MACS Monthly Newsletter - 2017 - FEB5

along with an A/C power supply. The identifier meets
SAE J1771. If you're still holding off on R-1234yf, this
identifier still has been filling your needs.
J1771 is an older standard, but it is still in effect, even
though the newest identifier standard, J2912, was adopted to update the industry to R-1234yf.
The first hand-held identifier to meet J2912 is Neutronics RI-2012yfp, the second in the Ultima series. It's been
supplied with a built-in printer, built-in rechargeable battery, sampling hoses for both R-134a and R-1234yf vehicle systems and tank adapters for both refrigerants and
of course a USB cable. In addition to the two refrigerants,
it detects R-22, hydrocarbons, air and unknown refrigerants, the latter a tipoff to such problematic refrigerants
as R-40 (methyl chloroform), which can pose dangers in
certain conditions.
The newest choice is Neutronics Legend series (FIG. 6),
first model since the two "Ultima" editions, and just coming on the market. You can still buy the RI-2012, but the
Legend has more features and will likely cost the same.
The big new feature is that it includes high-accuracy detection of R-12, along with (of course) R-134a, R-1234yf,
R-22, hydrocarbons, air and unknown refrigerant (including the already-noted R-40). At this point, why would
you care about R-12? The answer is that there are many
older cars on the road (pre-1996) that were equipped
with R-12 and their owners see no reason to change over
what continues to be a reliable system. In addition, some
shops (maybe yours) maintain a supply of R-12 on the
storeroom shelf and have a few customers that fit this

category. Additionally, if your shop becomes known as a
source of R-12 system service, it might bring in some new
customers. At the same price as the RI-2012yfp, what's
the downside if you need an identifier for R-1234yf? You
might wonder why the Legend does not also meet SAE
J1771, but the simple reason is that the test procedure for
that standard includes procedures with other refrigerants not commonly available today and which would require a new, very expensive laboratory test procedure.
There are some other advantages to the Legend, depending on your business location. The Legend handles
multiple languages, including Spanish (many states have
large Hispanic populations and you may be employing
a technician who is more comfortable in that language.
Ditto for Russian in some parts of the U.S., including
Brooklyn, NY. And of course, Canadian shops may find
the French language selection important. The Legend is
Neutronics' first unit with Bluetooth optional, instead of
a conventional USB terminal, which provides a wireless
connection to recovery/recycle/recharge machines that
cover R-1234yf.
Although the Legend identifier comes with hoses and
tank adapters for R-134a and R-1234yf, a built-in printer
that uses paper available in office supply stores, and an
internal rechargeable battery, the R-12 quarter-flare fitting is an option (surely any shop still stocking R-12 has
the needed hose, etc.).
The Legend comes with a 5-inch color screen, not exactly on our list of essential features, but you'll probably
like it. ■

WHEN THERE'S MORE THAN ONE
One of the easiest ways to misdiagnose a problem is
when you're looking at (and/or) replacing the wrong
part. The way that occurs most often is when you're testing relays, because so many are standard "Bosch"-type
relays and you pick the wrong one, because the one you're
looking for is in the "wrong place." Wiring harnesses get
changed so often during the production period, even including a single model year, it's easy for that to happen.
Hopefully your on-line information system has the latest
information, but often your only confirmation may be the
color coding of the wiring at a relay, solenoid, etc.

send the one signal across the busses and the ones that can
use the information will pick it up. The simple answer is
that taking coolant temperature at one point in today's complex cooling systems may not provide enough information,

COOLANT TEMPERATURE SENSORS

February 2017

techauthority.com

But just as difficult is when you don't realize that the part
you see (and replace) is not the one that applies to the system you're testing. One of the most common areas in recent
years was the coolant temperature sensor, as many cars had
two or three, even four, and only one applied to the primary
HVAC control circuit, another to the engine control system,
and still another to one of those, but with a special purpose.
It would seem that with the multiple data busses and the
gateways that let them communicate with each other, that
a single coolant temperature sensor would be enough-just

Figure 7: Primary thermostat on Fiat Chrysler 2.4-liter four-cylinder
in Jeep Patriot/Compass.

MACS Service Reports

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Table of Contents for the Digital Edition of MACS Monthly Newsletter - 2017