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ECM controlled exhaust brake on 04.5 auto?

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Pacbrake and GDP secondary fuel filter mount

P0341 Help!

As mentioned earlier, I reconnected the (TC lock up wire?) at the transmission connector. Codes went away.
1. Limp mode is gone.
2. Light on stalk switch glows when switch is pulled out.
3. It could be me and I have not driven the truck in a while but it seems to be running the more agressive shift pattern. I like it.

EB is still not turning on. I went through the Jacobs electrical troubleshooting on page 12 and 13.
Key on:
1. 10 am fuse good, 12v showing at fuse
2. disconnected EB air soleniod: 10 ohms. Should be good. Normal is 10-20 ohms
3. checked solenoid wires (solenoid disconnected): 0 volts w/ ignition and EB on. Should be reading 12 volts between wires.

Key off, remove relay base from relay, turn key back on:
Pin 30-battery 12 volts-checked 12.3 v
Pin 85-key switched 12 volts-check 12.2 v

Check continuity:
Pin 18 to Pin 42 ECM- yes
Pin 87 to solenoid- yes

Ran truck and two codes keep coming back:
P0477 Exhaust pressure control low
P0478 Exhaust pressure control high.

Maybe ECM damage resulting in those two codes?
 
IMG_8473.jpeg
IMG_8474.jpeg
 
When the wiring harness to ECM B bundle was disconnected and batteries disconnected, I checked continuity from B39 to yellow wire going to stalk switch. It was good.
 
The LED in the stalk switch is very dim, that is normal.
If all the wiring is right to your measuring you should disconnect the battery's and do a hard reset, maybe your ECM is angry about the things that happened,

And yes, the shift pattern is changed, also the TCC lockup is way more aggressive. Your TCC is most of the time locked with the EB switch On.

Maybe you fried the ECM by having voltage at Pin39 because with the simple wiring intact you shouldn't get either code.

Code 477, how it works. With the EB not active the switched 12V from the grey wire runs through the relay coil all the way into the ECM and is measured. So it wants to see 12v all the time except when the ECM ground Pin42 to activate the relay and the EB.

Code 478 is an almost impossible code as the ECM knows the voltage of the whole system and expects to see the very same voltage through Pin42.

Is your ECM properly grounded?
 
3. checked solenoid wires (solenoid disconnected): 0 volts w/ ignition and EB on. Should be reading 12 volts between wires.

What wires are we talking about here? Pin 42 and switched Positiv?
 
3. checked solenoid wires (solenoid disconnected): 0 volts w/ ignition and EB on. Should be reading 12 volts between wires.

The two wires going to the exhaust brake solenoid. C11935 pnuematic solenoid.
 
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3. checked solenoid wires (solenoid disconnected): 0 volts w/ ignition and EB on. Should be reading 12 volts between wires.

The two wires going to the exhaust brake solenoid. C11935 pnuematic solenoid.

This is wrong in the manual, this wire will only be live with the engine running and the EB active, means either cold engine or with speed.
 
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Grab a relay without a diode and try again.

And don't choose to big of a relay, just a standard one. You can even take one out of your fuse box for a try, I think there are some that aren't needed all the time.
 
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Good news!
I cleared the code (PO478)
I replaced the relay top with a Dorman 30a 4 pin relay without a diode.
I did a hard reset on the batteries: disconnected all pos and neg cables from the battery terminals and connected the pos and neg cables for 30 min.

I put it back together and started the truck. The first thing I noticed was the idle up feature working on the EB. That has not come on since I started this project. Took it for a test drive. The 4-3 shift is there, taking the speed down to 25 before cutting out. Being in the city, its hard to try for that 3-2 downshift by feathering the throttle. Too many cars in front and behind me. Slowing down for corners, I feel the EB come on at 20-25 mph (2nd?), that's new. That was a 10 minute drive and no codes (yet). So far so good. A good day. I like it.

Ozy and others, thanks for your patience and perseverance. I do appreciate it.
 
This is great news, now you can really enjoy and learn about the features.

Another one you'll figure out is driving with the cruise on.
If you drive into a downhill section, the ECM now will do a downshift (if possible) to maintain road speed if the actual gear is to high to keep it from runaway.
Don't freak out if it happens, it knows what's doing.
 
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You’re absolutely right about that part being hard to find. I found it at firsttruckparts.com. It wasn’t cheap, but I didn’t really have much of a choice.
By the way, which wire was it to tap into for the torque converter lock up indicator light? Is it the wire coming from B 39 or B 42?
 
Nope, it is the wire that was cut and you fixed it. This is the ground path for the TCC solenoid. Just follow the wire color up to the bulkhead connectors left above the hydroboost unit, two big connectors with a purple tap.
You need to tap into this for the ground of the led.
For just the LED you don't need a resistor.

Look for an 8mm LED in red that you can install on the side of the upper cigarette lighter.
 
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Thanks for the LED light info.

Also, if you know, does switching between the Smarty Jr. programs have any effect on the ECM controlled brake operation? Using the stock program currently.
 
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