Case IH 3088 – Engine Electronic Control Unit (ECU) / ECU A-095: Crankshaft speed sensor values are not plausible.

This fault indicates a discrepancy in the engine timing signals. The ECU logs this fault if the camshaft speed sensor signal is plausible, but a crankshaft speed signal is not detected for at least two camshaft revolutions (or the pattern is invalid).

• Steiger T4B
• Puma Series (165, 180, 195, 210, 225 CVX)
• Magnum Series (180, 190, 200, 210, 220, 225, 240)
• Farmall Series (40, 45, 50)
• 240 Series Axial-Flow Combines
• Farmlift Series (632, 635, 735, 742)

1. 1

   Verify that the tractor's battery power supply has not been connected to an external power supply (e.g., a jump starter or external charger), as voltage irregularities can cause sensor plausibility faults.

2. 2

   Visually inspect the relevant harnesses and connectors leading to the crankshaft speed sensor for physical damage, bent or dislocated pins, corroded terminals, or broken wires.

3. 3

   Verify that the sensor connectors are fully installed and seated properly. Flex the wiring harness gently to check for intermittent connection issues.

1. 1

   Resolve External Factors

   If an external power supply was connected, remove it, clear the codes, and run the machine to see if the fault returns.

2. 2

   Repair Wiring

   If the visual inspection reveals damaged wires, corroded terminals, or bent pins at the sensor connector or the ECU A-095 harness, repair or replace the affected wiring.

3. 3

   Replace the Sensor

   If the wiring and connectors are in good condition but the fault persists, the electromagnetic crankshaft speed sensor has likely failed internally and must be replaced. Unbolt the old sensor, disconnect the 3-pin sealed electrical plug, and install the new sensor.

4. 4

   Software Check / Re-flash

   If the fault has still not been resolved after replacing the sensor and verifying the wiring, check the ECU A-095 for the appropriate software version. Re-flash the ECU with the latest software if necessary.

5. 5

   Return to Service

   Once the fault is resolved and the code is cleared, return the machine to service.