HP 450c Service Manual - Page 40

Service Mode 1 Service Mode 1 contains tests that do not need a complete initialization of the Printer. This means if there is a system error in normal mode, it is still possible to enter into Service Mode 1. Also, the Sensors are disabled in Service Mode 1, which means it will not be possible to load media. The only time that the sensors will be functional is during the Sensors Test. THE COVER SENSOR IS DISABLED WHEN IN SERVICE MODE 1. IF THE CARRIAGE IS MOVING IT WILL NOT STOP IF THE COVER IS OPENED. BE VERY CAREFUL NOT TO PUT YOUR HANDS INSIDE. Some of the tests in service mode 1 send test information to the printer's serial port. To view the information perform the procedure on page 4Ć7. The Electronics Test is continuously done in the background during Service Mode 1. If you are viewing information via the serial port, you will see output similar to the following: Test Mode EE test: 0 Test Mode EE test: 1 ........... Stopping a Test The service tests are continuously repeated until you stop them. To exit a test, press the Cancel and Media Source keys (some tests may take a short while before exiting). To exit Service Mode 1, you must power OFF the Printer. Entering Service Mode 1 1 While holding the Reprint key down, switch the Printer ON. 2 Once the the LEDs begin to light up one by one, release the Reprint key. The printer performs the electrical powerĆon tests and then the fan turns on and remains on. All LEDs remain off for a few seconds. Then, all LEDs begin to flash, waiting for you to perform a test. If there are any system failures during Service Mode 1 initialization, the Sheet LED (LED O) will be lit. This failure means that the Electronics Module has failed and needs to be replaced. Reprint SERVICE MODE 1 + 4-6 HP DesignJet 430, 450C and 455CA Printers Service Tests