EN

Severity: Moderate ✱

Speed Queen Dryer Error Er CO – Causes & Fix

The Speed Queen dryer's display control lost contact with the board that drives the motor and heat.

Unverified: this manufacturer-specific definition comes from a single source or varies by model. Confirm it with a brand-specific scan tool.

At a glance

Severity: 3/5 – Moderate3/5

Severity: Moderate

Meaning
Control Communication Error – Boards Not Talking
Typical repair cost
$0–$550
DIY difficulty
Hard

On Speed Queen dryers with an electronic display, Er CO (also written E CO or E:CO) is reported by technicians as a communication error: the user control and the output board that switches the motor and heat aren't exchanging data correctly. Speed Queen's consumer manuals we checked don't define the code, so treat this meaning as unverified and model-dependent – some reports tie it to a sensor signal instead. Communication faults are often triggered by a power glitch, then by a loose or oxidized harness connector between the boards, and only after that by a failed board. Mechanical-dial Speed Queen dryers without a display don't show this code at all.

How it looks on the display

Speed Queen Dryer display showing error Er CO

Model families & display variants

Model familyShowsNote
Speed Queen dryers with electronic displayEr COSome displays alternate Er and CO, others show them together.
Other display stylesE CO / E:COSame code written with a different separator.
Speed Queen dryers with mechanical dialsnoneNo display, so faults show as a dryer that won't start rather than a code.

Safety first · Consult a professional

Turn off the dryer's breaker before removing the console or any panel – the output board switches 240 V on electric models. On gas models, don't disturb the gas connection or burner area; leave internal work to a qualified technician.

  • Unplug the appliance or switch off the breaker before opening any panel. Mains voltage can kill.

Symptoms

  • Er CO, E CO or E:CO on the display, often right at power-up
  • Keypad responds but the drum never starts
  • The dryer stops mid-cycle and shows the code
  • The code appeared after a storm, outage or breaker trip
  • Intermittent: some days it works, other days it won't start

Possible causes

Ranked by how often each cause is behind this code (editorial estimate).

  1. Power glitch leaving the controls out of sync 30%
  2. Loose or oxidized connector on the harness between the boards 26%
  3. Damaged communication wiring (pinched, chafed or rodent damage) 16%
  4. Output (machine control) board failure 14%
  5. User interface / display control failure 10%
  6. Supply voltage problem at the outlet 4%

Fix it step by step

Diagnostic flow: Er CO1Full power reset2Check the supply3Record when it happens4Check your warranty5Reseat the harness (experienced DIY,out of warranty)

  1. Full power reset

    Switch off the dryer's breaker or unplug it for at least 5 minutes so both boards lose power completely, then restore power and start a short timed cycle.

  2. Check the supply

    Confirm the breaker isn't half-tripped and the plug sits firmly in the outlet. A dryer sharing a flaky connection can drop one board's supply for a moment and trigger a communication error.

    Tools: Flashlight

  3. Record when it happens

    Note whether the code shows at power-up, at start, or partway through drying. A fault that appears only once the dryer is warm often points to a connector or board that fails with heat.

  4. Check your warranty

    Many Speed Queen dryers carry a long parts-and-labor warranty. Check yours with the serial number before opening panels or buying boards, since unauthorized repairs can complicate a claim.

  5. Reseat the harness (experienced DIY, out of warranty)

    With power off, open the console and check the connectors on the communication harness between the control and the output board. Unplug and reseat each one, looking for green corrosion or bent pins.

    Tools: Screwdriver, Flashlight

How to reset Er CO

  1. Turn off the breaker or unplug the dryer for at least 5 minutes.
  2. Restore power and wait a few seconds for the display to settle.
  3. Start a short timed cycle.
  4. If Er CO returns, stop resetting and schedule service.

Where the parts are

Dryer: lint filter and exhaust vent path – Er CO1234567
Dryer: lint filter and exhaust vent path
  1. 1Lint filter
  2. 2Exhaust vent
  3. 3Heating element
  4. 4Condenser
  5. 5Motor
  6. 6Temperature sensor
  7. 7Door switch

Repair options & costs

RepairDIY?Estimated cost
Power reset / breaker check Yes $0
Reseat or clean harness connectors Yes $0–$20
Harness repair by a technician No $150–$300
Output board replacement No $250–$500
User interface / control replacement No $250–$550

Rough US estimates; technician call-out fees vary by region. Not a quote.

When to call a technician

Contact a Speed Queen authorized technician if Er CO comes back after a 5-minute power reset, especially while the dryer is under warranty. A technician can check which board stops communicating instead of guessing between two expensive parts.

Frequently asked questions

What does Er CO mean on a Speed Queen dryer?

Technicians generally describe it as a communication error between the display control and the board that drives the motor and heat. Speed Queen's consumer manuals don't define it, so confirm with an authorized technician.

Is the dryer Er CO the same as the washer Er CO?

Speed Queen uses similar code styles on washers and dryers, but the boards and wiring differ. Troubleshoot the dryer on its own terms and don't order washer parts.

Should I replace the control board myself?

Not as a first step. A loose connector or a power glitch causes many communication codes, and board swaps on a warranty-covered dryer are better left to an authorized technician.

Sources