Legacy Thermador Pro-Harmony Range E1 (Blue-Light Code 22): EEPROM Error

What E1 means

If an older Professional Series range (PDR30/36/48 or PRG30/36/48, the legacy Pro-Harmony gas and dual-fuel line) blinks the blue oven light twice and then the blue heating light twice, the control is reporting E1, an EEPROM error. That points to the control's stored memory, and the pattern repeats for as long as the condition lasts. Newer Thermador units use the same symbol differently.

Usual causes of E1

Control board memory (EEPROM) not reading correctly

✓ A safe check worth trying

1. Count the blue light flashes and write the pattern down. 2. Shut the oven off and wait a couple of minutes. 3. Restore power at the breaker, then try the oven once more. 4. If the two-then-two pattern comes back, stop using the oven and call us, because the control itself needs a technician.

! Why you should stop here

The memory lives on the control board, which owners cannot test safely.
Swapping boards by guesswork on a legacy range gets expensive quickly.
Confirming the diagnosis first lets us quote the work in writing before any part is ordered.

Taking off a panel yourself does not by default void a manufacturer warranty, yet it can lead to accidental damage, and some manufacturers attach their own service terms. Read your warranty paperwork, or ask us, before you decide.

→Same appliance

More Range codes

E3E3 on an Older Thermador Pro-Harmony Range (Light Code 10): Open Oven Sensor F7Legacy Thermador ESC30/GSC30 Range F7: Stuck or Shorted Function Key E4Thermador Pro-Harmony Range Showing E4 and Light Code 12: Shorted Oven Sensor F8Older Thermador 30-Inch Range Cancels Cooking with F8 (Supervisory Error) E5Legacy Pro-Harmony Thermador Range E5 Means Potentiometer Failure (Light Code 21) F9Legacy Thermador ESC30/GSC30 Range with F9: Door Latch Supervisory Error E6Thermador PDR/PRG Range E6, Blue Lights 3-then-2: Over Temperature While Cooking F1Legacy RDF/REF 30-Inch Range F1: Stuck Buttons or Latch Switch

E1E1 questions

Does a power reset fix E1 on an older Pro-Harmony range?

It can clear a one-time glitch, so one reset is worth trying. If the two-then-two flash pattern returns, the control is still reporting a memory problem and a technician should examine it.

Can I still bake while the blue lights flash?

The service document does not call this error harmless, so we advise against relying on the oven. Turn it off at the control and have us look before you cook with it again.

How do I know my range is the legacy kind?

Look for a PDR or PRG prefix with a 30, 36 or 48 size on the rating plate. Send us the full number and we confirm the details on site.