Alarm Types

There are four types of alarms.

Log Alarms

Log Alarms are indicated for 30 seconds each time the unit is turned on. This level of alarm serves as a notice to take corrective action before a problem becomes severe. Maintenance items such as maintenance hourmeter time-outs are Log Alarms. The TemperatureWatch™ screen is not disabled if only Log Alarm(s) are active.

When the unit is turned on, the display will show the Thermo King Logo and then the Configuring System message. If Log Alarm(s) are present, the Log Alarm notice will appear on the display for 30 seconds. The remote indicator alarm light (if installed) will also be on during this period. After 30 seconds, the Standard Display will appear and the remote indicator alarm light will go off.

Note The Alarm Icon does not appear on startup with Log Alarms present.

Log Alarms Screen

Check Alarms

Check Alarms are indicated by a steady alarm indication at the top of the display and the message Service Required within 24 Hours. The Alarm Icon will appear. This level of alarm serves as a notice to take corrective action before a problem becomes severe. The unit will run with Check Alarms but some features and functions may be inhibited. The TemperatureWatch screen is disabled if a Check Alarm is active.

Alarm Display

Prevent Alarms

Prevent Alarms are indicated by a steady alarm indication at the top of the display and the message Service Required within 24 Hours. The Alarm Icon will appear. The unit will be temporarily shut down if a Prevent Alarm is active. The unit will remain shut down for a timed restart interval or until the fault conditions are corrected and then restart. If the unit is in a temporary shutdown, Alarm Code 84 Restart Null will be present along with the associated Prevent Alarm. In most cases, the unit will restart with reduced performance to determine if continued operation is possible. If the alarm does not reoccur with reduced performance, the unit will return to full performance. If the unit is operating with reduced performance, Alarm Code 85 Forced Unit Operation will also be present under some conditions. In general, if the alarm condition reoccurs a defined number of times, the alarm is set as a Shutdown Alarm and no further restarts are possible. The TemperatureWatch screen is disabled if a prevent alarm is active.

Note If the Restart After Shutdown feature in the Guarded Access Menu is set for CONTINUOUS, an unlimited number of restart attempts are allowed.

Shutdown Alarms

Depending on software revisions, Shutdown Alarms may be indicated by the following:

  • The Alarm Icon will appear.

  • The display and backlight will flash on and off.

  • The display will switch from normal to inverted and back (light areas become dark and dark areas become light).

Shutdown Alarms will force the unit into shutdown. The unit will remain in shutdown until the Shutdown Alarm is manually cleared. Exceptions are some engine and electric Shutdown Alarms that become Log Alarms when switched to the alternate operating mode (diesel to electric or electric to diesel). The TemperatureWatch screen is disabled if a unit level Shutdown Alarm is active.

Shutdown Alarm Display

Pretrip Alarm Codes

If an alarm occurs during a Pretrip Test the alarm code will be displayed as Pretrip Alarm XX, where XX is the alarm code.