PC ER Communication error between main board and display
Samsung PC ER (also displayed as 'PC Er' on some panels) means the main control board has lost communication with the front display panel. Start by unplugging for 5 minutes — this often resolves it. If it returns, reseat the ribbon cable connecting the two boards.
What Causes This Error
Loose wire connection between boards
highA ribbon cable or wire harness between the main board and display/UI board has come loose.
Power surge damage
mediumA voltage spike damaged communication circuits on one or more control boards.
Failed control board
mediumOne of the PCBs has a failed component and can no longer communicate.
Corroded connector pins
lowMoisture has caused connector pins to corrode, creating intermittent connections.
How to Fix Error PC ER
- 1
Power cycle the appliance
Unplug for 5 minutes. Communication errors are frequently caused by electrical glitches that clear with a hard reset.
- 2
Check for loose connections
Unplug the appliance, remove the access panel(s), and reseat every wire connector you can find between the control boards. Press each one firmly until it clicks.
Always unplug before accessing internal components. - 3
Inspect ribbon cables
If your appliance uses flat ribbon cables between boards, check for tears, kinks, or connectors that have worked loose from vibration.
- 4
Look for signs of damage
Examine both control boards for burned components, bulging capacitors, scorch marks, or corroded connector pins. Any visible damage means that board needs replacement.
- 5
Replace the communication harness
If connectors look corroded or a cable is damaged, replace the wire harness between boards.
- 6
Replace the faulty board
If reseating connections doesn't help, one of the control boards has failed. The main control board is the most common failure.
Replacement Parts
If the steps above don't fix it, you may need one of these parts:
Main Control Board
$80-$250Display Board (Panel PCB)
$50-$150Wire Harness (Board to Display)
$15-$40When to Call a Professional
If you cannot identify which board has failed, or if the error appeared after a power surge or lightning strike
- Diagnosing which of multiple boards has failed requires specialized tools
- Power surge damage may affect multiple components
- Control board replacement often requires programming or calibration