Seeing an E9 error code pop up on your Thermador range display? Don’t worry; this error is usually easy to diagnose and repair. The E9 code indicates that the electronic control board is not detecting proper airflow from the internal cooling fans during heating cycles.
By methodically inspecting the fan wiring, testing the motors, and replacing any defective parts, you can often resolve the issue yourself.
This article will explain what causes E9 errors, provide step-by-step troubleshooting tips, and teach you how oven cooling systems work so you can tackle the repair confidently. With the right knowledge, you can get your oven back up and running again.
How Oven Cooling Fans Work
Oven cooling fans play an important role in keeping your oven operating safely. This section will explain what oven-cooling fans do and why they are necessary.
What Are Oven Cooling Fans?
Modern ovens have electronic controls instead of old-fashioned knobs. These electronic controls can get too hot and stop working if they overheat.
To prevent overheating, one or more small cooling fans are installed behind or below the oven cavity. The fans switch on anytime the bake, broil, or self-clean modes are being used.
What Do Cooling Fans Do?
The main jobs of the cooling fans are:
- Keep the temperature-sensitive electronic controls and wiring from overheating
- Quickly blow out heat when you open the hot oven door
- Provide airflow needed for convection cooking
- Stop plastic parts like switches and wire coating from melting
Why Are Cooling Fans Important?
If the cooling fans stop working, the oven’s electronic parts can be damaged by high heat. This can cause oven failures, errors, and disable the oven as a safety measure.
The E9 error code means the electronic control board is not detecting proper airflow when the oven is hot. This is usually caused by a cooling fan issue.
What Causes E9 Cooling Fan Error Codes?
Seeing an E9 error code pop up on your oven display can be frustrating. But don’t worry – this error is usually easy to diagnose and repair if you understand what’s causing it.
The E9 code means that the electronic oven control board is not detecting the proper airflow from the internal cooling fans during a heating cycle. This triggers the error as a safety precaution.
There are a few common reasons why the oven control stops sensing the cooling fan operation when the bake, broil, or self-cleaning mode is turned on:
1. Loose, Damaged, or Disconnected Fan Wiring
- Over time, the wiring that connects the cooling fan motors to the oven’s control board can come loose or get damaged from normal wear and tear.
- This can create intermittent contacts or open circuits that prevent power from reaching the fans properly.
- Disconnected fan wires are an obvious and easy issue to spot when inspecting the wiring harness.
2. Cooling Fan Blades Are Obstructed
- If debris, crumbs, or spills accumulate inside the oven over time, this can physically block the cooling fans from spinning normally.
- Obstructed fan blades that cannot rotate freely will not circulate air as needed.
- Visually inspect the fan assemblies for any blockages and clean them as needed.
3. Seized Bearings, Jammed Blades or Burnt-Out Fan Motors
- The motors that power the cooling fans can fail over time due to normal wear and tear.
- Excessive heat exposure, lack of lubrication, and age can lead to seized bearings, stuck blades that won’t spin, or motors that burn out and stop running completely.
- Physical inspection and voltage testing at the fan wiring connectors can identify failed fan motor issues.
4. Defective Oven Control Board
- The electronic control board regulates power to the oven components like heating elements, displays, and fans.
- If the control board is malfunctioning, it may not properly supply voltage to the cooling fan motors even though the oven is in heating mode.
- Checking the voltage at the fan motors while the oven is on helps determine if the issue is with the control board or the fans themselves.
The bottom line is that the E9 error points to the oven’s control board not sensing the required internal airflow during heating operation. Methodically inspecting the fan wiring, testing the fan motors, and ultimately replacing defective parts is key to resolving the problem.
Step-By-Step Cooling Fan Wiring Inspection
If you see an E9 error on your oven display, one of the first things to check is the cooling fan wiring. Loose or damaged wires are a common cause of the fans not getting power during heating modes.
Follow these steps to thoroughly inspect the fan wiring in your oven:
Disconnect Power to the Oven
- Start by turning off the power to the oven at the breaker panel or unplugging the unit.
- Verify the oven is completely powered down before continuing. This ensures your safety while working on the electrical system.
Remove the Rear Access Panel
- The wiring that connects the oven’s control board to the cooling fans is usually located on the rear of the appliance.
