
RENR9348-01 95
Troubleshooting Section
Emergency Stop Sequence – The third condition
occurs when the
emergency stop switch is activated.
When the emergency stop switch is placed in the
STOP position, voltage is supplied to the relay control
for the ECM rel
ay. The ECM relay removes electrical
power from the ECM. Voltage is also supplied to the
air shutoff timer. The air shutoff timer supplies voltage
to the air shu
toff relay for 2.5 seconds. This latches
the air shutoff valves in the closed position. The timer
has been placed in the circuit in order to prevent the
shutoff sol
enoids from being powered for extended
periods.
After the ai
r shutoff mechanism has been tripped, a
manual reset of the mechanism is necessary.
g01209014
Illustration 1 3
Schematic for the air shutoff sy stem
Test Step 1. Inspect the Electrical
Connectors and the Wiring
A. Turn the battery disconnect switch to the OFF
position.
B. Verify that the air shutoff mechanisms are set to
the OPEN position.