MACS Monthly Newsletter - 2017 - JUN8
6. Don't forget other causes such as leaking
alternator diodes. Test for this by removing
the heavy gauge output cable at the alternator to see if the drain goes away.
7. Finally, hopefully you pulled DTCs from
every module on board before jumping very
deep into such a problem. Sometimes the
pattern of U-codes (communications) gives
you a clue when an electronic module is to
blame for the parasitic drain.
sory activations, opening and closing the
trunk, glove box and hood looking for sticky
switches that might cause a light to stay on
when it should be off, etc.) in order to try to
get an intermittent parasitic drain to occur.
3. If there is a larger than normal parasitic
drain, the ohmmeter will read a 'false positive'. A false positive would be a resistance
reading that is much higher than expected.
Several ohms up to 50 or more ohms (Fig. 14)
depending on which way you've connected
your leads, an ohm reading that is negative!
4. If the outcome to step 3 is positive (more
than the expected ohms of resistance in a
known good ground circuit) it's time to connect your ammeter / parasitic drain switch,
etc. to verify / quantify the drain.
5. Next follow up with narrowing down the
list of possible battery drain suspects by performing the fuse voltage drop test mentioned
earlier.
Finally, many techs are experimenting with infrared thermal imaging equipment to determine which
fuse (or electronic module) is the cause of a phantom battery drain. The temperature signature of
the culprit is slightly higher than its surroundings
thereby providing picture perfect evidence. The
same tool has many other uses ranging from HVAC
diagnostics to misfires. Not a bad idea. Since technology isn't standing still for us, we need to keep
our tools and techniques moving as well! ■
MACS Service Reports is published monthly by the Mobile Air Conditioning Society
Worldwide. It is distributed to members of MACS Worldwide and is intended for
the educational use of members of the automotive air conditioning service and
repair industry. Suggestions for articles will be considered for publication, however,
MACS Worldwide reserves the right to choose and edit all submissions.
Editors:
Elvis Hoffpauir, Steve Schaeber
Production Designer:
Laina Forcey
Manager of Service Training:
Steve Schaeber
Mobile Air Conditioning Society Worldwide
P.O. Box 88, Lansdale, PA 19446
Phone: (215) 631-7020 * Fax: (215) 631-7017
Email: membership@macsw.org * Website: www.macsw.org
Unless otherwise noted, all photos/art by author.
June 2017
8
MACS Service Reports
http://www.macsw.org
http://www.macsw.org
Table of Contents for the Digital Edition of MACS Monthly Newsletter - 2017
MACS Monthly Newsletter - 2017 - JAN1
MACS Monthly Newsletter - 2017 - JAN2
MACS Monthly Newsletter - 2017 - JAN3
MACS Monthly Newsletter - 2017 - JAN4
MACS Monthly Newsletter - 2017 - JAN5
MACS Monthly Newsletter - 2017 - JAN6
MACS Monthly Newsletter - 2017 - JAN7
MACS Monthly Newsletter - 2017 - JAN8
MACS Monthly Newsletter - 2017 - FEB1
MACS Monthly Newsletter - 2017 - FEB2
MACS Monthly Newsletter - 2017 - FEB3
MACS Monthly Newsletter - 2017 - FEB4
MACS Monthly Newsletter - 2017 - FEB5
MACS Monthly Newsletter - 2017 - FEB6
MACS Monthly Newsletter - 2017 - FEB7
MACS Monthly Newsletter - 2017 - FEB8
MACS Monthly Newsletter - 2017 - MAR1
MACS Monthly Newsletter - 2017 - MAR2
MACS Monthly Newsletter - 2017 - MAR3
