Volkswagen CJDA, Руководство по ремонту

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– To do this, connect an oscilloscope, and check engine speed
sender -G28- with a signal voltage of 0 - 5 V. The sender
must provide an approximate square wave signal.
– In addition, measure resistance of sender.
◆
Between contacts 2 + 3 of connector, specification 480 ...
1000 Ω
◆
Check sender for short-circuit to shielding.
◆
Between contacts 1+2 as well as 1+3 specification ∞ Ω
If the specifications are not obtained
– Renew engine speed sender -G28-
⇒
Page 178 .
– Then, read event memory of engine control unit, and clear
event memory if necessary
⇒
Page 26 , read event memory.
If the specifications are attained:
Checking voltage supply
– Connect multimeter to contacts 1 + 3 of connector using test
leads from -V.A.G 1594- to measure voltage.
– Switch on ignition. Specification: at least 4.8... 5.2 V
– Switch off ignition.
If the specification is not attained:
– Check wiring of engine speed sender as follows:
– Using adapter cable -V.A.G 1598/39-1-, connect test box
-V.A.G 1598/42- to wiring harness of control unit
⇒
Page 24 .
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 25
◆
Contact 2 + socket 52
◆
Contact 3 + socket 53
● Cable resistance: max. 2.0 Ω.
– Also check wiring for short to one another, short to battery
earth/engine earth and short to battery positive. Specifica-
tion: ∞ Ω
If no fault in lines is detected:
– Remove engine speed sender -G28-
⇒
Page 178 .
– Check sender wheel for:
◆
firm seating,
◆
damage,
◆
run-out,
◆
metal shavings on sender wheel or sender.
If no fault is detected on the sender wheel or in the wiring, and
voltage was present between contacts 1 + 3:
3
Industriemotoren - Industrial Engines 2009
▶
Workshop Manual for Diesel Engine (2.0 l/36-75 kW_EA 189) 05.2015
402 Repair Group 23 - Mixture preparation - injection