GEAR-CAMSHAFT 8N8254 - Caterpillar

System Operation Description:Use this procedure in order to troubleshoot the ether system or use this procedure if any one of the diagnostic codes in Table 1 is active or easily repeated.
Table 1
Diagnostic Codes Table
Description Conditions which Generate this Code System Response
545-5 Ether Start Relay open/short to +batt The Electronic Control Module (ECM) detects an open circuit or a short to the +Battery. The ECM can only detect this condition when the ether start relay is not energized.
The ECM has been powered for at least two seconds. The code is logged.
Ether injection is disabled.
545-6 Ether Start Relay short to ground The ECM detects a short circuit to ground at the output to the ether start relay. The ECM can only detect this condition when the ether start relay is energized.
The ECM has been powered for at least two seconds.
546-5 Ether Hold Relay open/short to ground The ECM detects a short circuit to ground at the output to the ether hold relay. The ECM can only detect this condition when the ether hold relay is not energized.
The ECM has been powered for at least two seconds. The code is logged.
Ether injection is disabled.
546-6 Ether Hold Relay short to +batt The ECM detects an open circuit and/or a short to the +Battery at the output to the ether hold relay. The ECM can only detect this condition when the ether hold relay is energized.
The ECM has been powered for at least two seconds. The engine uses an ether system to improve starting in cold temperatures. The duration of the ether cycle is based on the engine coolant temperature. The ECM, which controls the ether system, uses the engine coolant temperature sensor to detect engine temperature. The ECM determines if ether should be injected by monitoring actual engine rpm and the engine temperature. The ECM will activate the ether solenoid if the engine coolant temperature is below a set temperature and the engine rpm is below a certain level. The ether will activate for a minimum of 15 seconds at 30 °C (86 °F) up to a maximum of 130 seconds at −50 °C (−58 °F). The automatic ether injection system is disabled whenever engine rpm exceeds 400 rpm or the engine coolant temperature exceeds 30 °C (86 °F).The ether injection system can also be operated in manual mode. The ether system is switched into manual mode whenever the starting aid switch is depressed. Manual mode allows ether to be injected whenever the coolant temperature is less than 30 °C (86 °F) and engine rpm is greater than 50 rpm. The manual mode will allow ether to be injected for a maximum of 130 seconds when the switch is toggled.Two driver outputs from the ECM are used to activate the ether injection system. A sourcing driver provides the voltage to the coil of the ether start relay. The other terminal of the ether start relay is connected to the digital return. A sinking driver connects to the coil of the ether hold