Attention: TDR Forum Junkies 
Installed Pacbrake PRXB Direct Exhaust Kit C44045 on a 2005 Dodge Ram 2500 diesel with a G56 Manual Transmission. The installation was straight forward, no issue with compressor working and no leaks, good to go! Now ready to test the exhaust brake but it failed to work.
Per the Pac Brake manual (instructions with schematic available online), 2 wires need to be connected to the ECM 50 pin connector "B" o, located at the lower driver side
of the engine. 1. Switch: white wire to pin 39 on the ECM connector "B", Black to ground
2. Solenoid Relay: black wire to pin 42 on the ECM connector "B"
Wired to the ECM, the valve will not operate
Checks - Actions:
Corrective action solution:
Pin 39 was not making contact after the connector was installed. After thorough check of wiring of pin 42 and 39 with ohm checks and even checking the pins were installed with a
few light tugs, Pin 39 eventually came out of the connector.
Per Pacbrake's manual, you can do this install without removal of the EMC 50 pin connector or disconnecting the batteries. It is feasible, if you have an pin insert tool, without it,
you could damage the connector or break the wire from the pin; a bit risky and the access is a bit of challenge even with the fender well removed.
My recommendation is to disconnect the batteries, remove the EMC 50 pin connector, remove the rubber plugs from pin 42 & 39. Use a pin insert tool, I used an AMP insert extract
tool, I left the tool in place while reinstalling the EMC 50 pim connector. Once the connector was secured, inserted the tool into the connector to ensure pins were secured in the holes, carefully removed the insert tool and did a test pull. Now I'm confident that I have a good solid connection, real test comes next.
Reconnected the batteries, started her up, flicked on the exhaust switch; the exhaust brake works!
Pin 42 completes circuit to pin 39 thru the EMC, the EMC senses the TPS, when you turn the exhaust brake switch on, the Exhaust brake works when the TPS is at "0" or idle. When you accelerate the exhaust brake turns off.
The PacBrake worked as designed, installation error and not using the proper tools was a mistake on my part. Use of proper tools is the best way to go, double check your connections are secured.
Per the Pac Brake manual (instructions with schematic available online), 2 wires need to be connected to the ECM 50 pin connector "B" o, located at the lower driver side
of the engine. 1. Switch: white wire to pin 39 on the ECM connector "B", Black to ground
2. Solenoid Relay: black wire to pin 42 on the ECM connector "B"
Wired to the ECM, the valve will not operate
Checks - Actions:
- Both pins are fully inserted.
- Followed manual operation checks.
- Backed probed direct at the solenoid relay connector; brake works regardless of throttle position idle, accelerating or de-accelerating
- Talked to Pacbrake tech support, 2 diff techs, not able to tell me what the ECM signals are or how it works with their brake kit, what is the function from ECM
- Pac Brake suggested their ECM by-pass kit c20141, switch bracket connecting to the accelerator. Not the solution I was looking for, the truck has smarts!
- Last resort, ask the TDR Members! ECM schematic? Appreciate problem solving solutions
Corrective action solution:
Pin 39 was not making contact after the connector was installed. After thorough check of wiring of pin 42 and 39 with ohm checks and even checking the pins were installed with a
few light tugs, Pin 39 eventually came out of the connector.
Per Pacbrake's manual, you can do this install without removal of the EMC 50 pin connector or disconnecting the batteries. It is feasible, if you have an pin insert tool, without it,
you could damage the connector or break the wire from the pin; a bit risky and the access is a bit of challenge even with the fender well removed.
My recommendation is to disconnect the batteries, remove the EMC 50 pin connector, remove the rubber plugs from pin 42 & 39. Use a pin insert tool, I used an AMP insert extract
tool, I left the tool in place while reinstalling the EMC 50 pim connector. Once the connector was secured, inserted the tool into the connector to ensure pins were secured in the holes, carefully removed the insert tool and did a test pull. Now I'm confident that I have a good solid connection, real test comes next.
Reconnected the batteries, started her up, flicked on the exhaust switch; the exhaust brake works!
Pin 42 completes circuit to pin 39 thru the EMC, the EMC senses the TPS, when you turn the exhaust brake switch on, the Exhaust brake works when the TPS is at "0" or idle. When you accelerate the exhaust brake turns off.
The PacBrake worked as designed, installation error and not using the proper tools was a mistake on my part. Use of proper tools is the best way to go, double check your connections are secured.
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