I have a 1999 F-350. I'm in the middle of replacing the IDM off the inside of the driver's side fender and I have got a wire from the wire bundle going to the IDM but doesn't connect to anywhere. Is this a planned manufacturer option that I don't have?

 

You might want to post a pic of the wire , Ford has four wires that are call costumer use pass thru wires. You can use these for any added things like lights ect without have to fish them thru the firewall yourself. My guess is this is what you are seeing.

 

Thanks, you right. A pass through wire. I replaced the IDM and not a problem at all with the wiring. Jim

 

Did the new IDM solve your problem?

 

Yes it did. Back in buisness

 

I've got two connectors that I can't seem to find in the service manual or online. Maybe someone can tell me what they are or what they are for. The first two photos are under the steering column. When you remove the panel, the connector is mounted to the cross bar. The third photo is a connector behind the driver's side front tire splash guard. Any help with these is greatly appreciated.

 

I'm assuming your truck is a '99 based on your screen name, but that last one might be a connector for factory running board lights. I don't recall if those were an option back in '99, I know I didn't have any on my '00, but it was an XLT. Get a meter on 'em and see if it's just a power/ground (check with key on/key off/accy delay/etc).

The top two pics may be from the factory idle controller.

Those are my guesses.

 

That is the same as my 99 Ford. Doesn't connect to anything. It's by the IDM and truck runs fine without it being connected. Left it alone and tied back and out-of-the way.

 

hi im just curious as to what your symptoms were with the bad idm?,i have a 99 powerstroke that has a real hard time starting after i ran it on low batterys(alternator not charging) has good gp,good fuel pressure,eventually starts but just takes lots of cranking,is this something your truck was doing?

 

My Truck would not start at all. I ran a scan on the codes and it indicated a bad IDM. Replaced the device and I'm back in buisness. The Truck starts right up with no difficulty in cranking. Good Luck.

 

thanks,im hoping thats what my problem is too,as iv gone through absolutely everything else.

 

The connector on the knee bar under the steering column is for an Auxilary Idle Control module. The connector behind the front tire splash panels is for ABS, which was an option depending on year and trim level.

 

Thanks for the info, Greg. I looked closely at the one under the steering column yesterday, and traced it back to the harness coming from the brake controller. The harness in the back of the brake controller runs to the gray-square harness for the brake controller, but before that it splits off to run to this connector.

To comment on the hard starting Hughie O'Shea mentioned, I also recently had problems with cold start mornings. It started with the white smoke, and the starter working incredibly hard to get it going. Only 20F mornings. It got worse and worse until it stranded me and refused to turn over at all. Checked: battery voltage, battery load test, GPR, starter relay, starter lead voltage. I worried it could be alot of things, but decided to pull the starter and have it checked. It was toast. Put a brand new one in and I was blown away at the difference it made. Starts like never before, almost ridiculous.

As far as the IDM is concerned, is there a way to check the voltage the IDM gets to determine if its going bad? I know with the 6.0 the FICM gets lower than 48v for too long, it gradually wears down. I'd like to know what life mine has left.