# How to Fix Frigidaire Error E43 (Door Lock Triac)
The Frigidaire error code **E43** is a critical internal fault indicating an electrical problem associated with the machine’s primary control system. Unlike errors like E41 (which indicates the door is simply unlocked), E43 points to a failure on the Main Control Board itself.
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## 1. Explanation: What Frigidaire Error E43 Means
The E43 code specifically means there is a detected failure in the **Door Lock Triac**.
**What is a Triac?**
A Triac is an electronic component located on the main control board (often called the PCB or CCU—Central Control Unit). Its job is to act as an electrical gate, controlling the flow of AC power directly to the door lock mechanism.
If the Triac shorts, fails, or reports inconsistent voltage, the washer cannot safely determine the state of the door lock. It triggers the E43 error and immediately stops operation to prevent flooding or injury.
**The Likely Culprit:**
Because the Triac is permanently soldered onto the Main Control Board, this error is almost exclusively fixed by **replacing the Main Control Board.**
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## 2. Step-by-Step Diagnosis and Fix
Before resorting to purchasing a new control board, you should perform standard power checks and basic visual inspection to ensure a simple external factor isn’t causing the fault reading.
### Step 1: Power Reset the Washer
Sometimes a temporary electrical glitch can cause the control board to misread the Triac.
1. **Unplug the Washer:** Completely disconnect the machine from the power outlet. Do not simply turn it off.
2. **Wait 5 Minutes:** Allow all residual electrical charges to dissipate from the capacitors.
3. **Plug Back In:** Restore power and attempt to run a short cycle.
If the E43 immediately reappears, proceed to the physical check.
### Step 2: Check Connections and Water Damage
The E43 is an electrical fault, so you need to look for signs that water or corrosion might have shorted the control system.
** Safety Warning:** Unplug the washer before beginning any physical inspections.
1. **Inspect the Door Lock Wiring:** Carefully locate the wiring harness connecting the door lock mechanism to the main chassis wiring. Look for obvious signs of frayed wires, burn marks, or corrosion near the lock.
2. **Inspect the Control Board (If Accessible):** On most Frigidaire models, the main control board is located near the top or behind the main control panel. If you can safely access the board, look for any signs of water damage, burnt components (often indicated by a foul smell or black/brown residue), or damaged connectors.
If you find physical water damage on the connectors or the board itself, this confirms the board must be replaced.
### Step 3: Conclude the Diagnosis
The E43 error is a definitive internal control board failure.
* If the power reset (Step 1) failed, and
* If your visual inspection (Step 2) confirms the external wiring is intact and the door lock mechanism seems mechanically sound,
… then the failure lies within the electronic components of the Main Control Board, and the board requires replacement.
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## 3. The Solution: Replacing the Main Control Board
Replacing the Main Control Board is the only way to resolve a Door Lock Triac error (E43).
**1. Safety First:** Unplug the washer and shut off the water supply.
**2. Access the Board:** Depending on your model (front-load vs. top-load), you will likely need to remove the top panel or the back access panel to locate the Main Control Board.
**3. Document Connections:** Before removing the board, take pictures of all wiring harnesses and connections. This ensures you reinstall the new board exactly the same way.
**4. Replace the Board:** Disconnect all harnesses, remove the mounting screws/clips holding the old board, install the new board, and reconnect all wiring.
**5. Test:** Restore power and run a short diagnostic cycle to clear the error.
**Crucial Note on Ordering:** Main Control Boards are model-specific. You must use the full model number of your Frigidaire washer (usually found on a sticker inside the door frame or on the back) to ensure you order the correct replacement board.
Check the price for a replacement Main Control Board here: https://www.amazon.com/s?k=Frigidaire+Main Control Board&tag=trivian-20