Tests - Porsche 928 Workshop Manual

928
Differential. transaxle svstem
39
a
- Bleed pressure gauge (No. 1). To
do this,
connect a collection bottle to the pressure
gauge bleeder valve (No. la) and open the
valve.
Turn ignition key to position 2 (necessary
for pump operation).
Plug the electrical plug onto the pump.
Di-
sconnect the electrical plug and close
the bleeder valve
as soon as no air bub-
bles are visible anymore in the transparent
bleeder line of the collection bottle.
Make sure that the brake fluid reservoir is
not sucked empty. Fill in brake fluid from
time to time if necessary.
3. Tests
Note
Operation of the pump is regulated by means
of the ignition key for testing purposes.
Position 0 = Pump
off
Position 2 = Pump on until switched off by
the pressure warning switch.
Depressurize the lock hydraulics before re-
moving the pressure gauge after the test.
. .
1
- In ignition key position 0, plug the electrical
plug onto the pump. Locate the pressure
gauge in a position where it can be seen.
For the tests, it is expedient to observe the fol-
lowing sequence:
a. Pressure reservoir - gas filling pressure
b. Switching points for the warning display
"PSD off"
c. Cut-in and cut-out points of the pump
d. Leak test
- Turn the ignition key to position 2 (pump
starts up).
a
PSD diagnosisfkoubleshooting
Printed In Germany - XXXV, 1995
D39 - 253