'03 Exhaust Brake Question

[Turbo1Ton]

Okay, I have a BD exhaust brake that I just wired up to be controlled by the ECM.



It is my understanding that the ECM will give approximately a 2 sec. delay before switching on the brake. Odd thing is that mine doesn't have this delay. Has anyone heard anything about the early '03's not having this delay?



I also read that the '03's had the programming that would turn off the brake when the temp got to a certain limit. I thought I had read that initially it was off at 210 and back on at 190 or so. They changed this later to be like 190 and 170 or something like that. Can I get a reflash in order to update this or am I stuck with the 210 temperature limit that the truck will never get to?



Thanks,



Jeff

 

[Prairie Dog]

I have one of the earliest (second shipment to dealer) trucks and mine has the delay. Not sure about the temp thing, I never leave it on that long.

Does it work rite otherwise? Any chance you have the wrong computer connection?



Scotty

 

[amsoilman]

Okay, I have a BD exhaust brake that I just wired up to be controlled by the ECM.



It is my understanding that the ECM will give approximately a 2 sec. delay before switching on the brake. Odd thing is that mine doesn't have this delay. Has anyone heard anything about the early '03's not having this delay?



I also read that the '03's had the programming that would turn off the brake when the temp got to a certain limit. I thought I had read that initially it was off at 210 and back on at 190 or so. They changed this later to be like 190 and 170 or something like that. Can I get a reflash in order to update this or am I stuck with the 210 temperature limit that the truck will never get to?



Thanks,



Jeff

I have the early 03 with a "Jacobs" E-brake, and it has the delay, but not the temperature cutout... ... ... ... ... ... ... ... ... ... ... ... ..... and I LOVE IT!



Wayne

amsoilman

 

[Turbo1Ton]

I have one of the earliest (second shipment to dealer) trucks and mine has the delay. Not sure about the temp thing, I never leave it on that long.

Does it work rite otherwise? Any chance you have the wrong computer connection?



Scotty

I doubt they are the wrong computer connections. I don't see how it would work otherwise.



It works great as far as I can tell, except for the delay deal. I don't know if mine has the temperature cutout or not because it got up to about an 1/8" above the 200 mark and never shut off.



Jeff

 

[Prairie Dog]

If I remember rite, what actually triggers the brake is just a ground (or a low) the CPU supplies to actuate the brake control relay. If that connection was always grounded the brake would never shut off. It wouldnt surprise me if many of the unused pins at the CPU are pulled down all the time like they are in many digital circuits.

Does it turn off when you shift?

 

[Turbo1Ton]

You are right there, it wouldn't surprise me either if the unused circuits were pulled down. Although I think that switching to ground on pin #39 is what tells pin #42 to pull down.



I'm not sure that I understand what you mean by does it turn off when I shift.



When I turn the switch on, the brake will engage. When I apply throttle, the brake will disengage. As soon as my foot comes off of the throttle, as the engine is actually returning to idle speed, the brake engages again. There is no delay between releasing the throttle and the engagement of the brake.



I'm positive that the brake is hooked to the correct pins (#39 and #42). I have checked that about 15 times because I was having issues with getting the brake to engage a few days ago.



Jeff

 

[Prairie Dog]

Sounds like it must be hooked up rite. I didn't write the shift question rite. I meant to ask if your sitting at a stop with the E-brake on and you drive away, does the brake engage during the short amount of time it takes to shift? If it does not engage then it's working normally.

 

[Turbo1Ton]

I'm sure you got this from the last post but yeah, the brake engages while shifting.

 

[Prairie Dog]

Thats really strange. The only way I can think of to fix it would be to get the optional clutch lockout switch assembly kit rom PacBrake and wire it into you BD setup. Let us know if your able to get it working rite some how.

Best of luck.

 

[amsoilman]

I'm sure you got this from the last post but yeah, the brake engages while shifting.

