◆
Current flow diagram
Test prerequisites
● Fuses must be OK.
● The battery voltage must be at least 11.5 V.
● All electrical consumers must be switched off.
● Earth connections OK
● Exhaust system must be free of leaks.
● Check whether lambda probe heater -Z19- is OK
.
Test procedure
Note
◆
The lambda probe -G39- and lambda probe heater -Z19- are
installed in one common housing.
◆
Only gold-plated contacts may be used when repairing con-
tacts in connector of lambda probe and lambda probe heat-
er.
– Disconnect 6-pin connector from lambda probe -G39-
.
Checking basic voltage
– Connect multimeter to contacts 2 + 6 of connector using test
leads from -V.A.G 1594- to measure voltage.
– Switch on ignition. Check basic voltage after approx. 8 sec-
onds. Specification: 0.4...0.5 V
– Switch off ignition.
If the specification is not attained:
– Check wiring of lambda probe as follows:
– Using adapter cable -V.A.G 1598/39-2-, connect test box
-V.A.G 1598/42- to wiring harness of control unit
The engine control unit is not connected by this action.
– Check wiring between test box and connector for open cir-
cuit referring to current flow diagram.
◆
Contact 1 + socket 77
◆
Contact 2 + socket 56
◆
Contact 5 + socket 55
◆
Contact 6 + socket 78
● Cable resistance: max. 2.0 Ω.
– Additionally check wires for short to one another. Specifica-
tion: ∞ Ω
If no wiring fault is detected and voltage was present between
contacts 2 + 6:
– Renew lambda probe -G39-
, Assembly over-
view - diesel particulate filter.
3
Industriemotoren - Industrial Engines 2009
▶
Workshop Manual for Diesel Engine (2.0 l/36-75 kW_EA 189) 05.2015
440
Repair Group 26 - Exhaust system