PLATE GP-COVER 1946656 - Caterpillar

Introduction
The problem that is identified below does not have a known permanent solution. Until a permanent solution is known, use the solution that is identified below.Problem
The 221-3405 Pressure Sensor Gp on the brake accumulator on F-series Off-Highway Trucks can develop an offset. The offset does not report any fault codes but does affect the charging function on the accumulators.Solution
At 250 hour service intervals, use VIMS Advisor display (in cab) or Caterpillar ET (laptop) to check the pressure outputs of the service brake accumulator pressure sensor, secondary brake accumulator pressure sensor and brake pump pressure sensor. Begin by shutting down unit using the key in the cab (using the ground level shutdown will retain pressure in the brake accumulators). Check the pressure outputs with the machine keyed on and engine not running, being certain the brake accumulators are fully drained. The pressure sensors should read 2345 kPa (340 psi) of absolute. If the sensor reading is out of range, the sensor should be removed and replaced with a new sensor of the same part number.