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+B overcurrent

2 times

Vertical deflection stopped

4 times

White balance failure

5 times

*One flash count is not used for self-diagnostic.

Turn off the power switch on the TV main unit or unplug the power cord from the outlet to stop the STANDBY/TIMER LED from
flashing.

For errors with symptoms such as “power sometimes shuts off” or “screen sometimes goes out” that cannot be confirmed, it is
possible to bring up past occurrences of failure on the screen for confirmation.

In standby mode, press buttons on the Remote Commander sequentially, in rapid succession, as shown below:

Display

Channel 5

Sound volume

Note that this differs from entering the service mode (sound volume 

).

Power ON

+

STANDBY/TIMER LED

Since the diagnostic results displayed on the screen are not automatically cleared, always check the self-diagnostic screen during
repairs. When you have completed the repairs, clear the result display to “0”.

Unless the result display is cleared to “0”, the self-diagnostic function will not be able to detect subsequent faults after completion
of the repairs.

Clearing the Result Display
To clear the result display to “0”, press buttons on the Remote Commander sequentially when the diagnostic screen is displayed,
as shown below:

ENTER

Channel 8

Quitting the Self-Diagnostic Screen
To quit the entire self-diagnostic screen, turn off the power switch on the Remote Commander or the main unit.

IC301

Y/CHROMA JUNGLE

IC541

V. OUT

IC001

SYSTEM

IC003

MEMORY

IK IN

FROM

CRT

21

HP/PROTECT

SDA

FROM

IC521

PIN 7

18

35

IO-SDAT

O-LED

37

REF

3

I-PROT

IO-BDAT

17

36

B-DAT

5

18

DISPLAY

Occurs when an overcurrent on the +B (115V) line is detected by pin 18 of IC301. If the voltage
of pin 18 of IC301 is less than 1V when V.SYNC is more than seven verticals in a period, the
unit will automatically turn off.

Occurs when an absence of the vertical deflection pulse is detected by pin 17 of IC001. Power
supply will shut down when waveform interval exceeds 2 seconds.

If the RGB levels* do not balance within 2 seconds after the power is turned on, this error will be
detected by IC301. TV will stay on, but there will be no picture.

*(Refers to the RGB levels of the AKB detection Ref pulse that detects 1K.)

After correcting the original service problem, perform the
following safety checks before releasing the set to the
customer:

1. Check the area of your repair for unsoldered or poorly

soldered connections. Check the entire board surface
for solder splashes and bridges.

2. Check the interboard wiring to ensure that no wires

are “pinched” or touching high-wattage resistors.

3. Check that all control knobs, shields, covers, ground

straps, and mounting hardware have been replaced.
Be absolutely certain that you have replaced all the
insulators.

4. Look for unauthorized replacement parts, particularly

transistors, that were installed during a previous
repair. Point them out to the customer and
recommend their replacement.

5. Look for parts which, though functioning, show

obvious signs of deterioration. Point them out to the
customer and recommend their replacement.

6. Check the line cords for cracks and abrasion.

Recommend the replacement of any such line cord
to the customer.

7. Check the B+ and HV to see if they are specified

values. Make sure your instruments are accurate;
be suspicious of your HV meter if sets always have
low HV.

8. Check the antenna terminals, metal trim, “metallized”

knobs, screws, and all other exposed metal parts for
AC leakage. Check leakage as described below.

The AC leakage from any exposed metal part to earth
ground and from all exposed metal parts to any exposed
metal part having a return to chassis, must not exceed
0.5 mA (500 microampere). Leakage current can be
measured by any one of three methods.

1. A commercial leakage tester, such as the Simpson

229 or RCA WT-540A. Follow the manufacturers'
instructions to use these instructions.

2. A battery-operated AC milliammeter. The Data

Precision 245 digital multimeter is suitable for this job.

3. Measuring the voltage drop across a resistor by

means of a VOM or battery-operated AC voltmeter.
The “limit” indication is 0.75 V, so analog meters must
have an accurate low voltage scale. The Simpson’s
250 and Sanwa SH-63Trd are examples of passive
VOMs that are suitable. Nearly all battery-operated
digital multimeters that have a 2 VAC range are
suitable (see Figure A).

A cold-water pipe is a guaranteed earth ground; the cover-
plate retaining screw on most AC outlet boxes is also at
earth ground. If the retaining screw is to be used as your
earth ground, verify that it is at ground by measuring the
resistance between it and a cold-water pipe with an
ohmmeter. The reading should be zero ohms. If a cold-
water pipe is not accessible, connect a 60- to 100-watt
trouble light (not a neon lamp) between the hot side of the
receptacle and the retaining screw. Try both slots, if
necessary, to locate the hot side on the line; the lamp
should light at normal brilliance if the screw is at ground
potential (see Figure B).

To Exposed Metal
Parts on Set

Earth Ground

AC
Voltmeter
(0.75 V)

Trouble Light

AC Outlet Box

Ohmmeter

Cold-water Pipe

The following are partial abstracts from the Operating Instruction
Manual. The page numbers shown reflect those of the Operating
Instruction Manual.

This section covers basic connections in addition to any optional 
equipment you may be connecting.

Depending on the cable available in your home, choose one of the 
connections below:

If your cable provider does not feature local channels, you may find this 
set up convenient.

✍

If you are connecting to an indoor or outdoor antenna, it will be necessary to 
adjust the orientation of the antenna for best reception. 

✍

Select CABLE or ANT mode by pressing 

 on the remote control.

 User Guide

Connect the coaxial cable from your TV antenna or cable TV to the IN 
jack on your VCR.

Connect a coaxial cable (not supplied) from the OUT jack on your 
VCR to the VHF/UHF IN jack on the TV.

If your VCR is equipped with video inputs, for better picture quality 
you should connect A/V cables to AUDIO and VIDEO OUT on your 
VCR to AUDIO/VIDEO IN on your TV. You can use the 

 button 

to switch between the TV and VCR inputs.

VCR must be connected and turned on to operate PIP. (KV-27S46 only)

✍

To watch video programs from your VCR, tune your TV to channel 3 or 4 (as 
set on the rear of your VCR).

✍

For optimum picture quality, use S VIDEO instead of the yellow A/V cable. 
S VIDEO does not provide sound, the audio cables must still be connected.

 Connecting Your TV

Connect the coaxial cable from the wall to the IN jack on your cable 
box.

Connect a coaxial cable (not supplied) from the OUT jack on your 
cable box to the VHF/UHF IN jack on the TV.

✍

To view channels from your cable box, tune your TV to channel 3 or 4 (as set 
on the rear panel of your cable box).

✍

If you will be controlling all channel selection through your cable box, you 
should consider using the CHANNEL FIX feature on page 24.

 User Guide

For this set up, you can switch between scrambled channels (through 
your cable box), and normal (CATV) channels by pressing 

 on your 

remote control.

✍

When using PIP, the AUX input cannot be viewed in the window picture.