Section 7 - Alarm Troubleshooting; Introduction; Notes - Carrier VECTOR 1550 Series Operation & Service Manual

WARNING
LogiCOLD microprocessor equipped units
may start automatically at any time the
START/RUN-OFF switch (SROS) is not in
the OFF position. Also, the unit may be fit-
ted with two way communication equip-
ment that will allow stating of the unit from
a remote location even though the SROS is
in the off position.
WARNING
Be aware of HIGH VOLTAGE supplied at
the power plug or from the generator.
When performing service or maintenance
procedures: ensure any two way commu-
nication is disabled in accordance with the
manufacturers instruction,
START/RUN-OFF switch is in the OFF posi-
tion and, whenever practical, disconnect
the high voltage source and disconnect the
negative battery connection. NEVER dis-
assemble the generator: HIGH MAGNETIC
FIELD INSIDE! This field can interfere with
cardiac implants such as pacemakers and
defibrillators.
7.1

INTRODUCTION

This section provides guidance for troubleshooting
alarms. The alarm light will be illuminated when there
is one (or more) alarm(s) stored in the microprocessor.
Instructions for reviewing the alarm lists are provided
in sections 3.11 & 3.12.
When an alarm occurs, look through both Active and
Inactive alarm lists in the microprocessor and make
note of all alarms. Each alarm begins with an A (ac-
tive) or I (inactive) followed by an alarm number and
description. Alarms are listed in this guide by alarm
number in ascending order.
Before beginning to actually troubleshoot an alarm,
visually inspect the unit, in particular the area of the
unit that is causing a problem. In many cases the
cause of the problem will be obvious once a visual
inspection is performed. For those cases where the
cause of the problem is not obvious, this troubleshoot-
ing guide will be of assistance.
Troubleshooting should begin with the first alarm that
appears in the active alarm list. The first alarm that
appears is the last alarm that was recorded. Other
alarms in the list may have contributed to the occur-
rence of the first alarm.
The check items in the troubleshooting guide are listed
in order of their likeliness of occurrence and ease of
testing.
SECTION 7 -
ALARM TROUBLESHOOTING
We recommend that you follow the order in which they
are presented; however, there may be times when
situations or experience lead a to the use of a different
order. For example, if the trailer is loaded, condensing
unit checks should be done first, even though some
evaporator section checks may be listed before them.
When the cause of the problem is corrected, it is not
necessary to continue through the remainder of
the steps. Some active alarms will inactivate them-
selves automatically once the cause has been correct-
ed. Alarms that do not inactivate themselves automati-
cally must be cleared manually. (Refer to Note 1, Sec-
tion 7.2)
When repairs are completed, run the unit through a
Pretrip cycle and verify that no further active alarms
occur. Also, the inactive alarm list should be cleared
so that there are no 'old' alarms in memory when the
unit leaves the repair facility.
If the message CHECK MICROPROCESSOR or
ensure the
CHK WIRES FROM MICRO TO KEYPAD appears in
the MessageCenter, there is a communication error
between the keypad and the microprocessor. With no
communication, there will not be an associated alarm.
Should this occur, check the wire connections behind
the keypad assembly, at the keypad itself (remove the
rear cover to check), and at connector 5MP on the
microprocessor. Check for microprocessor status led
blinking at 1 second rate (1 second ON/1 second
OFF).
When working on the refrigeration system, an accu-
rately calibrated manifold test set should always be
installed. It is not necessary to connect an additional
high pressure gauge at the liquid line service valve.
The MessageCenter, under DATA, will display com-
pressor suction pressure, compressor discharge pres-
sure and evaporator outlet pressure.
In high or low ambients it may be necessary to cool or
warm the refrigerated compartment temperature be-
fore performing specific tests providing that the com-
partment is not loaded with perishable product.
7.2
Note 1
7-1

NOTES

The active alarm list may be cleared by
scrolling to the end of the list. "LIST END, =
TO CLEAR ALARMS" will appear in the
MessageCenter. Pressing = will inactivate
the alarms. That is: the alarm is "cleared"
from the active alarm list and moved to the
inactive alarm list for later review if the condi-
tion that caused the alarm has been correct-
ed. When Shutdown Alarms are cleared, the
unit will attempt to restart. When non-
Shutdown Alarms are cleared, there will be
no noticeable change in the unit's operation.
62-61753-21