New Holland IC 1004 – IC: Hydraulic Oil Filter Restricted

This code indicates that the hydraulic filter restriction switch has detected a pressure differential that exceeds normal operating limits, meaning the hydraulic oil filter is blocked or severely restricted. This prevents proper hydraulic fluid flow and can allow contaminants to bypass the filter and circulate through expensive pumps and valves.

• L218
• L220
• L316
• L318
• L320
• SR175
• C175
• C185
• C190
• L140-L185
• LS140-LS190 series
• LX465-LX985 series
• FR9040
• FR9050
• FR9060
• FR9080
• FR9090
• TS series
• 4060TS series

1. 1

   Ensure the hydraulic oil is up to normal operating temperature. Cold, thick hydraulic oil can cause a temporary high-pressure differential that triggers a false restriction warning.

2. 2

   Inspect the wiring harness leading to the hydraulic filter restriction switch. Look for open circuits, shorts to ground, or shorts to power.

3. 3

   Check the switch connectors for corrosion or loose pins, as agricultural environments can degrade the weatherproof seals and cause intermittent signal faults.

1. 1

   Relieve Pressure & Drain

   Ensure the machine is off, attachments are lowered to the ground, and hydraulic pressure is relieved.

2. 2

   Replace the Hydraulic Oil Filter

   The primary fix for this code is to remove and replace the clogged hydraulic oil filter.

3. 3

   Test the System

   Run the machine to operating temperature. If the IC 1004 code clears and the dash warning light goes out, the repair is complete.

4. 4

   Replace the Restriction Switch

   If a new filter does not clear the code, the restriction switch itself has likely failed. Disconnect the battery, take a photo of the wire positions (as some switches have multiple terminals), and unthread the old switch.

5. 5

   Install New Switch

   Thread in the new hydraulic oil pressure/restriction switch, reconnect the wiring harness, and clear the fault codes using a diagnostic tool.