X-ray generators · CRX family

Philips CRX-125: troubleshooting and error codes

The ServiceForge knowledge base holds 21 documented symptoms for the Philips CRX-125, with 28 ranked causes, 34 diagnostic checks with test points and expected values, and 19 error codes. Each symptom below shows its causes and the first check; the rest is one connection away. Connect ServiceForge to your AI

Symptoms

XSC self-test specific code failures

Display shows specific failure codes (0-F) indicating fault in RAM, ROM, interrupts, serial, or timer circuits

Ranked causes

1. RAM address or data line fault (code 1) (rare)
2. Bad RAM cell (code 2 or 3) (rare)
3. CPUFAIL interrupt or reset circuit fault (code 6) (occasional)
4. Serial communication fault (code D) (occasional)
5. Reset circuitry fault (code F) (rare)

5 corrective actions and part numbers are in ServiceForge. Connect ServiceForge to your AI

XSC self-test failure during power up

Diagnostics fail one or more tests (0-F) during XSC power-up initialization; display shows hex failure code

Ranked causes

1. Another board (DIB/RCB) causing test failure (common)
2. Fuse FU2 on relay board is open (occasional)
3. Bad software or CPU or data/address lines (rare)

First check

Disconnect DIB/RCB bus cable

Test point: DIB/RCB connector on XSC
Expected: DIB/RCB bus cable disconnected

2 more checks with pass and fail actions, 3 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

CPUFAIL interrupt level seven test failed

CPUFAIL interrupt level seven test failed; may indicate DIP switch or RCB ACFAIL issue

Ranked causes

1. DIP switch 1 closed instead of open (common)
2. Constant ACFAIL signal from RCB (occasional)

First check

Verify DIP switch 1 position

Test point: XSC board DIP switch 1
Expected: Open

1 more check with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Application side boot failure

System would not boot to application side after diagnostics

Ranked causes

1. Bad reset circuitry Z38-5 (unknown)

First check

Verify reset circuitry Z38-5 operation

Test point: Reset circuitry Z38-5
Expected: Proper reset pulse during boot

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Bus address error test failed

Bus address error test failed during diagnostics

Ranked causes

1. Bus address line error or corruption (unknown)

First check

Run bus address error test

Test point: Bus address lines
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Calibration: Pre-heat calibrations radiation

Execute pre-heat calibration sequence before running seasoning on CRX-125 X-ray generator

Ranked causes

1. Pre-heat calibration required as prerequisite for seasoning (common)

First check

Access MANEXP master menu

Test point: Type 'manexp' (CR) at command prompt
Expected: MANEXP Master menu displays with 6 options

10 more checks with pass and fail actions, 1 corrective action, and part numbers are in ServiceForge. Connect ServiceForge to your AI

Calibration: Preheat learning after tube or XSC replacement

After X-ray tube or XSC replacement, preheat learning is required. Self-calibrating preheat system; incorrect settings may trigger error messages.

Ranked causes

1. New X-ray tube or XSC card installed (common)

First check

Monitor for preheat error messages

Test point: Error log or display
Expected: No 'Anode electrical overcurrent', 'Unable to cal preheats', 'Freq-max' or 'Freq-min' messages
Tools: iqout interface

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Calibration: X-ray tube centering radiation

X-ray tube position must be verified and adjusted to ensure the beam is centered. Film exposure at two detector positions reveals if tube is off-center; dark band should be centered in larger band.

Ranked causes

1. X-ray tube off-center position (unknown)

First check

Expose matrix film at tube detector position 300

Test point: manexp position 9600
Expected: Dark narrow band centered in larger band KV
Tools: manexp, matrix film or film without screen

1 more check with pass and fail actions, 2 corrective actions, and part numbers are in ServiceForge. Connect ServiceForge to your AI

DUART serial test failed

DUART serial communication test failed during diagnostics

Ranked causes

1. Bad DUART chip or serial connections (unknown)

First check

Run DUART serial test

Test point: DUART serial chip
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

HP display did not boot

Display failed to initialize or reach beginning of code at power-up

Ranked causes

1. Bad software, CPU, or data/address lines (unknown)

First check

Verify boot sequence initiation

Test point: CPU reset circuitry Z38-5
Expected: Normal reset pulse

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Interrupt level one test failed

Interrupt level one test failed during diagnostics

Ranked causes

1. Bad interrupt level one circuitry (unknown)

First check

Run interrupt level one test

Test point: Interrupt level one circuit
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Interrupt level six test failed

