Display Panel Microprocessor No.

The standard instrument cluster contains a microprocessor. The instrument panel cluster (IPC) microprocessor communicates with other controllers in the vehicle over the Class 2 serial data bus. The information passed over the Class 2 bus, along with direct external connections to other controllers and devices provides the inputs that are used to operate all of the gauges and the illuminated displays in the cluster. Some displays and gauges are operated directly by external sources (devices or controllers) and others are under software control of the IPC. As the IPC microprocessor runs the operating software, the microprocessor continuously processes Class 2 data in order to determine the correct values and states to display.


PRNDL Indicator (Park Reverse Neutral Drive Low)
The PRNDL display is a variable function electronic display located in the IPC. The PRNDL display is capable of displaying PRND321. The display electronically illuminates, or lights the back of the desired character in order to indicate the gear selection in the transmission. The IPC controls the PRNDL by use of the Class 2 messages that are received from the PCM/VCM. The vehicles with automatic transmissions have an electronic park reverse neutral drive low (PRNDL) range indicator. The system uses the signals from the neutral safety back up (NSBU) switch on the side of the transmission. Signals from this switch determine which LED is in the electronic PRNDL will light. The system is electronic. No internal adjustment is needed. Refer to Transmission/Transaxle for diagnostic information.

n very rare instances, the AVR-5805 internal microprocessor might lock up, or otherwise cause mis-operation. This might be caused due to an AC line surge or line spike noise, or by static electric discharge on or nearby the unit, or to connected components. If the condition cannot be corrected by powering off the unit, including disconnection of the AC cord for a period of ten minutes and subsequent re-connection, then the unit may have to be re-initialized. Doing so will restore the microprocessor to its original out-of-the-box state, with all custom memories and settings erased, and the original factory default settings restored. Only use this procedure if you are sure that the microprocessor requires re-initialization.
1 Switch off the unit using the Main unit's power operation
switch.
2 Hold the following STANDARD button and HOME THX
CINEMA button, and turn the Main unit's power operation
switch on.
3 Check that the entire display is flashing with an interval of
about 1 second, and release your fingers from the 2 buttons
and the microprocessor will be initialized.
NOTES:
If step 3 does not work, start over from step 1.
If the microprocessor has been reset, all the settings are reset
to the default values (the values set upon shipment from the
factory).

There are, at the very least, a few different types of protection, DC Offset, Thermal Overload, or simply a voltage from a sensor transistor to the microprocessor IC,(display microprocessor) that communicates with the main microprocessor IC, one of the computers in your unit) to open the AC relay. If require more assistance, or would like to inquire about repairing your unit, please visit my website at audioserviceclinic.com. Thank you.

Could be a number of problems...first of all, if you have no display, then it may be the low voltage power supply has gone bad....if you do have display, then either vthe keypad has gone bad or the microprocessor inside has gone bad.

I have the same problem. I think it may be the microprocessor unit - fist check no errors come up on the display and that the lint filter is clean. The microprocessor is very expensive and I am considering buying a new machine due to the prohibitive cost of spare parts. The only other option would be to get a second hand unit and take out the processor unit from there and swap it with the ? faulty unit.

14 INITIALIZATION OF THE MICROPROCESSOR
When the indication of the display is not normal or when the operation of the unit does not shows the reasonable result, the initialization of the
microprocessor is required by the following procedure.
1 Switch off the unit and remove the AC cord from the wall
outlet.
2 Hold the following AUTO button and PCM button, and plug
the AC cord into the outlet.
3 Check that the entire display is flashing with an interval of
about 1 second, and release your fingers from the 2 buttons
and the microprocessor will be initialized.
NOTES:
• If step 3 does not work, start over from step 1.
• If the microprocessor has been reset, all the button settings are
reset to the default values (the values set upon shipment from
the factory).
• Calling out preset stations from the main unit‘s panel.
1 Press the TUNING PRESET button. TUNING
PRESET
FUNCTION 2 Turn the FUNCTION knob and
select the desired station.
TV CD CDR/MD/TAPE RECEIVER
VCR DBS/CABLE
SKIP
SKIP
ENTER
MEMORY
CHANNEL VOLUME
+
-
+
-
VDP DVD
TUNER PHONO CD
DISPLAY
SETUP RETURN
MENU
SHIFT
SURR.
PARA. OSD
A/B
MUTING
BAND MODE
TUNING
TUNING
2 1
(Main unit)

Sounds like a surge on the power line if the low voltage transformer was opened up, especially if you had a shorted zener.

There may be a voltage regulator bad (5V regulator) or the microprocessor may be bad. Often a blown microprocessor will look like this:



If the microprocessor is bad, it's best to replace the whole boar dif you can get it economically.

Feel free to contact me directly with your brand, full model number, FCC ID number, and remind me of the symptoms. I may have some service data on it and might be able to help.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

William E. Miller
[email protected]
http://www.microwavedisplay.com
Microwave Oven Control Panel Repair Nationwide

Your unit has a hard short in it. This is usually a power supply problem. Most likely the rectifier has failed. This should be a relatively simple and inexpensive repair. Figure on $10 for parts plus the local labor rate.

Dan

I repair alot of flat panel TVs and whenever you're dealing with a problem with OSD (on screen display) That means that the microprocessor circuit is having a problem. The microprocessor is always found on the main board of these units. So I suggest you take it to an authorized Sony repair shop to be checked out.


C-Dog

This does sound like a uP (Microprocessor) problem... If you don't know what a microprocessor is or how to troubleshoot the problem, your best bet is to cut your losses and take the set to a repair shop. In addition to the possibility of a microprocessor the easiest thing to check for would be to actually check the wiring... Sorry i cant help you more...