Does the manager's character effect on employees workflow and commitment?

the project manager should be a role model so no doubt it does.

Yes, a manager's character has a big impact on the employees and also the image and performance of the organization.

Of course it affects

Yes it affects, good manager should has the ability to let his employees achieve the target

Yes it does , How ever it depends on the industry. For example in a Factory where the work is determined by the employees physical strength rather than mental strength there is often Negligible or no interaction with the manager regarding character or personal matter. In this case the only interaction is about timing shift details and attendance. Even if the character of Manager is bad , He can use other means like , incentives and bonus to motivate employees.On the other hand in a company where the employee is using his cognitive abilities like ( a Bank , IT company e.t.c ) The character of the Manager is Highly important and directly proportional to the employee Motivation and is In turn Directly proportional to Productivity. If the Character of Manager is bad ( Bad Mouthing , Lying , Back Biting , Nosy .. E.T.C ) No matter what motivational methods he apply , it will always be a failure. 

In any business or any organization a manager should exemplify himself a leader and a role model for his group. Doing this he gains a huge amount of respect not fear which will motivate his colleagues and reassures them that he has integrity in his actions and words.

Yes it does , the good  manager's character effect on employees workflow and commitment, and it show how much good or bad he is ,, because it is all about management at the end .