Here is the info I wrote up and pasted on another site to activate the PTO idle up function on my 2004 F250 PowerStroke. This will increase the engine idle speed to 1200rpm as long as the transmission is in Park or Neutral and your foot is not on the brake pedal. NOTE: While I was a late contributor to the engine idle up article on the other website I feel my information here is more detailed explaining the actual location of the wires to be found to perform this modification.
I did this for my vehicle to try and quell any WET STACKING problems while I idle the engine for any length of time other than to cool the engine down prior to turning it off. I had some fuel in oil problems over the winter and I think this is from idling the engine for an hour at a time prior to performimg this modification.
This info is valid for 2004 PowerStrokes with the automatic transmission. I'm not sure if the manual transmission PCM's have the PTO idle up function software installed.
This procedure connects two body harness wires together with a switch. When the switch is activated battery power from one wire is sent to the PTO control wire telling the PCM to raise the idle speed to 1200rpm.
Here is what I did.
Look up under the dash between the steering column and the parking brake pedal. You will find a wiring harness behind the parking brake handle with a bunch of wires coming out of the harness that have the ends sealed off with charcoal?? colored heat shrink tubing.
If your not sure what you are looking at, look at the three wiring harnesses that come through the firewall to the left of the steering column shaft into the passenger compartment. The top harness is big, the middle harness is smaller than the top harness and the last harness closest to the floor is smaller still. The wire you are looking for comes out of the the middle harness where the harness routes up to the dash directly behind the parking brake handle.
One of these wires will be Light Blue with a Yellow stripe. This is the PTO function wire from the PCM. Placing battery power (battery positive) on this wire will command the PCM to raise the idle speed to 1200rpm as long as the transmission is in Park or Neutral and the service brake is released, meaning your foot is not on the brake pedal and the brake lights are not activated.
The other wire you are looking for is a White wire with a Light Blue stripe. This one is also easy to find. While looking under the dash direct your attention to the black OBD II datalink connector mounted to the lower part of the dash to the right of the steering column. This connector is what a service tech uses to hook up a scan tool which is needed to communicate with the vehicle PCM in order to check engine sensor data, engine trouble codes and to REFLASH your PCM. (You've heard about FLASHES haven't you???)
Anyway, look at this black connector and follow the wiring harness from the plug back up and inside the dash. Along the harness not too far up from the plug you will find the White wire with a Light Blue stripe included in the bundle of wires but the wire just stops short of the connector. Yes the wire does not plug into any one of the ports of the datalink connector.
This White wire with a Light Blue stipe is your positive battery source wire that you will connect to the Light Blue with a Yellow stripe PTO wire through a switch.
What I did was stop at Walmart's automotive section. I purchased some wire, a switch that has a Red illuminating paddle switch lever and some female crimp connectors and some butt connectors. (Note: The crimp connectors I purchased were manufactured or has 3M's name on the packaging and the plastic insulation on the connectors is heat shrinkable).
I used the wire and butt connectors to extend these vehicle wires so I could mount the switch under the dash to the right of the OBD II datalink connector. I crimped the female crimp connectors on the end of each wire so the wires could plug into the male terminals of the switch.
So far I have used two wires connected to the switch. The switch I purchased has three terminals. The last terminal is a ground connection that is used so that when the switch is turned on the switch paddle illuminates. (Note: The switch paddle lever on my switch is not bright enough to see during daylight and is dimmly lit and seen at night. Heck, with the idle speed at 1200rpm I don't think you will forget the switch is on).
I did this for my vehicle to try and quell any WET STACKING problems while I idle the engine for any length of time other than to cool the engine down prior to turning it off. I had some fuel in oil problems over the winter and I think this is from idling the engine for an hour at a time prior to performimg this modification.
This info is valid for 2004 PowerStrokes with the automatic transmission. I'm not sure if the manual transmission PCM's have the PTO idle up function software installed.
This procedure connects two body harness wires together with a switch. When the switch is activated battery power from one wire is sent to the PTO control wire telling the PCM to raise the idle speed to 1200rpm.
Here is what I did.
Look up under the dash between the steering column and the parking brake pedal. You will find a wiring harness behind the parking brake handle with a bunch of wires coming out of the harness that have the ends sealed off with charcoal?? colored heat shrink tubing.
If your not sure what you are looking at, look at the three wiring harnesses that come through the firewall to the left of the steering column shaft into the passenger compartment. The top harness is big, the middle harness is smaller than the top harness and the last harness closest to the floor is smaller still. The wire you are looking for comes out of the the middle harness where the harness routes up to the dash directly behind the parking brake handle.
One of these wires will be Light Blue with a Yellow stripe. This is the PTO function wire from the PCM. Placing battery power (battery positive) on this wire will command the PCM to raise the idle speed to 1200rpm as long as the transmission is in Park or Neutral and the service brake is released, meaning your foot is not on the brake pedal and the brake lights are not activated.
The other wire you are looking for is a White wire with a Light Blue stripe. This one is also easy to find. While looking under the dash direct your attention to the black OBD II datalink connector mounted to the lower part of the dash to the right of the steering column. This connector is what a service tech uses to hook up a scan tool which is needed to communicate with the vehicle PCM in order to check engine sensor data, engine trouble codes and to REFLASH your PCM. (You've heard about FLASHES haven't you???)
Anyway, look at this black connector and follow the wiring harness from the plug back up and inside the dash. Along the harness not too far up from the plug you will find the White wire with a Light Blue stripe included in the bundle of wires but the wire just stops short of the connector. Yes the wire does not plug into any one of the ports of the datalink connector.
This White wire with a Light Blue stipe is your positive battery source wire that you will connect to the Light Blue with a Yellow stripe PTO wire through a switch.
What I did was stop at Walmart's automotive section. I purchased some wire, a switch that has a Red illuminating paddle switch lever and some female crimp connectors and some butt connectors. (Note: The crimp connectors I purchased were manufactured or has 3M's name on the packaging and the plastic insulation on the connectors is heat shrinkable).
I used the wire and butt connectors to extend these vehicle wires so I could mount the switch under the dash to the right of the OBD II datalink connector. I crimped the female crimp connectors on the end of each wire so the wires could plug into the male terminals of the switch.
So far I have used two wires connected to the switch. The switch I purchased has three terminals. The last terminal is a ground connection that is used so that when the switch is turned on the switch paddle illuminates. (Note: The switch paddle lever on my switch is not bright enough to see during daylight and is dimmly lit and seen at night. Heck, with the idle speed at 1200rpm I don't think you will forget the switch is on).
