One problem related to transmission solenoid has been reported for the 2007 Mazda MAZDA3. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2007 Mazda MAZDA3 based on all problems reported for the 2007 MAZDA3.
In March of 2014, while driving, the transmission popped out of gear and would only go from 2nd to 3rd gear (check engine and at light immediately came on). I brought it to my mechanic and they determined it was a failure of the solenoid a /transmission module. . . Cost me $1500. Then, 9 months later, the same thing happened. This time the mechanic said it was now the wire harness that was defective and had to repair shorted wires. . . Cost me $500. Then, 3 months later, the same thing happened. This time I brought car directly to local Mazda dealer. I asked about recall, and they said no recall! so this time I was told solenoid b had failed and I needed a new transmission. . . Cost me $1800. A week later, it did the same thing!!! I brought back to dealer and they said wires just needed tightening. A week later, my car wouldn't start. . . Needed a new starter, belts, and battery. . . Cost me $1100. This is clearly a Mazda defect and I should get my money refunded!!!.