OM3223 Operation - Section 32 Operator Cab and Controls Page 32-25 CENTRY™ FUEL SYSTEM DIAGNOSTICS If the truck is equipped with a Komatsu engine and Centry™ Fuel Control system, service engine indica- tor light (D6, Figure 32-12) monitors the Centry™ fuel system. When the key switch is turned ON, this light should illuminate for about two seconds and then turn off, if no faults are detected in the system. 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 below.
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. 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 Centry™ 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 (10, Figure 32-7) may be used to activate the Centry Fuel System diagnostic codes. When the Centry fuel system detects a fault and the serv indicator light (D6, Figure 32-12) illuminates as described above, this switch will permit determination of the kind of fault(s) detected. DETERMINING FAULT CODES Centry™ fault codes consist of three numerical digits. Each digit is indicated with up to five light flashes (service engine indicator 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 longer pause, followed by a repeating of the same fault code sequence. 1.
To determine an active Centry™ fault, turn the key switch to the OFF position. Ensure the engine completely stops.