Case IH F-153-16 - ECU – Engine Control Unit (ECU): Crankcase pressure too high

The sensor is reading a pressure inside the engine crankcase that exceeds the maximum allowable threshold, which can lead to blown seals, oil leaks, or indicate severe internal engine issues.

• MAGNUM AFS Connect
• 240 Series
• 5140
• 6140
• 6150
• 7140
• 7150
• 7240
• 7250
• 8240
• 8250
• 9240
• 9250
• 1021G
• 1121F
• 1121G
• Maxxum
• Magnum
• Steiger

1. 1

   Check for a plugged or restricted crankcase breather or filter (most common cause of high crankcase pressure)

2. 2

   Inspect the 3-pin wiring harness leading to the crankcase pressure sensor for shorts, corrosion, or an open circuit

3. 3

   Check the engine oil dipstick for an overfull level or fuel dilution (oil smells like diesel)

4. 4

   Check for a leaking intake manifold gasket forcing turbocharger boost pressure into the valve mechanism area

5. 5

   Evaluate for internal engine wear causing excessive blowby (worn cylinder bores, worn piston rings, or a cracked piston)

1. 1

   Verify the Code

   Connect a diagnostic scan tool to the machine's diagnostic port to confirm F-153-16 is active. Check for secondary codes (such as fuel pressure or oil level codes) that might point to fuel dilution.

2. 2

   Service the Breather

   Locate the crankcase breather element. Remove and inspect it. If it is saturated with oil, frozen, or clogged with debris, replace the breather filter. Clear the code and test run the engine under load.

3. 3

   Test the Sensor

   If the breather is clear, use a multimeter to test the crankcase pressure sensor's voltage output. If the sensor is sending an erratic or out-of-calibration signal to the ECU, replace the sensor.

4. 4

   Check for Leaks

   If the sensor is functioning correctly, check the oil for fuel contamination. If fuel is present, diagnose the fuel injectors and high-pressure fuel system for leaks. Change the oil and filter after repairing the leak.

5. 5

   Mechanical Testing

   If the code persists, perform a mechanical blowby test using a manometer. If blowby is excessive, inspect the intake manifold gasket for boost leaks into the crankcase. If the gasket is intact, an engine overhaul (piston rings/liners) may be required.

6. 6

   Final Validation

   Clear all fault codes from the ECU and run the machine at operating temperature to ensure the code does not return.