Snap-On Diagnostics DGA 1000, Manual, Page: 39 / 116

Analyzer Screen Display Features
2-7
Leak check (vacuum)
This test determines if there is an air leak in the gas sample
handling system of the analyzer. Follow the instructions on the
screen. Press Enter or the right arrow (
) to begin the test.
✓
The exhaust sample probe must be blocked for this test.
The pump draws a vacuum and the analyzer checks for
any leaks in the system. It is advised to perform a Leak
check often. Refer to
Chapter 4–Maintenance .
Leak check (gas)
This test checks if there is an air leak in the gas handling sample
system of the analyzer using vehicle exhaust. Follow the
instructions on the screen. Press Enter or the right arrow (
) to
begin the test.
✓
The exhaust sample probe must be inserted in the exhaust
of the vehicle. The pump draws exhaust gases into the
system, the exhaust sample probe must be blocked and
then system checks if the
CO
2
value changes. When the
CO
2
change exceeds a certain value, a leak is present in
the sample system. Refer to
Chapter 4–Maintenance
for
additional details.
Gas calibration check
This test checks the gas measurement system with use of a
calibration gas which has a known concentration of various gases.
This mixture is determined by local authorities and is used to
calibrate emission analyzers. Refer to
Chapter 4–Maintenance for
additional details.
O
2
cell check/install
This test checks the O
2
cell in the analyzer. Follow the instructions
on the screen. Press Enter or the right arrow ( ) and ENTER as
prompted.
✓
The analyzer indicates when to replace the O
2
cell. Refer
to
Chapter 4–Maintenance
.
Figure 2-6 : Maintenance Screen