Pre-Trip Test

Run the automated pre-trip inspection on the X4 unit

Pre-Trip is a set of tests run by the APX Control System to check unit operation. Run Pre-Trip BEFORE loading the refrigerated compartment. Pre-Trip can be started at any box temperature and will run 17 tests taking approximately 7 to 15 minutes.

Unit State at Start

If Pre-Trip is started while the unit is in a Start-Stop off cycle, the unit will start during the test. If the unit is already running, it will shut down for the first three tests, then restart as it proceeds through the remaining tests.

Step 1: Access Pre-Trip Menu

With the START/RUN-OFF switch in the START/RUN position, press the MENU key until PRETRIP is displayed.

Step 2: Open Pre-Trip Screen

Press the PRETRIP soft key to display the Pre-Trip Menu screen. The screen will display with a 15-second timeout.

Step 3: Select Start Pre-Trip

Press the ▲ or ▼ key to scroll to "Start Pre-Trip", then press the "=" key to begin. The Pre-Trip Status screen will be displayed.

ALARM Light During Pre-Trip

During Pre-Trip the ALARM light will illuminate to indicate there is no temperature control. This is normal.

Viewing Unit Data

At any time during Pre-Trip, press the UNIT DATA soft key to view the Unit Data screen (Section 3.14). Press the BACK soft key to return to Pre-Trip.

Step 4: Verify Test 1 Items

During Test 1, verify that the buzzer is energized, the amber light on the light bar is illuminated (if equipped), and the AutoFresh air port opens and closes (if equipped).

Step 5: Wait for Remaining Tests

The remaining tests run automatically. A progress bar shows the percent of Pre-Trip completed under the test description.

Step 6: Review the Result

"PRETRIP PASS", "PRETRIP FAIL IN TEST ##", or "PRETRIP FAILED AND COMPLETE" will be displayed at the end. The PASS message displays until a key is pressed. The FAIL message displays until alarms are cleared.

Step 7: Review Alarms

Press the VIEW ALARMS key to move to the Alarm Screen (Section 3.15) and review any alarms activated during the test.

View Results Anytime

Press the TEST RESULTS soft key at any time during Pre-Trip to view results of completed tests. Press ▲ or ▼ to scroll through results. You can also select "View Results of Last Pre-Trip" from the Pre-Trip Menu.

Stop Pre-Trip Early

To end Pre-Trip at any time, press the STOP PRETRIP soft key.

Pre-Trip runs up to 17 tests: • Test 1 — Display Test (buzzer, light bar, AutoFresh port) • Test 2 — 12VDC Electrical Component Amperage Check • Test 3 — Temperature Sensor Check • Test 4 — Warm Up (Cool or Heat mode based on ambient) • Test 5 — UL2 (Rear) Unloader • Test 6 — UL1 (Front) Unloader • Test 7 — Engine Low Speed • Test 8 — Engine High Speed • Test 9 — Engine Low Speed 2 • Test 10 — Suction Modulation Valve (CSMV) • Test 11 — EVXV • Test 12 — SV1 • Test 13 — SV4 (skipped if ambient above 100°F / 37.8°C) • Test 14 — Low Side Pump Down • Test 15 — Pressure Hold Check • Test 16 — Discharge Check Valve • Test 17 — Check for Other Alarms

After Pre-Trip Completes

When Pre-Trip is complete, the unit returns to normal temperature control operation. Press the EXIT key to dismiss the PASS screen.

Pre-Trip Abort

Pre-Trip will run until completed unless an alarm occurs that would cause erroneous results or affect future tests. Only those alarms will abort Pre-Trip.

Alarm-Based Failure

Before completing, the APX Control System checks for active alarms such as Low Fuel Warning, Check Engine Oil Level, or Check Coolant Temperature. If present, Pre-Trip will display "FAILED" — check the alarm list and correct all alarm conditions.

Cannot Start Pre-Trip?

If "CAN NOT START PRE-TRIP" is displayed in the MessageCenter, check for: PC mode (Section 5.3.2), Defrost mode running, or active shutdown alarms in the alarm list (Section 3.15). Clear these conditions before attempting Pre-Trip again.