- Remove the access panel or loosen any mounting screws to expose the fan wiring harness.
Locate and Identify the Fan Wires
- Visually inspect the wiring and identify the specific wires that supply power from the control board to each of the fan motors.
- There may be multiple wire pairs, one for each fan.
Check Wire Connections
- Make sure the fan motor wires are inserted completely into both the control board terminals and the fan motor plugs.
- Remove and reseat any loose connections you find by unplugging and firmly replugging the connectors.
Inspect for Damaged Wires
- Closely check the entire length of each wire for any sections damaged, burnt, or with deteriorated insulation.
- This can cause intermittent power issues.
Check for Electrical Continuity
- Use a multimeter to test each wire for continuity. This will check for any open circuits that prevent power transfer.
Repair or Replace Any Compromised Wires
- If you identified any damaged or disconnected wires, make repairs before proceeding. This avoids misleading diagnoses.
- Thoroughly inspecting and ensuring solid fan motor wiring connections is the first step in diagnosing an E9 oven error. This can often reveal the issue.
Diagnosing Cooling Fan Operation Issues
There are a few simple steps we can take to figure out if the cooling fans are working properly in your oven. Let’s break this down step-by-step:
Visually Check for Obstructions
First, we’ll do a visual check. Open the rear access panel on your oven so you can see the fans clearly. Are the fan blades free to spin, or is something blocking them? Debris or dust can get inside over time and stop the fans from spinning. Go ahead and remove any junk you see, being careful when moving parts.
Voltage Test During a Bake Cycle
Now it’s time for a quick test using a handy tool called a multimeter. This lets us check if power is getting to the fan motors when it should. Plug in your oven and start a bake or broil cycle to turn on the heating elements.
While it’s heating up, place the multimeter probes on the wiring connector inside the fan motor. This will show us the voltage, or “power,” coming through during a cycle. Is it showing around 120 volts? If so, the wiring to the fan looks good.
Does the Fan Spin With Power?
So we’re getting voltage, but is the fan actually moving? If it’s not spinning but getting power, then the motor inside may be broken. The shaft could be stuck. But if the voltage is there and it still doesn’t spin, then it’s time for a new fan motor part. Those little motors work hard and can wear out over time!
No Voltage Means More Troubleshooting
On the other hand, if your multimeter showed zero volts during the bake cycle, then the problem could be somewhere in the wiring or the main control board. That’s not as simple a fix and will take more diagnosis. We may need to check wiring connections or consider replacing the entire control board if it can’t power the fans properly.
Putting It All Together
By doing some basic checks like looking for debris, testing for power, and seeing if fans spin, we’ve eliminated a few possible causes. And we’ve identified if it’s a simple fan motor fix or something more involved. The multimeter is a handy tool for narrowing things down without too much guesswork. Now you know the right next steps to really diagnose your cooling fan problem.
Replacing a Broken Fan Motor
Alright, so based on our testing it looks like a new cooling fan motor part is needed. Let’s go through the simple steps to swap it out:
Look Up the Right Replacement Part
Finding the exact correct part is important. The good news is oven manufacturers make this easy. Just have your model number handy and click the link provided to search a compatibility tool. This will pull up fan motors fitting your specific oven. No guesswork!
Remove the Old Motor
With the right part in hand, it’s time for some light mechanical work. First, remove any mounting screws or clips securing the old motor in place. Does it just pop out once unfastened? Get a good look at how it’s situated. Then unplug the wiring connector – be careful not to break any small prongs inside.
Install the New Motor
mounting the new fan motor is just the reverse of removing the old one. Start by plugging in the wiring connection, making sure it’s fully seated. Then use the screws or clips to firmly fasten the motor at the same angle as the previous one. Wondering if it’s in there correctly? Give it a gentle tug test before moving on.
Check Your Work
Does anything look potentially problematic? Take one last look to verify proper installation and that no wiring could get pinched or bind anything once you close it up. Don’t be afraid to double-check – it will save headaches down the road. With any luck, you should now have a fully operational cooling fan once again!
Power It Back Up
All that’s left is to restore power to your oven. Then, the bake function is fired up to test that the new motor is spinning smoothly. If all goes well, your E9 error should disappear, and cooking can continue normally.
