Dell 2135cn Service Manual page 426

Step
Checking the connectors for connection
Check the connections between the PWBA MCU and LED
ASSY ERASE.
Are P/J141 and P/J14 connected correctly?
7
Checking the HARN ASSY LVPS for continuity
Disconnect J14 from the PWBA MCU.
8
Disconnect J141 from the LED ASSY ERASE.
Is each cable of J14 <=> J141 continuous?
Checking the power to LED ASSY ERASE
Disconnect the connector of J14 from the LED ASSY
9 ERASE.
Is the voltage across P14-15pin <=> ground on the PWBA
MCU, about +3.3 VDC?
Checking the PHD UNIT for connection
Remove the PHD UNIT.
Are five HV terminals on the PHD UNIT, and five springs on
the frame (PL4.1.10 and PL4.1.15 to 18) dirty and/or
deformed?
10
Checking after reseating the PHD UNIT
11 Reseat the PHD UNIT.
Is the image printed correctly?
Version 1 2008.02.01
Check
1 - 398
Chapter 1 Troubleshooting
Remedy
Yes
Reconnect the
connector(s) P/
Go to step 8. J141 and/or P/J14
surely, then go to
step 8.
Replace the
Go to step 9. HARN ASSY
LVPS.
Replace the LED Replace the
ASSY ERASE. PWBA MCU.
(Refer to Removal (Refer to Removal
12/ Replacement 31/ Replacement
48.) 29.)
Clean and/or
replace the PHD
Go to step 11.
UNIT or
SPRING(s).
End of work. Go to step 12.
No