Troubleshooting
32Fault codes
| Code | Meaning |
|---|---|
| A1 | Discharge Temp High, 239 Degrees (Warning) |
| A2 | Water Temp High, 221 Degrees (Warning) |
| A5 | Charge, Belt Loose/Bad Connection (Warning) |
| E1 | Discharge Temp, 248 Degrees (Emergency) |
| E2 | Water Temp, 230 Degrees (Emergency) |
| E3 | Engine Oil Pressure, Below 7.3 PSI (Emergency) |
| E6 | Discharge Temp Sensor Disconnected (Emergency) |
| E7 | Water Temp Sensor Disconnected (Emergency) |
Symptoms & remedies
| Symptom | Cause | Remedy |
|---|---|---|
| Unit starts and then stops, or stops when switched from "Start" to "Run" position, with NO emergency warning lights lit | Problem is in the regulation or fuel systems | See troubleshooting the regulation or fuel system |
| Warning light (hot engine coolant, hot air discharge or low engine oil pressure) does not go out; unit stops after the 8-second timer runs out | Fault in the circuit indicated by the warning light that stays on | Check that circuit |
| Unit has been operating for a period of time and cuts off | A sender circuit (hot engine coolant, hot air discharge or low engine oil pressure) is causing the shutdown | Check which warning light is staying on; if not seen, restart the unit and let it run under load until it shuts down to determine which circuit is causing the shut down |
| Unit shuts down with no warning light | Problem is in the regulation or fuel system | See troubleshooting the regulation or fuel systems |
| Hot Engine Coolant light is on | Coolant not at the proper level | Check to see if coolant is at the proper level |
| Hot Engine Coolant light is on | Fan belt not properly adjusted | Check the fan belt for proper adjustment |
| Hot Engine Coolant light is on | Coolant leaks: hoses, water pump, radiator and radiator cap sealing gasket | Inspect the unit for coolant leaks |
| Hot Engine Coolant light is on | Thermostat not operating properly | Check the thermostat for proper operation |
| Hot Engine Coolant light is on | Bubbles in the radiator; compression leaks usually will let coolant into the engine oil | Check for bubbles in the radiator |
| Hot Engine Coolant light is on | Fan, oil cooler and radiator blocked; trash passes through the oil cooler and stops up the radiator | Inspect the fan, oil cooler and radiator for blockage; you may have to remove the radiator to properly check |
| Hot Air Discharge light is on | Low oil level in compressor receiver tank | |
| Hot Air Discharge light is on | Oil with air bubbles, water mixing in oil, foaming, dark color or burnt smell | Inspect oil |
| Hot Air Discharge light is on | Wrong type of oil used, or wrong oil added to top-off oil level (different types of oils don't mix) | |
| Hot Air Discharge light is on | Compressor oil filter is restricted | Change oil and filter |
| Hot Air Discharge light is on | Oil cooler stopped up | Check oil temperature in and out of the cooler; there should be an 8 to 12 degree difference in the temperatures |
| Hot Air Discharge light is on | Thermo Bypass valve not working properly | |
| Unit cold, the hot engine coolant light or hot air discharge light stays on | Hot engine coolant sender reads "open" | Check wires for loose connections; unplug the two wires and use the Ohmmeter to check the switch (it should be closed, reading maximum Ohms); if the sender reads "open" it should be replaced |
| Unit cold, the hot engine coolant light or hot air discharge light stays on | Hot air discharge sender reads "open" | Test sender same as the hot engine coolant sender; if it reads "open" it should be replaced |
| Unit cold, the hot engine coolant light or hot air discharge light stays on | Blown fuse in the fuse/relay box at the rear of the compressor | Remove the fuse box cover located on the side of the fuse/relay box and inspect the fuses; replace as needed |
| Faulty reading when testing relays and diodes | Loose or corroded wire connections | Always check wires for loose or corroded connections |
| Relay suspected bad in the emergency stop circuit | Defective relay | Swap it with another relay in the emergency stop circuit to see if the problem changes to the other circuit; to test, remove it from the circuit, use two jumper wires to connect the relay to a power source (positive lead to #1 terminal, ground to #2 terminal) and you should feel or hear the relay click; if not, hook the Ohmmeter across terminal #3 and terminal #5 and you should get a continuity reading; if not, check terminals #3 and #6 — if you get a reading here the relay is bad |
| Low engine oil pressure circuit problem | Engine oil level or condition of the oil and filter | Check engine oil level and condition of the oil and filter |
| Low engine oil pressure circuit problem | Oil pressure | Remove the sender and hook-up a 150 psi gauge to check oil pressure |
| Low engine oil pressure light will not glow when the starter switch is turned on | Low engine oil pressure sender not functioning correctly | Replace the sender; if the sender is not working properly, the circuit will not shut down the engine if oil pressure is low |
Fault codes and symptom→remedy steps extracted from this unit’s service/owner documentation; verify against the official manual before servicing.
Available documents
Service manual
About
Allmand T4 — light tower. Specifications and parts compiled from manufacturer documents.