OM3212 08/11 Operator Cab and Controls - Section 32 Page 32-27 QUANTUM™ FUEL SYSTEM DIAGNOSTICS Determining Fault Codes Quantum™ fault codes consist of three numerical digits. Each digit is indicated with up to five light flashes (check engine monitor light) per each digit. There is a short pause between each digit of the fault code. Once all three digits are flashed, there is a lon- ger pause, followed by a repeating of the same fault code sequence. Check engine monitor light (7, Figure 32-9) monitors the Quantum™ Fuel Control System. When the key- switch is turned ON, this light should illuminate for about 2 seconds and then turn off, if no faults are detected in the system. 1.
To determine an active Quantum™ fault, turn the keyswitch to the OFF position. Be sure the engine completely stops, if it was running. 2. Turn keyswitch to ON position (engine not run- ning) and move the lamp test switch to the left (" " position) for 1 - 2 seconds, then release (switch is spring-loaded to the middle, OFF, position). If the light stays on, or flashes, then active faults have been detected by the system and the engine should not be started. Refer to Determining Fault Codes.
During engine operation, if a fault is detected in the system, the light will turn on and stay on for "warning” faults, or it will turn on and flash for more severe faults that can affect engine operation and require immediate attention. 3. If there is an active fault, after releasing the switch there will be a short pause, followed by the first fault code. "Warning" faults (light on) are ones that require attention in the near future, but in most conditions will not greatly affect governing performance. "Severe" faults (light flashing) are ones that require immediate attention, because Quantum™ governor performance could be significantly affected, resulting in a backup mode of operation.
Active fault conditions must be corrected as soon as possible. Lamp test/diagnostic test switch (14, Figure 32-9) may be used to activate the Quantum™ fuel system diagnostic codes. When the Quantum™ fuel system detects a fault and the check engine monitor light (7, Figure 32-9) illuminates as described above, this switch will allow determination of the kind of fault(s) detected.