CYLINDER AS-HYDRAULIC 6J0337 - Caterpillar

Introduction
The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.Problem
Some Engine Electronic Control Module (ECM) outputs can be damaged by short circuits in the harness or solenoid loads connected externally to the ECM. The short circuits may not have any diagnostic indication of the condition. A short circuit to block or chassis ground on the ECM outputs that control the cooling fan, the engine brakes, the coolant diverter valve, and the variable valve actuation (VVA) end of rail valve could cause these ECM outputs to fail. Refer to Table 1 for affected ECM outputs. Multiple ECM failures may occur on an engine if the short circuit in the wiring or solenoids connected to the ECM is not remedied before replacing the ECM. The ECM will not fail on these outputs unless the short circuit condition has first occurred. Note: There will not be a diagnostic code indicating the short circuit condition has or currently exists for most of these outputs.
Table 1
Engine ECM Output     Engine ECM Connector/Pin    
Cooling Fan     J1/Pin 11    
Engine Brake Low/High     J2/Pin 1    
Inlet Ar Shutoff     J2/Pin 6    
Engine Brake Med/High     J2/Pin 8    
Coolant Diverter     J2/Pin 5    
VVA EOR Valve     J2/Pin 3    
Programmable Outputs     J1/Pins 10, 12, 13, 19, 20, 21    Solution
Locate and eliminate the short circuit condition in order to avoid unnecessary multiple ECM replacements.If an ECM output listed in Table 1 has failed and no short to chassis or block was identified during the initial troubleshooting, then the short is most likely intermittent. Please perform the following checks:
Visually inspect the wiring from the ECM connector to the solenoid. Look for cuts or abrasions in the insulation that have exposed the wire. Repair as necessary.
Solenoids may experience intermittent short circuits between the coil and the case of the solenoid. With the solenoid disconnected from the circuit, measure the resistance of the solenoid conncector pins to the solenoid. If the resistance changes substantially while being exercised, replace the solenoid. Note: The vibration and temperature fluctuations due to a running engine may also cause the problem to be intermittent.