Product Manual

8
TESTING PROCEDURES
7 ROUND PIN TRAILER TESTING PROCEDURE:
MANUAL TESTING MODE
To avoid false readings:
Visually inspect trailer socket for corroded and/or squeezed pins.
Bad or broken socket pins can cause false readings. Replace socket if pins are
broken or socket appears to have been subjected to extreme heat. If con-
nections are corroded, clean all connections with the 7 Round Pin Connector
Cleaners (IPA®’s #8024) and load socket with dielectric grease.
1. Prior to any testing on the MUTT®, connect the trailer to the tester or you
will receive erroneous readings. The MUTT® is to be used while connected
ONLY.
2. To select the power source, push the Power Selection Switch (Fig. 2-H)
to the left to select the tester’s internal battery, or to the right to use an
external battery. Use supplied 5 foot Power Adapter Plug with Alligator
Clips (#7900K-93) for the external battery connection.
3. Secure 7 round cable to socket at the left side of the tester.
4. Initial power starts a test cycle through all the LEDs. This performs the
“GROUND INTEGRITY TEST”.
5. Check Voltage Indicator (Fig. 2-C) for green illumination. In the case of low
or weak supply voltage, yellow color illuminates. Red illumination from
the Voltage Indicator shows inadequate power supply. Also see warning
indicator section. (page 12)
6. Ground Integrity Check: When the SMART MUTT® is rst turned on, notice
the green lights circling the dial. This indicates the SMART MUTT® is test-
ing for ground integrity. If there is a lack of ground, all the green lights
will begin to ash. If you only see one green light ashing, this indicates
an Open Circuit (Check your 7 pin connections rst, then the trailer). If you
do not have ground integrity, the SMART MUTT® cannot continue normal
testing functions until a solid ground is established. To troubleshoot, rst
you need to understand the type of ground being used on your particular
trailer. There are two types: Some trailers are wired with each trailer light
grounded via the return wire in the in the 7 pin connector located at the
front of the trailer. On other trailers the trailer lights are directly grounded
through the trailer’s chassis.
6a. If the trailer is grounded through the plug the technician needs to locate
the source of this poor ground. Suggestion: Check the 7 way plug termi-
nals and pin connections FIRST for loose tolerance, or broken connections.