Ficm ?
- Thread starter RPM Motorsports
- Start date
simply put
it is a series of capaciters, relays, drivers, and voltage stepup transformers for the injector solenoids;
it is a series of capaciters, relays, drivers, and voltage stepup transformers for the injector solenoids;
you do not have an external FICM, from 06-present it is integrated into the Bosch ECM unlike 01-05 which uses an external FICM
Russ knows what he has
I don't doubt him:thumb: I guess I kinda worded that wrong. I was trying to figure out for shure if that was really the case as that was what I had been told. I'm just an old school lb7 guy
haven't had that much to do with the newer ones
do a search, there are some threads on here about people moving them and running coolant through them. http://www.duramaxdiesels.com/forum/showthread.php?t=14588&highlight=ficm
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Correct me if im wrong...
Think of the FICM as like what an amplifier is to some subwoofers. The PCM (stereo) gives the FICM (amplifier) the signal or input to push out to the Injectors (subwoofers). The FICM is an injector driver, takes the injector signal from the PCM, ramps up the amps/voltage needed to operate the high load injectors. Best to have all that seperated from the sensitive components inside the PCM. Plus, with it operating in such a high output, naturally theres gotta be heat buildup, so its cooled by fuel. My lift pump runs @ 15psi and it did develop a leak at the FICM. All i needed to do was tighten the case screws and it was fixed. There is also a concern where ecxessive fuel pressure can do somthing intrnally to it causing some idle issues. Mine does have a funny idle but not entirelly sure its not my FCA. I havent opened my FICM to see how its designed/see how and what might affect it. I personally wouldnt chance running it dry. It may seem cool on the outside, but thats just a case, where the circut board inside could be quite hot or some localized heating? Not sure. It was designed to be liquid cooled and with its output amps/volts i can see that.
Id like to run a whole seperate cooling system for mine. Nother project for later
Think of the FICM as like what an amplifier is to some subwoofers. The PCM (stereo) gives the FICM (amplifier) the signal or input to push out to the Injectors (subwoofers). The FICM is an injector driver, takes the injector signal from the PCM, ramps up the amps/voltage needed to operate the high load injectors. Best to have all that seperated from the sensitive components inside the PCM. Plus, with it operating in such a high output, naturally theres gotta be heat buildup, so its cooled by fuel. My lift pump runs @ 15psi and it did develop a leak at the FICM. All i needed to do was tighten the case screws and it was fixed. There is also a concern where ecxessive fuel pressure can do somthing intrnally to it causing some idle issues. Mine does have a funny idle but not entirelly sure its not my FCA. I havent opened my FICM to see how its designed/see how and what might affect it. I personally wouldnt chance running it dry. It may seem cool on the outside, but thats just a case, where the circut board inside could be quite hot or some localized heating? Not sure. It was designed to be liquid cooled and with its output amps/volts i can see that.
Id like to run a whole seperate cooling system for mine. Nother project for later
not an expert, but i would say it takes a signal from the ecm (12 volts) and bumps it up (96 volts lb7, 48 volts lly) to fire the injectors. just thinking out loud.
Correct me if im wrong...
Think of the FICM as like what an amplifier is to some subwoofers. The PCM (stereo) gives the FICM (amplifier) the signal or input to push out to the Injectors (subwoofers). The FICM is an injector driver, takes the injector signal from the PCM, ramps up the amps/voltage needed to operate the high load injectors. Best to have all that seperated from the sensitive components inside the PCM. Plus, with it operating in such a high output, naturally theres gotta be heat buildup, so its cooled by fuel. My lift pump runs @ 15psi and it did develop a leak at the FICM. All i needed to do was tighten the case screws and it was fixed. There is also a concern where ecxessive fuel pressure can do somthing intrnally to it causing some idle issues. Mine does have a funny idle but not entirelly sure its not my FCA. I havent opened my FICM to see how its designed/see how and what might affect it. I personally wouldnt chance running it dry. It may seem cool on the outside, but thats just a case, where the circut board inside could be quite hot or some localized heating? Not sure. It was designed to be liquid cooled and with its output amps/volts i can see that.
Id like to run a whole seperate cooling system for mine. Nother project for later
Spot on from what I know. It just amplifies the signal it recieves from the PCM.
I wouldn't feel very comfortable not cooling it in some way. I'm sure it develops a lot of heat. Maybe a race only truck would be fine. If you drive any distance on the street, I would make sure it get's plenty of cooling somehow.
I also find it inteseresting that these don't fail very often. I'd liked to know why and how the engineers did that. Just another thing i've been curious about.
The FICM is a "smart" voltage amplifier.
The act of amplifying any voltage introduces a time delay from the actual controlling signal depending on the rate and duration of the pulses. Of coarse, that means a timing shift which we don't want. That and keeping the output voltage within spec keeps the tiny processor in the FICM rather busy. It uses the injection pulse signals, combined with the crank signal, to adjust timing of the internal inductors, capacitors and SCRs to generate the pulse as commanded by the ECM.
The act of amplifying any voltage introduces a time delay from the actual controlling signal depending on the rate and duration of the pulses. Of coarse, that means a timing shift which we don't want. That and keeping the output voltage within spec keeps the tiny processor in the FICM rather busy. It uses the injection pulse signals, combined with the crank signal, to adjust timing of the internal inductors, capacitors and SCRs to generate the pulse as commanded by the ECM.