The German was the dominant force in the opening Formula E race of the season having taken pole and leading the majority of the 37-lap contest at the Autodromo Hermanos Rodriguez circuit.
But Wehrlein, along with reigning champion Jake Dennis, were placed under investigation before the end of the race for a ‘technical infraction’ which was later revealed to be about ‘not respecting the homologated primary throttle pedal map’.
Nearly four hours after being referred to the stewards, officials decided that there would be 'no further action'.
The stewards' document read that 'after intensive investigations the Stewards couldn't find a breach of Regulations' and an 'Alleged Breach of Article 3.2.1'.
Speaking after his victory but before the stewards' decision, Wehrlein said: “The race was not an easy one, it probably looked easier than it was because I was leading almost the whole race.
“I couldn’t save a lot of energy, just always a little bit to increase my targets.
“I saw Sebastien [Buemi in second] make a mistake and it put him out of the slipstream and from then on, the race was a bit easier.
“In terms of pushing it was like a qualifying lap, just trying to maximise the corner speeds but I think this track is one of the tracks where it’s not so easy to overtake. Yes, you can overtake but you are more flat-out than some other tracks.
“I quite like the mix because at tracks like Berlin or Portland, it’s quite a bit of a mess in the beginning of the race until the pace picks up so it’s also good on the other hand that we have a couple of motor races where actually qualifying matters and you want to start in the top five.”
A 'no further action' verdict was also found regarding Dennis, meaning the Briton keeps his ninth place having made a mistake in qualifying which left him 14th on the grid.
Dennis, who races for Porsche customer team Andretti, was unaware of what the investigation was regarding immediately after the race.
Prior to the verdict, he said: “It’s nice to start the championship immediately [with a points finish], we’re on the board but two points, one point, zero points, it makes no difference.”