Display, keypad, or selection problem

S.E.M. Inc. CTX MDB Tester PRO

Machine type unverifiedLow confidenceExact parts not verified

Use this when the display, keypad, selections, or user controls are the main clue.

Low VoltageOperator8-12 min

Display / keypad8 stepsoperator-intermediate

Checklist

Guided Diagnostic Steps

Work from low-risk checks toward technician-level inspection only when evidence supports it.

Printable checklist

You can read or print the route now. The first checkbox click opens the service contact gate.

lead gated

1
Diagnostic step 1
operator-intermediatemedium
Verify 'V' harness pin continuity between the tester port and the MDB male/female connectors.
Evidence to note: meter-reading
2
Diagnostic step 2
operator-intermediatemedium
Check for 24V-34V DC on the MDB bus. If unavailable, attempt power via SEM adapter A06205.
Evidence to note: note
3
Diagnostic step 3
operator-intermediatemedium
Observe Green LED. Confirm a slow rhythmic flash indicating standby power is reaching the logic board.
Evidence to note: note
4
Diagnostic step 4
operator-intermediatemedium
Depress 'ON' button for a minimum of 1 full second. Monitor LCD for Version 1.6 splash screen.
Evidence to note: note
5
Diagnostic step 5
operator-intermediatemedium
Navigate to 'System Parameters' -> 'Prices Programming'. Increment Selection 1 to $9.95.
Evidence to note: note
6
Diagnostic step 6
operator-intermediatemedium
Confirm that pressing the 'UP' arrow again causes the price to wrap around to $0.00.
Evidence to note: note
7
Diagnostic step 7
operator-intermediatemedium
Perform a simulated vend. Navigate to 'Audit' and verify the transaction was logged.
Evidence to note: note
8
Diagnostic step 8
operator-intermediatemedium
Connect serial printer to the rear port and execute 'Print Audit'. Verify printout legibility.
Evidence to note: note

No special tools listed

Exact public parts list not verified yet. Use this route to identify the system before ordering.

Candidate areas for part verification

Display and keypad partsCabling & External SupportCore ElectronicsPower componentsVend path components

Switch routes if this symptom is not the closest match.