MACS Monthly Newsletter - 2017 - MAR4
MACS Monthly Newsletter - 2017 - MAR5
MACS Monthly Newsletter - 2017 - MAR6
MACS Monthly Newsletter - 2017 - MAR7
MACS Monthly Newsletter - 2017 - MAR8
MACS Monthly Newsletter - 2017 - APR1
MACS Monthly Newsletter - 2017 - APR2
MACS Monthly Newsletter - 2017 - APR3
MACS Monthly Newsletter - 2017 - APR4
MACS Monthly Newsletter - 2017 - APR5
MACS Monthly Newsletter - 2017 - APR6
MACS Monthly Newsletter - 2017 - APR7
MACS Monthly Newsletter - 2017 - APR8
MACS Monthly Newsletter - 2017 - MAY1
MACS Monthly Newsletter - 2017 - MAY2
MACS Monthly Newsletter - 2017 - MAY3
MACS Monthly Newsletter - 2017 - MAY4
MACS Monthly Newsletter - 2017 - MAY5
MACS Monthly Newsletter - 2017 - MAY6
MACS Monthly Newsletter - 2017 - MAY7
MACS Monthly Newsletter - 2017 - MAY8
MACS Monthly Newsletter - 2017 - JUN1
MACS Monthly Newsletter - 2017 - JUN2
MACS Monthly Newsletter - 2017 - JUN3
MACS Monthly Newsletter - 2017 - JUN4
MACS Monthly Newsletter - 2017 - JUN5
MACS Monthly Newsletter - 2017 - JUN6
MACS Monthly Newsletter - 2017 - JUN7
MACS Monthly Newsletter - 2017 - JUN8
MACS Monthly Newsletter - 2017 - JUL1
MACS Monthly Newsletter - 2017 - JUL2
MACS Monthly Newsletter - 2017 - JUL3
MACS Monthly Newsletter - 2017 - JUL4
MACS Monthly Newsletter - 2017 - JUL5
MACS Monthly Newsletter - 2017 - JUL6
MACS Monthly Newsletter - 2017 - JUL7
MACS Monthly Newsletter - 2017 - JUL8
MACS Monthly Newsletter - 2017 - AUG1
MACS Monthly Newsletter - 2017 - AUG2
MACS Monthly Newsletter - 2017 - AUG3
MACS Monthly Newsletter - 2017 - AUG4
MACS Monthly Newsletter - 2017 - AUG5
MACS Monthly Newsletter - 2017 - AUG6
MACS Monthly Newsletter - 2017 - AUG7
MACS Monthly Newsletter - 2017 - AUG8
MACS Monthly Newsletter - 2017 - SEP1
MACS Monthly Newsletter - 2017 - SEP2
MACS Monthly Newsletter - 2017 - SEP3
MACS Monthly Newsletter - 2017 - SEP4
MACS Monthly Newsletter - 2017 - SEP5
MACS Monthly Newsletter - 2017 - SEP6
MACS Monthly Newsletter - 2017 - SEP7
MACS Monthly Newsletter - 2017 - SEP8
MACS Monthly Newsletter - 2017 - OCT1
MACS Monthly Newsletter - 2017 - OCT2
MACS Monthly Newsletter - 2017 - OCT3
MACS Monthly Newsletter - 2017 - OCT4
MACS Monthly Newsletter - 2017 - OCT5
MACS Monthly Newsletter - 2017 - OCT6
MACS Monthly Newsletter - 2017 - OCT7
MACS Monthly Newsletter - 2017 - OCT8
MACS Monthly Newsletter - 2017 - NOV1
MACS Monthly Newsletter - 2017 - NOV2
MACS Monthly Newsletter - 2017 - NOV3
MACS Monthly Newsletter - 2017 - NOV4
MACS Monthly Newsletter - 2017 - NOV5
MACS Monthly Newsletter - 2017 - NOV6
MACS Monthly Newsletter - 2017 - NOV7
MACS Monthly Newsletter - 2017 - NOV8
MACS Monthly Newsletter - 2017 - DEC1
MACS Monthly Newsletter - 2017 - DEC2
MACS Monthly Newsletter - 2017 - DEC3
MACS Monthly Newsletter - 2017 - DEC4
MACS Monthly Newsletter - 2017 - DEC5
MACS Monthly Newsletter - 2017 - DEC6
MACS Monthly Newsletter - 2017 - DEC7
MACS Monthly Newsletter - 2017 - DEC8
https://www.nxtbook.com/nxtbooks/macs/servicereports_2022
https://www.nxtbook.com/nxtbooks/macs/servicereports_2021
https://www.nxtbook.com/nxtbooks/macs/servicereports_2020
https://www.nxtbook.com/nxtbooks/macs/servicereports_2019
https://www.nxtbook.com/nxtbooks/macs/servicereports_2018
https://www.nxtbook.com/nxtbooks/macs/servicereports_2017
https://www.nxtbook.com/nxtbooks/macs/servicereports_2016
https://www.nxtbook.com/nxtbooks/macs/servicereports_2015
https://www.nxtbookmedia.com