Porsche 944 Automobile User Manual


 
944 S/944 S2 Fuel System - Electronic Control
24/28
Fault, Fault Code Possible Causes, Elimination, Remarks
Test
Point
1a
Power
supply for
DME
control unit
(V)
a) Perm. pos. (B + )
Fault memory is cancelled, if there is
no B +.
Testing:
Connect a voltmeter on terminal 24 (-) and terminal 18 ( +) of the control unit plug
with help of test leads.
Display: battery voltage
No display: check current flow and ground paths according to the wiring diagram.
Test Point
1b
Power
supply for
DME
control unit
(V)
too high /
too low
Fault Code
1_11
b) Power supply via DME relay
Connect a voltmeter on terminal 24 (-) and terminal 37 (+) of the control unit plug
with help of test leads. Turn on ignition.
Display: battery voltage
No display: check current flow path according to the wiring diagram.
Remarks:
Cars with burglar alarm: check power supply from ignition lock via burglar alarm
control unit to terminal 86 af the DME relay according to the wiring diagram.
Cars without burglar alarm: check pin bridges on plug (provided for installation
of a burglar alarm control unit).
DME - Diagnosing/Troubleshooting
Printed In Germany - XXI, 1989
D 24/28 - 9