Case IH 2905 – TCU (Transmission Control Unit) or UCM (Universal Control Module): Solenoid F1 Shorted High / Transmission Range Clutch C7 Solenoid

The service brake pressure transducer is shorted to power (signal above 4.75 V for > 500 ms). Note: According to documentation, fault code 2905 is actually defined as Solenoid F1 Shorted High or Transmission Range Clutch C7 Solenoid, while the brake pressure transducer short is officially code 2549.

• Steiger T4B
• Case IH Puma series (165, 180, 195, 210, 225 CVX)
• Case IH Maxxum 140

1. 1

   Inspect the brake pressure transducer connector (e.g., connector X-549) and the UCM connector (e.g., X-953). Ensure the connectors are fully seated, not damaged, and that the pins are tight and free of corrosion.

2. 2

   Disconnect the transducer connector, turn the ignition switch to the ON position, and measure the voltage to check for a +5 Volt reference.

3. 3

   Backprobe the sensor connector to confirm the 5V reference and ground continuity, and verify that the signal wire is not shorted to power or ground.

4. 4

   Monitor the sensor output with a Digital Volt-Ohm Meter (DVOM) or oscilloscope while operating the brake system to see if the output changes smoothly and stays within the expected voltage range.

1. 1

   Replace transducer if failed

   If the diagnostic checks reveal that the wiring and connectors are intact but the signal remains shorted or stuck, the transducer itself has failed and must be replaced.

2. 2

   Disconnect electrical connector

   Disconnect the electrical connector at the brake pressure transducer.

3. 3

   Remove faulty transducer

   Remove the faulty brake pressure transducer from the hydraulic port.

4. 4

   Install new transducer

   Install the new brake pressure transducer and reconnect the electrical harness.

5. 5

   Replace connector housing

   If the connector housing is damaged and causing the short, replace the connector housing and pins.

6. 6

   Clear fault codes and verify

   Clear the fault codes and operate the brake pedal to verify the sensor output is now within the normal range.