12000-ZW1-000ZA Honda BLOCK ASSY., CYLINDER *NH8* (Honda Code 4897278). (DARK GRAY)

The Electronic Control Module (ECM) monitors the engine oil pressure. The following event is associated with low engine oil pressure:
Table 1
Diagnostic Codes for Low Engine Oil Pressure
J1939 Code Description Information
100-1 Engine Oil Pressure : Low - most severe The ECM has been powered for at least 2 seconds.
The engine has been running for at least 60 seconds.
There are no diagnostic trouble codes for the 5 VDC supply.
The engine will be derated.
As engine oil pressure is monitored by a switch, the electronic service tool will show either 0 kPa (0 psi) or 300 kPa (43.5 psi). This indication shows that the switch is either open or closed and not actual engine oil pressure.Probable Causes
Engine oil level
Oil specification
Engine oil pressure
Engine oil filter
Engine oil cooler
Fuel in the engine oil
Engine oil suction tube
Engine oil pump
Bearing clearanceRecommended Actions
Engine Oil Level
Inspect the engine oil level. If necessary, add oil.
If the fault is still apparent, proceed to "Oil Specification".Oil Specification
Make sure that engine oil of the correct specification is used. Refer to the Operation and Maintenance Manual, "Refill Capacities and Recommendations".
If necessary, drain the oil system and refill the oil system with engine oil of the correct specification. Refer to Operation and Maintenance Manual, "Engine Oil and Filter - Change".
If the fault is still apparent, proceed to "Engine Oil Pressure".Engine Oil Pressure
Check the actual engine oil pressure with a calibrated test gauge. If normal oil pressure is seen, investigate the oil pressure switch and the associated wiring.
If low oil pressure is indicated, proceed to "Engine Oil Filter".Engine Oil Filter
Remove the engine oil filter. Refer to the Operation and Maintenance Manual, "Engine Oil and Filter - Change".
Inspect the engine oil filter for evidence of blockage.
Install a new engine oil filter. Refer to the Operation and Maintenance Manual, "Engine Oil and Filter - Change".
If the fault is still apparent, proceed to "Engine Oil Cooler".Engine Oil Cooler
If oil flow or coolant flow through the oil cooler is suspected of being low, replace the oil cooler. Refer to Disassembly and Assembly, "Engine Oil Cooler - Remove" and Disassembly and Assembly, "Engine Oil Cooler - Install".
If the fault is still apparent, proceed to "Fuel in the Engine Oil".Fuel in the Engine Oil
If contamination of the engine oil with fuel is suspected, refer to Troubleshooting, "Oil Contains Fuel".
If the fault is still apparent, proceed to "Engine Oil Suction Tube".Engine Oil Suction Tube
Check the inlet screen on the oil suction tube and remove any material that may be restricting oil flow.
Check the joints of the oil suction tube for cracks or a damaged joint. Cracks or damage may allow air leakage into the supply to the oil pump.
If no faults are found, proceed to "Engine Oil Pump".Engine Oil Pump
Inspect the components of the engine oil pump for excessive wear. Repair the oil pump or replace the oil pump, if necessary. Refer to Disassembly and Assembly, "Engine Oil Pump - Remove", Disassembly and Assembly, "Engine Oil Pump - Install" and Disassembly and Assembly, "Engine Oil Relief Valve - Remove and Install".
If no faults are found, proceed to "Bearing Clearance".Bearing Clearance
Inspect the engine components for excessive bearing clearance or damaged bearings. If necessary, replace the bearings and/or the components. Inspect the following components for excessive bearing clearance:
Crankshaft main bearings
Connecting rod bearings
Camshaft front bearing
Idler gear bearingIf the fault is still present, contact the technical communicator at a Cat® dealer.