I have a 6.0 that recently got the clutch fan replaced (wrench light), but on the next tow weekend the light came on again going out and coming back (resets every time i shut the truck off). Took it back to the mechanic (reputable good guy) and hooked up his expensive coder and said don't worry it should be an old code related to the clutch fan. (at that time there was no light,3-4 restarts after the incident)
Going out to tow again this weekend and borrowed a OBDII reader (Inova 3030) from a coworker to see if anything comes up, but the reader instruction manual stated not to turn on the vehicle with the reader plugged in, but i'm afraid that if i shut it off the code will go away (check the other day and 0 codes).
Can i safely plug it in when the truck is running?

Thanks

 

Yes, in fact that's how readers are intended to be used.

 

My Snap-on Solus and my MT2500 not only have you turn the key on but also
start the engine depending on what test your doing. Most of the good ones will
let you data log and also watch live data.

Sean

 

You may want to study up on what folks are doing for monitoring their engine while underway, versus only after it's thrown a code.

There's a number of things that are available on the CAN BUS (the truck's information highway) that you can tap into via the ODBII port.

An inexpensive way to get both a code reader, data logger, real time monitor is, if you have an Android phone (or any inexpensive Android device, say the one Fry's has on sale for $70), download the app Torque Pro ($4.95), load in the Ford specific PIDs that come with Torque (unique device code for the different components, these being the Ford only ones). And buy a bluetooth ODBII adapter that you plug in that handy little port you're using for finding codes. Say for example the BAFX unit that sells on Amazon for $23.

There's a whole bunch of folks here running this, or a Scanguage II, or something else to get realttime data that can help you predict when things are starting to go south -- and there's a number of them with various fixes I won't get into. Watching the delta between Oil Temp and Coolant temp sounds very much like what's throwing you a CEL right now -- over 15 deg. diff with Fords latest flash and it could be telling you of an oil cooler that's clogging, just as an example. But you can also see what the fan speed is too...

 

As diesel_dan says the sg2 is great.
You can watch realtime fan speed to know whats happening. As well as oil and coolant temps to make sure your oil cooler isn't clogged.
It is essential to protect your investment in the 6L to get a monitor.
in regards to your issue, new flashes will throw a wrench lite if the oil to coolant temp exceeds 15*and which is a symptom of a clogged oil cooler.

 

I don't think it will hurt anything to plug it in with the truck running but it may have some trouble connecting. In the manual, they want the reader and the truck to power up together but it also states the reader will re-connect every few seconds so if it doesn't "catch" the first go around give it a few seconds to try again.

Once a code is set on the truck, even if the problem fixes itself, it wii stay in memory for many key on-off cycles. Some codes require a few full drive cycles to clear. So if it doesn't work to plug it in while it's running don't worry about the code clearing on it's own. It will still be there. Pressing the clear button on the reader will delete it from memory when you are ready.

Inexpensive code reader like this commonly won't pull codes for the ABS brake system, transmission, body control module, or even some manufacturer specific codes so it's possible to have a CEL and the reader show no codes.

 

You Probably Need an Oil Cooler

 

Just a thought, you can always get it scaned at auto zone , the sooner you know the better off ,have you flushed and changed thermo lately,or changed filters? what is the truck doing?besides the lite .Getting a scan tool that reads live data is a must for our trucks 160.00 at auto zone scan gaugeII

 

I also have an Inova DTC reader. It states, key off plug in reader. The reader then instructs you to turn ignition key to ON but do not start the engine. Then it reads the codes. It does this the same way with all vehicles.


If there is a code it will stay there when the engine is turned off.




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