2010 C300 Limp mode
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
Are there any other symptoms? Was it sudden and unexpected? What were you doing when it happened? How many miles on the car? Is the check engine light (CEL) on? Are there any messages on the instrument cluster?
Many systems can trigger limp mode: ESC, ABS, braking system in general, transmission, various engine parameters.
The first place to begin diagnosis is to check the car for trouble codes (DTCs) with a Mercedes specific scanner.
Many systems can trigger limp mode: ESC, ABS, braking system in general, transmission, various engine parameters.
The first place to begin diagnosis is to check the car for trouble codes (DTCs) with a Mercedes specific scanner.
MBWorld Fanatic!
Joined: Sep 2013
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2021 GLB250 FWD, 2023 GLA250 FWD, 2013 C250, 2015 GLK350, 2005 ML350SE, 2003 E320
P0721 points to the output speed sensor on the conductor plate inside the transmission. The sensor can be removed and replaced, but I think it is most common to get a rebuilt conductor plate. Before going inside the transmission, check the wiring to the transmission, that the plug has not been dislodged, and that there is no oil inside the connector.
Oil and filter service for the 722.9 7-GTronic transmission is at every 60k miles. If it’s not current, that doesn’t help, but probably would not cause the sensor to fail unless the oil was extremely dirty.
Oil and filter service for the 722.9 7-GTronic transmission is at every 60k miles. If it’s not current, that doesn’t help, but probably would not cause the sensor to fail unless the oil was extremely dirty.
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2010 c300
P0721 points to the output speed sensor on the conductor plate inside the transmission. The sensor can be removed and replaced, but I think it is most common to get a rebuilt conductor plate. Before going inside the transmission, check the wiring to the transmission, that the plug has not been dislodged, and that there is no oil inside the connector.
Oil and filter service for the 722.9 7-GTronic transmission is at every 60k miles. If it’s not current, that doesn’t help, but probably would not cause the sensor to fail unless the oil was extremely dirty.
Oil and filter service for the 722.9 7-GTronic transmission is at every 60k miles. If it’s not current, that doesn’t help, but probably would not cause the sensor to fail unless the oil was extremely dirty.
