2012 Hino 338 exhaust brake engages with start up

[Robin C]

Hello
This is my first time posting anything so please bear with me.
I’m an owner/operator that due to where I’m located do not have any Hino help with dealerships or not too many Hinos in my city so other techs are not too familiar with them either.
Due to this I do as much as I can on my own (I have the DX2 software) but am looking for a bit of direction with this issue.
Basically upon start up of my 2012 Hino 338 truck, the exhaust brake closes right away and in turn wants so stall the engine out. I replaced the solenoid up from the brake that controls the air to it but it didn’t change anything. My switch on the steering column whether it’s on or off always supply’s air to the brake and pushes it closed. I checked another one of my trucks (2013 338) and when you turn off the switch it stops the air to the brake piston.
I sifted thru past posts and I know you have to calibrate the brake but just wouldn’t think that’s the issue as there is air there at all time.
Any ideas/direction would be greatly appreciated.
Thanks in advance
Robin

 

[greasytshirt]

If the engine is trying to stall, the brake is closing too far. Sometimes people tamper with them in an attempt to be more effective, but it doesn't work like that.
Sometimes these trucks go into "white smoke prevention mode" if they've been left to idle for a long time. The brake immediately comes on at startup, and it takes some amount of driving to get it to stop. You might be able to disable this with DX.