.


0.8 - 3.7 k		 Wiring,
L6/1.
15.0   Left front axle VSS
sensor (L6/1) output

 

40 (2.40)

N30/1



 

77
(1.36)

Raise front of vehicle.
Ignition: ON
Rotate left front wheel.

> 3 V ~		 Wiring,
14.0,
15.1,
N30/1.
15.1   Load with control modules connected

 

40 (2.40)

N30/1



 

77 (1.36)

Ignition: OFF
Disconnect N30/1 from contact box.

> 5 k		 Wiring,
Control modules (N4/1, N4/3, N10/2, N22 or A2, A2/3y) connected.
16.0

Right front axle VSS
sensor (L6/2)

 

13 (2.13)

N30/1



 

34 (2.34)

Raise front of vehicle
Ignition: ON
Rotate left front wheel.

> 0.1 V ~		 16.1,
16.2.
16.1   Insulation resistance

 

40 (2.40)
N30/1



 

34
(2.34)

Ignition: OFF

Disconnect N30/1 from contact box.


> 20 k		 Wiring
16.2   Internal resistance

 

13 (2.13)

N30/1


 

34 (2.34)

 Ignition: OFF

Disconnect N30/1 from contact box.



0.8 - 3.7 k		 Wiring,
L6/2.
17.0   Right front axle VSS
sensor (L6/2) output

 

40 (2.40)

N30/1


 

79 (1.38)

 Raise front of vehicle.
Ignition: ON
Rotate right front wheel.

> 3 V ~		 Wiring,
16.0,
17.1,
N30/1.
17.1   Load with control modules connected

 

40 (2.40)
N30/1



 

79 (1.38)

Ignition: OFF
Disconnect N30/1 from contact box.

> 5 k		 Wiring,
Control modules (N16/1, N51) connected.
18.0

Left rear axle VSS
sensor (L6/3)

 

73 (1.32)

N30/1



 

74 (1.33)

Raise rear of vehicle.
Ignition: ON
Rotate left rear wheel.

> 0.1 V ~		 18.1,
18.2.
18.1   Insulation resistance

 

40 (2.40)

N30/1



 

74 (1.33)

Ignition: OFF

Disconnect N30/1 from contact box.


> 20 k		 Wiring.
18.2   Internal resistance

 

73 (1.32)
N30/1



 

74 (1.33)

Ignition: OFF
Disconnect N30/1 from contact box.

0.6 - 3.2 k		 Wiring,
L6/3.
19.0   Left rear axle VSS
sensor (L6/3) output

 

40 (2.40)

N30/1



 

69 (1.28)

Raise rear of vehicle.
Ignition: ON
Rotate left rear wheel.

> 3 V ~		 Wiring,
18.0,
19.1,
N30/1.
19.1   Load with control modules connected

 

40 (2.40)
N30/1



 

69
(1.28)

Ignition: OFF
Disconnect N30/1 from contact box.

> 5 k		 Wiring,
Control modules (N4/3, N49/1) connected.
20.0

Rear axle VSS sensor (L6/4)

 

71 (1.30)

N30/1



 

72 (1.31)

Raise rear of vehicle.
Ignition: ON
Rotate right rear wheel.

> 0.1 V ~		 20.1,
20.2.
20.1   Insulation resistance

 

40 (2.40)

N30/1



 

72 (1.31)

Ignition: OFF

Disconnect N30/1 from contact box.


> 20 k		 Wiring.
20.2   Internal resistance

 

71 (1.30)

N30/1



 

72 (1.31)

Ignition: OFF
Disconnect N30/1 from contact box.

0.6 - 3.2 k		 Wiring,
L6/4.
21.0   Rear axle VSS sensor (L6/4) output

 

40 (2.40)

N30/1



 

67 (1.26)

 Raise rear of vehicle.
Ignition: ON
Rotate right rear wheel.

