ACtion Magazine - June 2017 - 20

Today's technicians need to be total climate control management forensic scientists

Be organized.

Always check your electrical system baselines.
Shown here we have both the Key on Engine Off and Key on
Engine running voltages. If you're performing electrical system
tests, it probably wouldn't hurt to make sure you have the correct size battery in the vehicle while you're at it. Obviously, that
wouldn't have to be done if we were the only one performing the
maintenance on the vehicle. However, if this is a first-time customer with no previous work history, you may want to check it.

When working on a complaint for inadequate heat or coolness,
technicians need to focus on TOTAL CLIMATE CONTROL Management ... NOT Just A/C! Don't just look. Inspect everything,
understand the system, check and validate system performance per
OEM specs... not your specs!
Example Case Study: The complaint is the A/C clutch is not
engaging. Is it electrical malfunction or a TRUE A/C performance
problem? No or low refrigerant can cause the PCM to turn off the
A/C compressor, or you may have a genuine power supply or ground
problem to the clutch or an open A/C clutch. MAKE SENSE?
Let's examine one:
Vehicle is a 2003 Ford Windstar 3.8L with, if you can believe this,
456,000 miles on it. Plus, it runs great!
Customer complaint: A/C blowing warm air
Conditions and Findings:
* Ambient temperature is 94 degrees
* Customer complaint verified: system blowing warm air
with A/C requested on
* Static A/C pressures for the day are satisfactory
* Customer is upset ... wouldn't you be?

We'll perform some basic operational tests and move on to
more OE specific or component level tests when we have authorization to do so. Here we have the car running at idle and the A/C
requested to turn on. Remember, we are collecting information
here and should NOT be trying to fix the car during this process.
We are ANALYZING!
Peter Orlando - Automotive
Training Technologies

Analyzing scan tool data if you can capture it with your scan
tool isn't a bad idea. This information is showing us NO Faults in
the low or high fan control circuits.
Peter Orlando - Automotive
Training Technologies

Peter Orlando - Automotive Training Technologies

Peter Orlando - Automotive Training
Technologies

I've said many times that auto mechanics should be organized. If you look and analyze any field, you'll notice that successful individuals are organized. Your tools and test equipment
need to be neat and in order. If you must look for it or you can't
find it, you will NOT test it or do it! Try and stay focused and
avoid service interruptions. (I'll admit, not an easy task in an automotive repair establishment.)
If you're checking any electrical measurements, write down
the answers to the test measurement you're making. Do not attempt to memorize results; this will come back to bite you later
in the diagnostic process. Besides, all the tests that were done
and the results of those tests are all going to make up the basis for
the invoice. Everything will be transferred over to the work order and become the customer's bill in the end. If you must walk
away from the job temporarily to work on another vehicle, you
won't have to remember where you left off if you keep accurate
diagnostic notes. I see many technicians taking digital notes on
tablets and smart phones now, which can only augment the repair process and assist with accurate invoicing.

Below we see the electrical schematic for the A/C clutch circuit and need to determine where we would place our test equipment to make an accurate test. Common point diagnostics is a
very smart, effective way to determine where any deficiencies

ACTION * June 2017

Table of Contents for the Digital Edition of ACtion Magazine - June 2017