hey guys last week my car threw the check esp and spanner light up when my friend had my car he turned the car off and it never came up again until this morning on my way to work i was sitting in traffic at the lights when i looked down it came on turned the car off and it has not come back yet iv looked throught the wheels at work will inspect more tomorow but the abs wires seem ok not cuts etc brakes and fluid are ok any other ides there is this sensor pictured below with some oil / grease on it could this be the issue ? also what is this sensor for