If your E-brake is working properly, you should be able to engage the E-brake at a stop, and have it come on. Then when you take off, the E-brake should disengage, and stay disengaged until you stay OFF the throttle for at least 3 seconds! IF it will NOT do this, then you have a problem.



Wayne

 

[Turbo1Ton]

If your E-brake is working properly, you should be able to engage the E-brake at a stop, and have it come on. Then when you take off, the E-brake should disengage, and stay disengaged until you stay OFF the throttle for at least 3 seconds! IF it will NOT do this, then you have a problem.



Wayne

Yeah, I have come to the conclusion that it is not working properly. Now the question is what to do about it? I mean, the brake works fine, its just that there is no delay.



So, do I spend money and have Dodge take a look at it or just say heck with it and live with it like it is? The main reason that I wanted the ECM to control the brake was for the delay. It's nice that it will work with the cruise control but I still have to switch it off when I shift. Although now that I have a shifter mounted switch, it is a lot easier than when I had the dash mounted switch, so it is not as big of a deal as it used to be.



I would have thought someone else would have had this problem. I'll do some more searching and see what I can find.



I wonder if the throttle position sensor is goofed up?



Thanks,



Jeff

 

[Phrogger57]

Temp cutout question

My recollection of the temp cutout is that the cutout function is only during warmup- if the outside temp is below a certain point (mine is 38 F), if you allow the truck to idle (cold), with the e-brake truned on , it will stay on until the eng temp reaches a certain (other )point(mine is 175). and then will kick out the e-brake. In very cold weather it will cycle the e-brake to help maintain that temp. As far as I know there is no high temp cutout for the e-brake.



As far as the delay, I agree that something is not right. I have to ask- if you engage the e-brake, does it stay on all the time, or does the throttle and/or clutch kick it off when they are touched?

-Eric

 

[Turbo1Ton]

As far as the delay, I agree that something is not right. I have to ask- if you engage the e-brake, does it stay on all the time, or does the throttle and/or clutch kick it off when they are touched?

-Eric

Sorry if I haven't been crystal clear with my descriptions. Let me give a summary.



From a stop, clutch pushed in and foot on the service brake pedal, I can switch on the exhaust brake and it will engage. I can let out the clutch and apply the throttle and the brake will disengage. As soon as I let off of the throttle to shift, the exhaust brake relay will click and immediately after the exhaust brake engages, there is no recognizable delay before the brake engages. As soon as I shift and apply throttle again, the brake disengages.



Running down the highway with the cruise control set, the brake will engage as necessary to maintain speed.



I am now really confused about the temperature thing. I have heard too many descriptions on how it should work. I'm not sure if mine works or not in that respect.



So the only issue I have seen with the exhaust brake is the lack of a delay. It is fully functional as far as I can tell except for that one feature.



Thanks,

Jeff

 

[Turbo1Ton]

I just found this in this post here: https://www.turbodieselregistry.com/forums/showthread.php?t=67723&highlight=exhaust+brake

4 - the early trucks had a 3 second delay before the computer turned on the brake..... so with the brake engaged you could shift the truck with your foot off the fuel pedal and the brake wouldn't come on..... this delay has been removed on the 03's... . This delay was a program feature of the ECM..... PacBrake has chosen to install a clutch switch to interupt the brake at the time of shifting for those of you that shift faster than the system can react.....

According to that there should be no delay on my truck. Weird.



Also found this here: https://www.turbodieselregistry.com/forums/showthread.php?t=68077&highlight=exhaust+brake

Here's the deal:



MY2003 engines: Brake will shut off at idle when coolant temperature reaches 220 degrees F.



MY2003. 5 engines: Brake will shut off at idle when coolant temperature reaches 175 degrees F.



MY2003 owners do not have to worry about this feature overheating their engines. First of all, the engine temp will probably never reach 220, just as it was with the MY98. 5 engines. Secondly, if it does reach the shut-off temperature, 220 at idle is not a concern but higher than that would be.

Looks like I should do my homework next time before posting.



Jeff