Volkswagen CJDA Workshop Manual page 72

3
Industriemotoren - Industrial Engines 2009 ▶
Workshop Manual for Diesel Engine (2.0 l/36-75 kW_EA 189) 05.2015
Indicated on display
Short to positive
01588/P0634
Control unit, temperature
shut-off
01601/P0641
Sender reference voltage
"A"
56 Repair Group 01 - Vehicle self-diagnosis
Possible cause of fault Possible effects
◆ Wiring open circuit or
wiring short to posi-
tive
◆ Fuel pump relay -J49-
defective
◆ Engine control unit
-J623- defective
◆ Overload on output
stage(s) in -J623-
◆ Glow plug control
module is switched
off
◆ Very high ambient
temperature
◆ Engine control unit
not installed correctly
◆ Internal defect in en-
gine control unit
-J623-
◆ Engine failure
◆ Possible smoke when
starting engine
◆ Entire glow plug sys-
tem does not work
◆ Possible bad cold
start behaviour of en-
gine
Fault remedy
– Pull off relay, and read
event memory again
– If in addition PSPOL--
> renew relay
– Otherwise, check wir-
ing between relay and
ECU
– Check wires between
-J49- and -J623-,
⇒ P age
486, current
flow diagrams
– If OK, renew control
unit.
– -J623- Allow to cool
off, and clear event
⇒ P age 27
memory
– If necessary, renew
ECU -J623-
⇒ P age 418