Dell 1135N Service Manual page 127

2) LSU Error
Description : "PMOTOR ERROR/HSYNC ERROR'
1. Check whether the LSU
connector is disconnected or not.
2. Check whether the LSU
motor is rotating or not.
3. Check the HSYNC signal.
Service Manual
Alignment and Troubleshooting
Replace a LSU
Replace a main board if the same
error occurs again after replacing
a LSU.
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