{"id":6381,"date":"2025-08-17T13:31:37","date_gmt":"2025-08-17T11:31:37","guid":{"rendered":"https:\/\/wp.stromer-tech.info\/?post_type=ht_kb&p=6381"},"modified":"2026-07-08T03:00:52","modified_gmt":"2026-07-08T01:00:52","slug":"measure-mosfets","status":"publish","type":"ht_kb","link":"https:\/\/wp.stromer-tech.info\/en\/knowledge-base\/mosfets-messen\/","title":{"rendered":"Controller (MCU) \u2013 Test MOSFETs"},"content":{"rendered":"

The power electronics for the motor's support control were housed within the motor in the first models (ST1 \/ V1 \/ V1.1). Due to various issues (temperature, water, humidity, and subsequent corrosion), they were first potted and eventually consolidated into a separate unit, the controller or MCU (Motor Control Unit), placed under the down tube or in the battery compartment (e.g., ST2-Belt, ST7).<\/p>\n\n\n\n

Defects are quite common. As the assembly has been encapsulated in epoxy resin since around 2018, it is virtually impossible to repair.<\/p>\n\n\n

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Fully encapsulated ASI controller<\/figcaption><\/figure>\n<\/div>\n\n\n

Defects are often, but not always, visible. If MOSFETs \"explode\", measurement is pointless, the damage is visually obvious.<\/p>\n\n\n

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\u201eExploded\u201c MOSFET tore a hole in the circuit board<\/figcaption><\/figure>\n<\/div>\n\n\n

Even a defect in the charging section does not require further forensics.<\/p>\n\n\n

\n
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Defective Charching Secion on the controller board<\/figcaption><\/figure>\n<\/div>\n\n\n

Error E 210012 & E 210109<\/h3>\n\n\n\n

If the Omni shows error E 210012 & 210109, Stromer has instructions on what to visually check before installing a new battery. However, this is only possible with controllers that have a transparent seal.<\/p>\n\n\n

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\"\"<\/figure>\n<\/div>\n\n\n

Error E 21000E \u2013 during driving<\/h3>\n\n\n\n

If error E 21000 appears, it could indicate a problem with the CAN bus. To check this, go to the service menu and verify if the CAN bus is locked. Instructions on how to do this can be found in the chapter ERROR AND WARNING MESSAGES. ,E 21000E \u2013 while driving\u2018<\/a><\/em><\/p>\n\n\n\n

No optical errors \u2013 check MOSFETs<\/h3>\n\n\n\n

If no optical problems are apparent, it becomes difficult to diagnose the error. A simple electrical test of the MOSFETs is possible, but only with controllers that are not potted. I am linking the document here. Testing for blown MOSFETs<\/a> the company GRIN Technologies (ebikes.ca), which very easily illustrates the procedure with a multimeter.<\/p>\n\n\n\n

<\/p>","protected":false},"excerpt":{"rendered":"

Die Leistungselektronik f\u00fcr die Unterst\u00fctzungsregelung des Motors war bei den ersten Modellen (ST1 \/ V1 \/ V1.1) im Motor untergebracht. Aufgrund diverser Probleme (Temperatur, Wasser, Feuchtigkeit und damit Korrosion) wurde sie zuerst vergossen und schliesslich in eine separate Baugruppe, den Controller bzw. MCU (Motor Control Unit), unter das Unterrohr oder…<\/p>","protected":false},"author":1,"comment_status":"open","ping_status":"closed","template":"","format":"standard","meta":{"footnotes":""},"ht-kb-category":[163],"ht-kb-tag":[191,536,417,418,416,414,415,413],"class_list":["post-6381","ht_kb","type-ht_kb","status-publish","format-standard","hentry","ht_kb_category-messen","ht_kb_tag-asi","ht_kb_tag-e21000e","ht_kb_tag-e210102","ht_kb_tag-e210109","ht_kb_tag-eds-mc3","ht_kb_tag-leistungselektronik","ht_kb_tag-mcu","ht_kb_tag-mosfet"],"_links":{"self":[{"href":"https:\/\/wp.stromer-tech.info\/en\/wp-json\/wp\/v2\/ht-kb\/6381","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wp.stromer-tech.info\/en\/wp-json\/wp\/v2\/ht-kb"}],"about":[{"href":"https:\/\/wp.stromer-tech.info\/en\/wp-json\/wp\/v2\/types\/ht_kb"}],"author":[{"embeddable":true,"href":"https:\/\/wp.stromer-tech.info\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wp.stromer-tech.info\/en\/wp-json\/wp\/v2\/comments?post=6381"}],"version-history":[{"count":19,"href":"https:\/\/wp.stromer-tech.info\/en\/wp-json\/wp\/v2\/ht-kb\/6381\/revisions"}],"predecessor-version":[{"id":12220,"href":"https:\/\/wp.stromer-tech.info\/en\/wp-json\/wp\/v2\/ht-kb\/6381\/revisions\/12220"}],"wp:attachment":[{"href":"https:\/\/wp.stromer-tech.info\/en\/wp-json\/wp\/v2\/media?parent=6381"}],"wp:term":[{"taxonomy":"ht_kb_category","embeddable":true,"href":"https:\/\/wp.stromer-tech.info\/en\/wp-json\/wp\/v2\/ht-kb-category?post=6381"},{"taxonomy":"ht_kb_tag","embeddable":true,"href":"https:\/\/wp.stromer-tech.info\/en\/wp-json\/wp\/v2\/ht-kb-tag?post=6381"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}