Mac 600 with 4 Stars

[WaveformSound]

Hey Guys,

 

I have a Mac 600 that is having a bad day, well many now. On power on the display holds on the 4 stars continuously. On power on the lamp strikes on straight away and nothing else happens. Ive exchanged the display board from a good 600 along with the cable. Ive checked the pins in the ribbon connector and all are fine. This problem travels with the main PCB board from mac to mac. I did get it to power on and home through as normal only once. All 3 fuses are fine and are making contact.

 

Is there anywhere else I can investigate or areas ive not touched yet?

 

Many Thanks

[johnhuson]

Have you tried re-flashing the software? To do this you'll need one of the many incarnations of the Martin Software Uploader. If you don't have the capabilities to do this it's worth asking around a few local hire companies as there is a good chance at least one of them will have one.

 

Failing that I can highly recommend The Lighting Hospital for PCB level repairs.

[stuart.thompson]

I would also say the PCB has lost its firmware and needs the software re uploading..... This will need to be done in boot mode too as the unit will not reset. Details to do that is found in the MAC 600 manual. You will need one if the martin interfaces compatible with uploading software.

[bigclive]

If it did home once then there's a chance that the processor is not getting through a self test at power-up. The fact it's displaying four stars may suggest that the processor is running, but there are issues on the card, either soldering or component failure.

[gyro_gearloose]

The usual boot up sequence for Macs of that age is a row of four stars on the display, then the fixture type (Mac 500, Mac 600, etc), then the version of the firmware. Since the OP is only seeing four stars then there is something major wrong with the main board. The display board has a separate cpu of its own so even though there's something shown on the display, the main board isn't communicating with the display board.

 

The first thing to check would be the power supply section of the PCB. There should be several LEDs in a row which indicate the presence (or not) of various voltages that the motors, driver chips, logic, etc need in order to work. If any or all of these LEDs aren't lit then the OPs fault lies somewhere within the power supply, but since the display board works, then there may be something else wrong with the main board.