Interrupt level six test failed indicating fault circuitry issue on XSC

Ranked causes

1. Bad fault circuitry on XSC (unknown)

First check

Run interrupt level six test

Test point: XSC fault circuitry
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Interrupt level three test failed

Interrupt level three test failed during diagnostics

Ranked causes

1. Bad interrupt level three circuitry (unknown)

First check

Run interrupt level three test

Test point: Interrupt level three circuit
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Interrupt level two test failed

Interrupt level two test failed during diagnostics

Ranked causes

1. Bad interrupt level two circuitry (unknown)

First check

Run interrupt level two test

Test point: Interrupt level two circuit
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

NOV RAM test failed

Non-volatile RAM test failed during diagnostics

Ranked causes

1. Bad NOV RAM (unknown)

First check

Run NOV RAM test

Test point: NOV RAM module
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

RAM 5555hex test failed

RAM failed hex pattern 5555 test during diagnostics

Ranked causes

1. Bad bit in RAM (common)

First check

Run RAM 5555hex pattern test

Test point: RAM module
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

RAM AAAAhex test failed

RAM failed hex pattern AAAA test during diagnostics

Ranked causes

1. Bad RAM (common)

First check

Run RAM AAAAhex pattern test

Test point: RAM module
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

RAM address write test failed

RAM address or data lines failed during diagnostics

Ranked causes

1. Bad address or data lines (common)

First check

Run RAM address write test

Test point: RAM module connectors
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

ROM test failed

ROM checksum or integrity test failed during diagnostics

Ranked causes

1. Bad ROM or ROM data corruption (rare)

First check

Run ROM test

Test point: ROM module
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Timer Z48 test failed

Timer circuit Z48 failed during diagnostics

Ranked causes

1. Defective timer IC Z48 (unknown)

First check

Run timer Z48 test

Test point: Timer IC Z48
Expected: Test passes

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

XSC diagnostics failed

DS2 indicator on (yellow) should be off after diagnostics pass; Hex display shows diagnostic test in operation or last command executed

Ranked causes

1. F2 fuse open on Collector Relay PCB (common)

First check

Verify DS2 indicator state during power-up sequence

Test point: DS2 LED indicator
Expected: ON (Grn) after diagnostics complete

1 corrective action and part numbers are in ServiceForge. Connect ServiceForge to your AI

Error codes

Code	Meaning	Trigger	Severity
`0`	Didn't boot; CPU failed to start code execution	Power-up sequence does not reach beginning of firmware	critical
`1`	Failed RAM address write test	RAM memory unable to write test pattern to all addresses	critical
`2`	Failed RAM 5555hex test	RAM failed alternating bit pattern test	critical
`3`	Failed RAM AAAAhex test	RAM failed complementary bit pattern test	critical
`4`	Failed NOV RAM test	Non-volatile RAM memory test failed	error
`5`	Failed ROM test	Read-only memory checksum or read error detected	critical
`6`	Failed CPUFAIL interrupt level 7 test	CPU interrupt priority level 7 not responding or always asserted	error
`7`	Failed interrupt level 6 test	CPU level 6 interrupt not generated or stuck	error
`8`	Failed timer Z48 test	Timer component Z48 not responding or counting incorrectly	error
`A`	Failed interrupt level 3 test	CPU level 3 interrupt not generated	error
`Anode electrical overcurrent`	Anode current exceeds acceptable level	Incorrect preheat calibration after tube or XSC replacement	error
`B`	Failed interrupt level 2 test	CPU level 2 interrupt not responding	error
`C`	Failed interrupt level 1 test	CPU level 1 interrupt not generated	error
`D`	Failed DUART serial test	Serial communications controller (DUART) not responding	error
`E`	Failed bus address error test	Bus address error interrupt not generated during memory access test	error
`F`	Wouldn't boot to application side; reset circuit fault	CPU reset or boot sequence fails to reach application firmware	critical
`Freq-max`	Frequency at maximum limit	Preheat calibration issue or inverter selection error	warning
`Freq-min`	Frequency at minimum limit	Preheat calibration issue or inverter selection error	warning
`Unable to cal preheats`	Preheat learning/calibration failed	New tube or XSC installed without proper preheat setup	error

Likely causes and actions for each code are in ServiceForge. Connect ServiceForge to your AI

Community

0 fixes logged by technicians through their AI, with outcomes, for this model.

ServiceForge knowledge base record. Field-unverified unless technicians confirmed it. A teaching summary of the record, not a service manual. Export 2026-10-14.