Bosch Dryer E13 Error Code DIY Troubleshooting Guide

Seeing an E13 error code appear on your Bosch dryer can be confusing and concerning. But don’t worry – this post will guide you through what causes an E13 error, and provide fix-it tips to get your dryer heating and tumbling properly again.

What Triggers the E13 Error Code?

The E13 error code indicates that the maximum drying time has been exceeded on your Bosch dryer model. It is essentially a timeout error.

There are a few common reasons why you may see an E13 error:

• The heating element has failed or is not working correctly. This could be the electric heating coil on electric models, or the igniter and gas valve on gas models.
• The load is too large or heavy for the drying cycle. Overloading the drum prevents clothes from drying effectively.
• Lint buildup or restriction in the ductwork is causing the dryer to run much longer than normal to dry a load.
• The external venting has a blockage or is disconnected.
• Thermistors or sensors are faulty, providing inaccurate readings.
• The control board has defective relay circuits.

When any of these conditions occur, the drying time exceeds the maximum limit programmed into the control board. Typically the max run time is between 90 to 130 minutes, depending on settings. Once the drying cycle goes over the limit, the E13 error shuts down the dryer for safety.

Tools Needed for Fixing an E13 Error

Repairing an E13 overdry error will require some or all of the following tools:

• Phillips and Torx screwdrivers – For accessing panels and removing components
• Nut driver set or wrenches – For detaching ducting, blower housing, and thermistors
• Needle nose pliers – For grabbing wires and manipulating connectors
• Multimeter – To test continuity, voltage, and resistance of components
• Exhaust duct inspection tools – Flashlight, duct brushes, vent testing manometer
• Soft-bristle brush – For cleaning sensors and thermistor probes
• Shop vacuum – For removing lint from internal ducts and housing

Additionally, a copy of the technical repair manual is recommended for schematics and disassembly instructions.

Read More: Don’t Get Burned! 14 Quick and Easy Oven Safety Tips

Step-by-Step Troubleshooting for the E13 error code

Follow these expanded troubleshooting tips when diagnosing an E13 error code on your Bosch dryer:

1. Thoroughly Test the Heating Element

Carefully inspect the heating element for any visible damage, charring, or broken coils. Electric heating elements can have coils break or burn out sections, while gas burner components can sustain physical damage.

Use a multimeter to check continuity through the heating element circuit.

• First, disconnect the power to the dryer.
• Then, detach the wire leads from the heating element terminals.
•  Set the multimeter to the ohms setting and touch the probes to the element terminals.

A good element will show a low and steady ohm reading, usually between 10 to 20 ohms.

If the reading is “OL” or infinite, that means the circuit is broken and the element is bad. Check for continuity on each terminal. Repeatedly move the probe connection points around to test the entire element. One break anywhere means the whole component needs replacement.

Reattach the wire leads and restore power. Now test for proper voltage to the element during operation. Voltage should match the dryer rating spec: 240V for electric or 120V for gas burners. No voltage points to a bad heating circuit relay on the control board.

2. Adjust Load Size and Content

Overloading the dryer drum creates dense, tightly packed loads. This prevents proper tumbling action and airflow which dramatically increases drying time. Consult your owner’s manual for rated capacity limits.

As a rule of thumb, the drum should be 50-75% full with space between items. Clothes should be able to lift and tumble freely when the dryer is running.

Separate large loads into smaller batches. Take extra heavy blankets and comforters to a laundry mat for oversized commercial dryers.

Try to wash lightweight synthetics and heavyweight kinds of cotton separately if possible. Loads will dry more evenly when fabrics are similar in weight and structure.

3. Clean Exhaust Ductwork Thoroughly

Carefully detach the flexible metal exhaust duct from the dryer outlet so the full length can be inspected. Support the ducting to avoid kinking. Use a bright flashlight to look for any tears, rips, or perforations that allow lint leakage. Ensure all duct sections and elbow connections are properly overlapped and sealed.

Use the rigid copper duct brush attachment for your vacuum cleaner to scrub out lint deposits inside the duct. Insert a vacuum hose with a brush from the dryer end through to the exterior vent hood outside. Apply several back-and-forth strokes to loosen the stuck-on lint and pull it out.

Remove the outdoor vent hood cover and use a small wire brush to dislodge any packed lint surrounding the duct termination point. Brush off the vent hood screen as well. Resecure any connections that are loose or sagging. The proper exhaust vent slope should be 1⁄4 inch per foot.

4. Clean and Check the Blower Wheel

The blower wheel is housed inside the large circular vent chamber on the back of the dryer. After disconnecting power, use a vacuum crevice tool to suck out any lint deposits surrounding the blower wheel inside the housing.

Carefully remove the blower wheel by detaching the retention nut in the center. Use caution not to bend or distort the wheel fins. Wipe it thoroughly with a lint-free cloth. Spin the wheel by hand to ensure it rotates freely with minimal friction or wobble.

Remove any lint caught on the motor mount or vent housing that may obstruct airflow. Reinstall the cleaned blower wheel and test run the dryer. Listen for abnormal noises or rubbing that could indicate damage.

5. Verify Thermistor Readings

The NTC thermistors use changes in resistance based on the surrounding air temperature in the dryer drum and venting. At room temperature, resistance should be around 10,000 ohms. A malfunctioning thermistor provides false temps to the control board.

Test thermistor accuracy by taking a resistance reading with a multimeter during a high heat cycle. Then cross reference it against the temperature versus resistance curve chart specific to your thermistor (available in repair manuals).

If resistance and temperatures don’t align with the chart, the thermistor is faulty and must be replaced. Pay close attention to readings during the early stages of a cycle when E13 errors are most likely to occur due to bad temps.

6. Verify Electrical Connections

Inspect every wire harness connection on sensors, heating circuits, switches, and the control board. Look for broken or loose plugs. Check for pins not fully seated in the connector. Wiggle wire harnesses while running to check for intermittent connections.

Make sure metal ground connections are tight and free of corrosion. Check that terminal block screws are torqued to proper specs. Review wiring diagrams to identify circuits and junction points related to operation.

Faulty connections that cut in and out during a cycle will cause erratic heating and sensor responses that lead to over-drying. Secure any loose plugs and defective harness wiring.

7. Replace Control Board

If you’ve verified all components have continuity and proper resistance, are visually intact, and wiring connections are sound, then the last remaining culprit may be a defective control board.

The relay circuits that energize the heating element may have shorted, or the programming timers may be malfunctioning. This causes abnormal cycle operation which leads to over-drying faults.

Before replacing the control, recheck that ventilation paths are clear, the exhaust system is functioning normally, and all plugs are firmly connected to their sockets. Swap in a known good control board to isolate the cause.

Read More: F46 Bosch Oven Error Code: A Troubleshooting Guide

Preventing Future E13 Errors

To help prevent E13 dry time errors in the future:

• Clean the lint filter before every load.
• Periodically remove lint from the exhaust duct and external vent hood.
• Follow loading guidelines and do not overfill the drum.
• Use automatic drying cycles rather than manually timed cycles.

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More Information

We hope this guide has helped you resolve your error code. If you have any questions regarding the repair, feel free to contact us at 1(877) 477-7278. Additionally, for further resources, make sure to check out our YouTube and Blog for DIY repair help and tips.