Replacing the Oven Control Board for E9 Error Codes
The oven control board is the brain that operates the various components in your oven. It controls everything from the heating elements, lock lights, fans, and displays. If this control board sustains damage or fails, it can cause all kinds of unpredictable operation problems.
One common symptom of a faulty oven control board is getting an E9 error code. This indicates the board is not properly sensing that the internal cooling fans are running when the oven is in a heating cycle. While the root cause could be bad fans, wiring, or obstructed blades, a defective control board is very often to blame.
If you have isolated the issue down to control board failure through troubleshooting, here is what to do:
Step 1: Identify the Correct Replacement Control Board
- Look up the exact part number for the replacement control board that matches your oven model.
- Oven manufacturers frequently update their boards, so the part number is critical.
- Using a board for a different model, even if it looks the same, will not work properly.
Step 2: Disconnect Power and Remove the Old Board
- Shut off the power to the oven at the breaker panel or unplug it. Verify it is fully powered down.
- Label each wire connection so you can match them up to the replacement board terminals.
- Remove any mounting screws or brackets to fully extract the existing control board.
Step 3: Install the New Oven Control Board
- Carefully position the replacement board and attach any mounting brackets or hardware.
- Does everything line up with the oven wiring? Double-check that all wire terminals match properly.
- Firmly insert each wire into the corresponding connection on the new control board.
Step 4: Restore Power and Retest Oven
- Turn the power back on or plug the oven back in.
- Initiate a bake cycle and use a multimeter to verify that voltage is now present at the fan motors.
- If the fans run properly and the E9 error code does not return, you fixed it!
Step 5: Recheck Your Work
- With any appliance repair, it is critical to re-check your work afterward.
- Did any wires get loose? Are all brackets and screws tight? Do a final inspection.
Replacing the oven control board is often the solution if you have isolated the E9 problem to control board failure. Take precautions to install the correct replacement part for your model.
Also Read: How to troubleshoot & resolve an E12 error on a Thermador wall oven
Additional Tips
Repairing appliances often takes some trial and error. Even after you think you’ve fixed an E9 oven error code, it may come back later. Here are some handy troubleshooting tips:
Double Check All Wiring Connections
Loose wiring is a common reason the E9 code returns after repair. Go back and inspect these key areas:
- Are the fan motor wire plugs firmly inserted at both ends?
- Do all pins look straight and undamaged in the wiring connectors?
- Are the wires securely attached to the oven control board terminals?
- Give each wire a gentle tug test to see if any are loose. Refasten any loose connections.
Wiring can work itself loose over time after the vibration of daily oven use. It pays to double-check!
Monitor Oven Temperatures
An independent oven thermometer should be placed inside the oven cavity while testing. This lets you identify any hot spots:
- Place thermometers near the heating elements and the top of the oven.
- Operate a bake cycle and watch for temperatures exceeding safety limits.
- Hot spots point to a lack of proper airflow from failing fans.
Check for Debris and Obstructions
The buildup of food, grease, packaging materials, or other debris can block cooling fans:
- Carefully inspect the oven cavity sides, rear, bottom, and the area around the heating elements.
- Remove any buildup with an oven cleaner and nylon scrub pad.
- Make sure no obstructions prevent fan blades from spinning freely.
Conclusion
Dealing with error codes can be frustrating, but understanding what causes them is power. Let’s review the core takeaways:
- E9 indicates the oven control board doesn’t sense proper airflow from the internal cooling fans during a heating cycle. This protects the oven from overheating damage.
- Start by checking fan wiring for any loose connections, damage, or corrosion. Faulty wiring is an easy fix.
- The fans themselves could be jammed and unable to turn. Remove any obstructions. Test fan motors for operation and replace them if needed.
- If the fans test ok, the oven control board is likely at fault, preventing voltage from reaching the fan motors. Swap in a replacement matched to your model.
- Always double-check your repair work afterward. Wiring can vibrate loose, debris can re-accumulate, and temps may still overheat.
- Be methodical and patient in your diagnosis. Appliance issues often require swapping multiple parts to isolate the true problem.
The goal is to educate yourself on what internally causes common error codes like E9. This empowers you to tackle the repair confidently. With the right knowledge and testing, you can absolutely get your oven back up and running again.