mrjinx

I have a 03 ram with HO 5.9 liter cummins diesel and 6 speed transmission,the techs at chrysler insalled a brand new off the shelf jacob engine break for the 03 5.9 with 6 speed transmission.Almost everything works fine except for the problem of the break not shuting off at idle or when the truck is stopped and it won't shut off when the clutch is depressed.The computor was updated,the truck had a full diagnostic to find any trouble codes,there were none.The diagnostic reading shows that the ecm has accepted the break and has no trouble codes,it shows the ecm sending messages at 165 to 175 temperature to the break also working with speed at 0 and truck at idle,we are wondering if the ecm is still the problem although it is telling us it is working.To replace it would be a big cost if that is not the problem.I am wondering if someone has ever had this problem.Thanks

Fisherguy

If the techs at Chrysler installed it shouldn't hey fix it? Maybe get them to take it off and put on a Pac Brake.

... or did they install it a long time ago?

(BTW, it's an exhaust brake)

mrjinx

Just installed it yesterday,brand new off the shelf,chrysler tech thinks it might be the ecm but is not sure and I don't want to spend money on an ecm if there is some other problem,I would like the tech to know foresure.

TDRattler

Either theres something wrong with mine or your techs are idiots. My truck has had the brake since new and its never shut off at idle or when the clutch is pressed. THey are not like the new trucks they stay on unless the go pedal is pressed.

Mlucas

TDRattler-with the brake on all the time-other than when accelerating-how does you truck idle....is it smooth, rought ect....

If it didn't shut off during clutching or idle-wouldn't that be really bad for the fuel economy?

mrjinx

I have a six speed tranny but the techs tell me that the automatics shut off automatically,if it is different with the standard tranny then what awaste of time having a jake that one has to shut off everytime you come to a stop.I know mine is a pain in the *** if you gear down and the thing is still working with the clutch in.if that is the case then jacobs needs to come up with a better system for the older trucks.I know on the 2006 and 07s that the jake works like it is supposed to.

TDRattler

First it idles fine you just here the back pressure coming through the exhaust and air cleaner. It does take extra fuel if you leave it on all time. I only use it when i tow or want to slow down going in to town or down a big hill. I have a switch like a 2 speed on the shifter so its easy to turn on and off. I wish there was a way it would work like the new one if theres a way let me know

mrjinx

I will let you know next week but I think the problem is in my clutch start interlock switch,my truck for a while has started with or with out the clutch depressed and I am hoping the ecm is confused because of it.Just a wild guess.

Utundra

Same here. On my '07 it doesn't matter whether clutch is in or out, the brake stays engaged until coolant reaches a predetermined temperature.

Quote from the Jacobs manual, "For MY2003 vehicles this temperature is around 220 degrees F; for MY2003.5 and later vehicles the temperature is around 170 degrees F."

And after reading this thread, https://www.dieseltruckresource.com/...=214507&page=2 you might not ever get to 220 degrees!

The operating and installation manuals are here, http://www.jakebrake.com/support/par...obs_product=42

carl48

the brake is working as it should they even advertised it to work this way i would never do it but you can let it idle with the brake on to warm up the engine faster, if you can get out of it i would let the dealer take it back and install a bd it will work the same way but 10x more braking power at low rpm and no vacuum pump to replace on a frequent basis