7427 Efan

[CDeeZ]

Thanks Robert,

I'm going to try that method next time I boot into the Windoze side of my HDD and have access to TPRT.

Did anybody check out that hexeditor I found? Pretty neat I thought. I was easily able to open the bin, copy the Efan code into the appropriate addresses in the hex, and save a new binary!

[EagleMark]

Did you know TunerPro has a built in Hex editor? Tools, advanced, hex...

[CDeeZ]

Yes, I know TunerPro has a built in hex editor.

But like I said, I couldn't get it to work for copying and pasting the code itself into the proper addresses in the binary.

I typed it all in manually in the hex editor in TP, then went to close the hex editor, then I got: "Bin modified, Save?" clicked yes, and somehow, miraculously, it didn't save?


The point of the program I shared was that you can copy and paste the code into the hex thereby saving time. Not to mention the possibility of messing up something while transcribing the code manually one character at a time.

I could have probably spent another five minutes manually entering the code into the hex editor in TP, a second time, but doing it this way is so much easier and faster

[EagleMark]

Thanks for sharing the hex editor!

Although I try very hard not to use them, great for checking a paremeter just made though. Just me... I use the Hex all the time to find mask ID, but other then that? it's like VooDoo... I've got a lot or respect for guys that used to tune cars via hex!

[CDeeZ]

I wired up the fan to the PCM but it won't work. Followed directions exactly as prescribed in the included document file with the patch. I set the fan enable temp low to like 40 F to test if the PCM would command the fan on but it doesn't!

[CDeeZ]

Does anybody have any ideas? I recall finding a post by 93V8S10 where he talked about some of the '7427 PCMs used in HD applications had pin E3 setup differently, therefore the efan code might not work on those PCMs found in the HD applications? I can't seem to find that post at the moment.

For testing purposes, I have "Temperature for fan on" set to 80.2 and "Temperature for fan off" set to 304, this should make the PCM command the fan on all the time since ambient air temp is currently well above 80 degrees correct? Or am I doing that backwards? I'm just trying to set the fan low enough so I can test it in the driveway w/o even warming up the engine

I'm going to try the other 7427 PCM I have and maybe see about the pin difference on E3 that I recall 93V8S10 talking about.

Also, When I wiggle the wire I pinned to E3 for the E-fan, I can hear something clicking under the hood, (possibly a relay) and then the vehicle dies. I used ONE 50amp relay as I thought that would be better than stacking two 30amp relays. It is my understanding that having two 30A relays wired parallel does NOT give you the equivalent of a 60amp relay, probably more like 45amps I'd think?, and even then, during fan startup I believe there would be a moment, however slight, when the entire electrical load is going through just ONE of the 30A relays.

[RobertISaar]

you need to correct those fan settings....

think of it this way:

when the temp rises above the on-point (80*F), it wants to turn the fan on. then when the fan is on, it will turn it off once under the off-point(304*F).

can you see why it won't turn on? the off-point needs to be lower than the on-point, technical term is a hysteresis, it allows what is essentially a window of on or off operation.

also, all 7427 should the same internally, otherwise they would have a different part number.

and 2 30 amp relays WILL act similar to a 60 amp relay, assuming they are both connected well(properly sized wires, good grounding, etc), just they will have twice the current draw for the relay coil, which will be ~1/3 of an amp with 2 relays.