|
Test
Step No.
|
Test
Equipment Multimeter MKM - 587 - A
|
Test
of
|
Terminal
|
Notes
|
Nominal
Values
|
Possible
Cause of Fault, Trouble - shooting
|
|
|
1
|
Ohmmeter
|
Diagnostic plug (ALDL): ground
|
4 / ground
or
5 / ground
|
Ignition OFF
|
approx. 0
|
· Transfer resistance at grounding point
too high
|
|
|
2.1
|
Ohmmeter
|
Diagnostic plug (ALDL):
excitation lead
|
X D / Ter. 6 and K 61 / Ter. 13
|
Ignition OFF
|
approx. 0
|
· Lead interruption between X D / Ter. 6
and K 61 / Ter. 13
|
|
|
2.2
|
Ohmmeter
|
Diagnostic plug (ALDL):
excitation lead
|
X D / Ter. 6 and ground
|
Ignition OFF
|
infinite
|
· Short circuit to ground
· Control unit K 61 defective
|
|
|
3
|
Voltmeter range: 20 V DC
|
Diagnostic plug (ALDL): voltage
supply
|
16 / ground
|
Ignition OFF
|
greater than 11.5 V
|
· Battery voltage too low
· Lead interruption between X D / Ter. 16
and voltage supply
· Fuse F 12 defective
|
|
|
4.1
|
Ohmmeter
|
Diagnostic plug (ALDL): data
lead
|
X D / Ter. 7 to K 61 / Ter. 55
|
Ignition OFF
|
approx. 0
|
· Lead interruption between X D / Ter. 7
and K 61 / Ter. 55
|
|
|
4.2
|
Ohmmeter
|
Diagnostic plug (ALDL): data
lead
|
X D / Ter. 7 and ground
|
Ignition OFF
|
infinite
|
· Short circuit to ground
· Control unit K 61 defective
|
|
|
5.1
|
|
Telltale H 30
|
-
|
Ignition ON
|
Telltale ON
|
· Telltale H 30 defective
· Fuse F 15 defective
· Lead interruption between H 30 and K 61
/ Ter. 22
|
|
|
5.2
|
|
Telltale H 30
|
-
|
Engine running Ensure that no
trouble codes are stored
|
Telltale OFF
|
· Control unit K 61 defective
|
|
|
5.3
|
|
Telltale H 30
|
-
|
Ignition OFF Disconnect control
unit Ignition ON
|
Telltale OFF
|
· Short circuit
between H 30 and ground
|
|
|
6
|
|
TECH 1 self - test DCL adapter
|
-
|
See TECH 1 Operating
Instructions
|
-
|
-
|
|
|
|
Note: After test steps 7 and 8, any stored
trouble codes are deleted.
|
|
7
|
Ohmmeter
|
Control unit plug K 61: ground
|
Ter. 141 ground Ter. 191 ground
Ter. 241 ground
|
Ignition OFF Disconnect plug
from control unit K 61
|
approx. 0
|
· Transfer resistance at grounding point
too high
· Lead interruption between K 61 and
grounding point
· Control unit K 61 defective
|
|
|
8
|
Voltmeter range: 20 V DC
|
Control unit plug K 61: voltage
supply Ter. 30 and Ter. 15
|
Ter. 181 ground Ter. 27 / ground
|
Ignition OFF Disconnnect plug K
61 Ignition ON
|
greater than
11.5 V
|
· Battery voltage too low
· Lead interruption between Ter. 30 or
Ter. 15 and control unit K 61
· Vehicles with ATWS and / or
immobilizer: ATWS and / or immobilizer in operation or defective
· Fuel pump relay K 44 defective
· Control unit K 61 defective
|
|
|
9
|
Voltmeter range: 20 V DC
|
Injectors relay K 43 Voltage
supply, control unit Ter. 37
|
Ter. 37 / ground
|
Ignition ON
|
greater than
11.5 V
|
· Battery voltage too low
· Lead interruption between injectors
relay K 43 and control unit K 61
· Lead interruption between Ter. 30 and
injectors relay K 43
· injectors relay K 43 defective
· Control unit K 61 defective
|
|
|
10
|
-
|
Auxiliary fan, electronics box M
28
|
-
|
Ignition ON
|
Auxiliary fan in electronics box
running
|
· Fuse F 50, F 15 defective
· Auxiliary fan M 28 defective
· Fan relay K 26 defective
· Coolant temperature switch
|
|