> 3 V ~		 Wiring,
20.0,
21.1,
N30/1.
21.1   Load with control modules connected

 

40 (2.40)

N30/1



 

67 (1.26)

Ignition: OFF
Disconnect N30/1 from contact box.

> 5 k		 Wiring,
Control modules (N4/3, N49/1) connected.
22.0



ABS/ASR hydraulic unit, pressure switch (A7/3s1)

 

37 (2.37)

N30/1



 

68 (1.27)

Engine: at Idle

Pressure reservoir full

Vent reservoir at connection "SP" for a maximum of two seconds.
9 - 14 V



< 3 V

22.1,
33 1.0, 2.0,
Pressure reservoir is empty.

Wiring,
A7/3.
22.1   Pressure switch


W14




N30/1

37 (2.37)
Ignition: ON
Disconnect relay (A7/3k1) from hydraulic unit.
Disconnect N30/1 from contact box.

Pressure reservoir: Full

Pressure reservoir: Empty







 






< 1.8 k

> 20 k

 Wiring,
A7/3.
23.0 ABS/ASR hydraulic unit, left front axle solenoid
valve (A7/3y1)
Internal resistance

 

20 (2.20)

N30/1


 

21 (1.21)

 Ignition: OFF
Disconnect N30/1 from contact box.

0.7 - 2.2 		Wiring,
A7/3.
24.0 ABS/ASR hydraulic unit, right front axle solenoid
valve (A7/3y2)
Internal resistance

 

39 (2.39)
N30/1


 

21 (1.21)

 Ignition: OFF
Disconnect N30/1 from contact box.

0.7 - 2.2 		Wiring,
A7/3.
25.0   ABS/ASR hydraulic unit, left rear axle solenoid
valve (A7/3y3)
Internal resistance

 

2 (2.2)

N30/1


 

21 (1.21)

 Ignition: OFF
Disconnect N30/1 from contact box.

0.7 - 2.2 		Wiring,
A7/3.
26.0 ABS/ASR hydraulic unit, right rear axle solenoid
valve (A7/3y4)
Internal resistance

 

24 (2.24)

N30/1


 

21
(1.21)

 Ignition: OFF
Disconnect N30/1 from contact box.

0.7 - 2.2 		Wiring,
A7/3.
27.0 ABS/ASR hydraulic unit, switchover/solenoid
valve (A7/3y5)
Internal resistance

 

5 (2.5)
N30/1


 

21 (1.21)

 Ignition: OFF
Disconnect N30/1 from contact box.

1.8 - 3.0 		Wiring,
A7/3.
28.0


CAN data bus

L
N30/1

H
 Ignition: OFF
Disconnect N30/1 or contact module 2.
Connect ohmmeter directly to both wide terminals on N30/1 connector.





55 - 65 		CAN data line,
28.1.
28.1   CAN element in LH-SFI or engine control module (N3/1, N3/4 respectively)
Resistance

 


L

Engine 104, 119
N3/1

 


H

 Disconnect N3/1 or N3/4.
Test directly on control module.

115 - 125 		N3/1 or N3/4,
28.2.
28.2   CAN element in DI control module (N1/3, N1/4, N1/5)
Resistance

 

 



3

 

 

3

Engine 104 LH-SFI, Engine 119 LH-SFI
N1/3


Engine 120
N1/4
N1/4








4





4

Disconnect connector "B" from N1/3.
Test directly on control module.


Disconnect connector "B" from control modules N1/4 and N1/5.
Test directly on control modules.
115 - 125


N1/3






N1/4, N1/5
29.0

Model 140.032 (06/93 ) VSS sensor output status
Signal: Vehicle stationary


40 (2.40)
N30/1




44 (1.3)

Ignition: ON

> 3 V ~		 29.1
29.1   Signal: Fault

 

40 (2.40)
N30/1



 

44 (1.3)



Ignition: ON

< 10 V		 14.0,
N30/1.



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