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Diagnostic Manual, Engines, Volume 2

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 5.2 Electronic Ignition System with Anti-Knock Control (EZL/AKR)   >   24 Electrical Test Program - Test (Engine Runs)


Electrical Test Program - Test (Engine Runs)

Test scope  
Test condition Nominal value Possible cause/Remedy
1.0 6 CMP sensor (L5/1)

13
(B.5)




13
(B.5)
N1/3 1)





N1/3 2)



9
(B.1)




9
(B.1)
Connect to N1/3

Engine: at Idle





Engine: at Idle

Signal, see
25 , figure 3.




> 0.3 V~ 3) 		Open circuit,
1.1 ,
1.2 ,
Engine 119: Check distance between CMP sensor (L5/1) and contact sensor (see SMS, Repair Instructions, Group 15,
Job No. 2143).
1.1 6 Resistance of L5/1

13
(B.5)
N1/3



9
(B.1)
Unplug test cable at connector (B) on DI control module (N1/3) ( 25 , Figure 5).
900 - 1600 L5/1.
1.2 6 Insulation of L5/1

2
(A.2)
N1/3



9
(B.1)
Unplug test cable at connector (B) on DI control module (N1/3) ( 25 , Figure 5).
> 200 k L5/1.
2.0 1 7 CKP sensor (L5)

18




18
N1/3 1)




N1/3 2)



17




1 7


Engine: at Idle




Engine: at Idle
Signal, see
25 , figure 1 and 2.




> 1 V~ 3) 		Open circuit,
1.1 ,
1.2 ,
Starter ring gear segments.
2.1 1 7 Resistance of L5

18
N1/3



17
Ignition: OFF
Unplug connector (2) for L5 at DI control module (N1/3) ( 25 , Figure 5).
680 - 1200 L5.
2.2 1 7 Insulation of L5

2
(A.2)
N1/3



17
Ignition: OFF
Unplug connector (2) for L5 at DI control module (N1/3) ( 25 , Figure 5). 		> 200 k L5.
3.0 1 8 Magnets for CKP sensor

Engine 119 only

18
N1/3



17
Engine: at Idle Signal see
25 , Figure 2. 		Segments on starter ring gear.
4.0 1 1 Reference resistor (R16/2)
R16/2

Ignition: OFF
Unplug R16/2 at DI control module (N1/3) ( 25 , Figures 4 and 5).
2.4 k R16/2.
5.0 4) 8 Transmission overload protection switch (S65)
Does not close

2
(A.2)
N1/3



10
(B.2)
Depress parking brake.
Engine: at Idle
Selector lever in "D". 		< 1 V Open circuit,
S65.
6.0 4) 9 Transmission overload protection switch (S65)
Does not open

2
(A.2)
N1/3



10
(B.2)
Engine: at Idle
Selector lever in "P" or "N". 		> 4 V Short circuit,
S65.
7.0 1 2 TN-signal (engine rpm output)
Outside of tolerance range

2
(A.2)
N1/3



4
(A.4)
Engine: at Idle 5 - 7 V 7.1 ,
DI control module (N1/3),
LH-SFI control module (N3/1).
7.1 1 2 TN wire to LH-SFI control module (N3/1)

2
(A.2)
N1/3



4
(A.4)
Unplug N3/1.
Unplug test cable at connector (B) on DI control module (N1/3) ( 25 , Figure 5).
> 200 k Short circuit.
8.0 2 6
2 7
2 8 		CAN databus

3
N1/3
(B)


4
Ignition: OFF
Unplug connector (B) without test cable at DI control module (N1/3) and test directly at connector (B) ( 25 , Figure 7).
115 - 125 8.1 ,
Databus.
8.1 2 7 CAN element in LH-SFI control module
Resistance
N3/1

Unplug LH-SFI control module (N3/1) and test directly at N3/1 ( 25 , Figure 8). 115 - 125 N3/1.
9.0 2 6 CAN element in DI control module
Resistance
3
N1/3

4
Ignition: OFF
Unplug connector (B) without test cable at DI control module (N1/3) and test directly at N1/3 ( 25 , Figure 9).
115 - 125 N1/3
1) Test with oscilloscope.
2) Test with multimeter only if oscilloscope is not available.
3) Voltage increases with increasing rpm.
4) Test steps 5.0 and 6.0 cannot be performed on model 124.034 (400 E). If DTC's 8 or 9 are displayed, proceed as follows:
Replace transmission overload protection switch (S65),
Clear DTC memory,
With transmission in driving range "2", drive vehicle for at least 2 seconds at an engine speed greater than 3000 rpm and subsequently shut engine OFF,
Repeat DTC readout. If fault still exists, check wiring.


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