Porsche 928 Workshop Manual page 590

928 s4
928 GT Electronic Fuel Injection
24
Fault, Fault Code
Test point 3
Full load contact R
Fault code l-13
Possible Causes, Elimination, Remarks
Check by means of circuit input test with a 9288 system tester or
9268 tester
Select test step and operate the accelerator pedal,
9268 display: Full load contact open
Full load contact closed.
9268 display: 1333 (full load contact open)
0000 (full load contact closed).
No display:
After disconnecting the EZK and LH control unit plugs, connect the
ohmmeter to terminals 3 and 5 by means of the test leads.
35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 2Q 19
w
16 17 16 15 14 13 12 11 10 9 6 7
6 5
4 3 2 1 j
4 4
Display:
Throttle valve closed mS1
Throttle valve after opening by
approx. two-thirds of its travel < 10R
If the full load contact values are not reached in this test, it should be
repeated directly at the throttle valve switch:
Disconnect plug at throttle valve switch. Connect ohmmeter between
terminals 3 and 2 of the throttle valve switch by means of the test
leads.
Display:
throttle valve closed
Throttle valve open
Note:
If the full load contact failsm the control unit generates a load thre-
shold by way of the air mass sensor. Values below thisload are the
same as if the switch were open, values above it the same as if the
switch were closed.
l
LH-Diagnosis/Troubleshooting
Printed in Germany - XXV, 1990
D24-13