Chapter 3 HVAC Tools, Equipment, and Service Information 61
❑
Follow the on-screen directions to begin repro-
gramming. Reprogramming times vary, from 2-3 min-
utes to over an hour. If using the manufacturer’s service
information Web site, high-speed Internet access is
recommended to reduce download times.
❑
After the vehicle has been reprogrammed, attach a
scan tool to the vehicle DLC and follow the on-screen
directions to allow the ECM to relearn the vehicle
operating characteristics.
The Environmental Protection Agency requires
vehicle manufacturers to make reprogramming information
available to non-dealer shops through the manufacturer’s
service information websites and requires manufacturers to
use SAE interface standard J2534. However, this regulation
applies only to vehicle ECMs that affect emissions—usually
the engine and transmission/power train ECMs. Emissions-
related reprogramming information is given the designation
J2534-1. Non-emissions related reprogramming informa-
tion is designated with J2534-2.
Manuals on CD-ROM
Service literature, including service, parts, and
labor time manuals are available in compact disc format.
CD-ROM stands for compact disc-read only memory.
A CD-ROM is a compact disc identical in appearance
to music CDs. However, this type of CD contains ser-
vice information. One CD-ROM can provide the same
amount of information found in a complete series of
printed manuals. Many CD-ROM manuals cover sev-
eral model years of a particular manufacturer’s line of
vehicles. Some of the newest CD-ROM manuals show
actual, step-by-step footage of certain repair operations.
The CD-ROM disc can be inserted in a computer with a
CD drive. The information is then accessed and read on
the computer monitor, Figure 3-46. The one drawback to
CD-ROM manuals is they are much more expensive than
a printed manual.
Internet Resources
By using a computer on-line service, small shops can
access any one of several automotive central information banks
over the information superhighway. These banks can offer
diagnostic tips, technical service bulletins, and other service
information similar to the telephone hotlines described earlier.
Many of these services have interfaces that make them easy
for anyone to use. Most of these on-line assistance centers are
operated by aftermarket companies, private organizations, and
individuals. These organizations provide a way for technicians
from around the world to help each other by way of e-mail.
Summary
There are two kinds of HVAC equipment; test equip-
ment and service equipment. Some test equipment, such as
gauge manifolds, are both diagnosis and service tools. Most
test equipment is dedicated, that is, it can only be used for
one purpose. In addition, many refrigeration system test and
service tools can be used with only one type of refrigerant.
HVAC test and service equipment can be simple (such
as gauge manifolds or test lights) or extremely complex (such
as charging stations and scan tools). When using any type
of HVAC tools, always be careful not to damage the HVAC
system or cause a release of refrigerant into the atmosphere.
Cooling system test and service equipment is used to
check for leaks and pressure problems. Always allow the
cooling system to cool off and remove all pressure before
performing any test or service operations.
Many times the most important tools are the proper
service literature or other sources of service information.
Never guess at specifi cations or service procedures.
Review Questions—Chapter 3
Please do not write in this text. Write your answers on
a separate sheet of paper.
1. A refrigeration gauge manifold body is made of _____
or _____.
2. The blue handwheel on a gauge manifold indicates
the _____ side valve.
3. Some R-12 refrigeration systems may have special
service fi ttings. These fi ttings keep the technician
from doing what?
4. Defi ne refrigeration system static pressure.
5. Mechanical temperature gauges make use of a _____
spring to register temperature changes.
6. The most accurate way to check for leaks is to use
a(n) _____ leak detector.
7. Older refrigerant dyes were _____ in color.
8. What color are contaminated refrigerant containers?
Figure 3-46. Modern service literature is often provided in the
form of CD-ROMs. These discs can hold the equivalent of
thousands of pages of service documents.