Basic HTML Version
NOTE
CPU LED Indicator Codes Table
Blinks'
CPU Problem
ExplanatIon
Flashes
1
U25 RAM FAILU RE U25 RAM could not be used properly (NO other tests are performed;
the game Is locked here, until the game Is turned off).
2
MEM. PROT. FAILURE This message means that (A) the Coin Door may be shut; (8) the Mem-
ory Protect Switch may be stuck In the ON position; (C) the memory
protect logic Is protecting the memory; or (D) a U25 RAM failure Is
occurrtnq, (See Note 1)
3
US1 PIA FAILURE
U51 has a malfunction . (See Note 2)
4
U38 PIA FAILURE
U38 has a malfunction.
(See Note 2)
5
U41 PIA FAILURE
U41 has a malfunction.
(See Note 2)
6
U42 PIA FAILURE
U42 has a malfunction.
(See Note 2)
7
US4 PIA FAILURE
U54 has a malfunction.
(See Note 2)
8
U10 PIA FAILURE
U10 has a malfunction . (See Note 2)
9
IROFAILURE
IRO has a malfunction.
It may be missing or too fast or too slow. ·
10
U27
ROM
FAILURE
U27's Internal checksums do not match. It may be a ROM failure, or Its
associated connections and connectlngdevices are causing it to ap-
pear to have a problem. (The following U26 test is skipped.)
1 1 U26 ROM FAILURE
U26's internal checksums do not match.
Notes:
1. This test assumes that the Coin Door Is OPEN; it is Initiated ONLY by pressing the CPU
Diagnostic Switch (SW2).
2. Altematively,
its associated connections or connecting devices are causing the IC to ap-
pear to have problems .
"Blngs''will not be heard if the game processor displays "Press Advance for
Report".
If the this test did not isolate the problem. turn the Volume Control for maximum
output. Momentarily touch a powered-up AC soldering iron on the center tap of the
Volume Control.
Be sure the Audio Board has +12V. -12V. +5Vand Ground.
CAUTION
DO Nar use a soldering iron over 40 watts. Note also that cordless soldering irons
will NOTwork for this test.
Hearing a low hum or a 'click' indicates that the power amplifier. the Volume
Control. and the speaker are operating satisfactortly, as is the sound circuit
cabling. Not hearing a sound requires repeating the test with the Volume Control
turned part way down. to determine whether the Volume Control is faulty. Also.
check the cable connectors for proper mating, and that no broken wires affect this
circuit.
1-41
Test/Diagnostic Procedures