HP Designjet 250c Service Manual - Page 174

330 350C Carriage Test for the DesignJet 330 and 350C This tests the operation of the carriage sensor and the connection between the carriage flex circuit and the cartridges. 1 Position the sensor over a white surface. (Simply place a piece of white paper under the sensor.) 2 In service mode 1, press Carriage Test. The plotter varies the LED intensity between 255 and 0. The plotter tests the connection between the carriage flex circuit and the cartridges by getting the cartridge identification and checking the electrical continuity for all nozzles. Carriage Test The plotter also tests the encoder sensor. Because the encoder sensor only detects motion, it is necessary to manually move the carriage along the encoder strip to correctly perform the test. Status. During the test, the Load Media, Error and Normal LEDs turn on (steady) if the carriage test has not found an error. If the test fails, one, two or all of these LEDs flash as indicated below: All OK Optical Sensor Failed Flex-Circuit Connection Failed Encoder Sensor Failed All Failed Output to the Serial Port (Viewing Output ' 8-36) In order to send output to the serial port, it is necessary to set the Verbose mode ON. This can be done using the iverbose 1;i underware. Error code: If an error has occurred in the sensor test, this code specifies more precisely what has gone wrong. Include this information in the report to your HP Response Center, if the problem cannot be fixed. Pen 0 = Cyan; Pen 1 = Magenta; Pen 2 = Yellow; Pen 3 = Black. Sensor sensitivity: The sensitivity measured during the test. The figures should vary from 255 to 0. Failure occurs when the sensitivity does not vary (for example, it stays at 255). Pen ID: If a pen does not fail, the plotter outputs the pen ID. 3 The test continuously repeats itself until you Shift press the Shift key. 8Ć40 Troubleshooting C4699Ć90000