Detroit DDEC V jake break problum help need

[saican]

Hi Everyone,
I am having hard time with detroit DDEC V series 60 it's jake break is not coming on i checked the code there is no code i also checked all the electrical connection at solenoid and ecm connector every thing looks ok i found good continuity,cruise control working fine,i rad on one forum they was saying if the air pressure switch is not good it will not engage the jake break i was looking for this air swich could not found any where please also let me know where is this switch jake break solenoide is ok please help me to solve this problum.
Thanks

[nhatkhai]

Hi Everyone,
I am having hard time with detroit DDEC V series 60 it's jake break is not coming on i checked the code there is no code i also checked all the electrical connection at solenoid and ecm connector every thing looks ok i found good continuity,cruise control working fine,i rad on one forum they was saying if the air pressure switch is not good it will not engage the jake break i was looking for this air swich could not found any where please also let me know where is this switch jake break solenoide is ok please help me to solve this problum.
Thanks
did you check at the pedal, pull brake pedal out while driving and see if comes on, some times foot valve going out so leaves play in brake pedal, i temped one by using a bungee on pedal to leave tension.