DTS Common 6.0L Wiring Problems

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Common 6.0L Wiring Problems

Depicted are some of the most common wiring issues encountered on 6.0L equipped vehicles like the F-Super Duty and Econoline from 2003 and up. All of these examples show wiring chafe points and damage to body and engine harnesses that caused driveability concerns like stalling, no starts, engine misfire, PCM reset and Check Engine Light illumination. Unfortunately these types of failures are typically very difficult to diagnose because the tend to shut the engine off and leave no clues in the modules - remember what you see here.

A 6.0L injector harness laying directly atop an intake manifold bolt is never good. This one eventually wore through causing this 2004 Super Duty to stall and not restart.	After replacement of the harness we opened it up to take a look. You can clearly see the injector wire that was shorted to ground disabling the entire injection system. It does not take much.
A simple wire chafe at the EBP sensor that was caused by the harness rubbing on itself. EBP sensor wiring chafing was common on the early 6.0L in 2003 models. In that area the sensor bracket also provided a sharp edge that caused damage.	The typical FICM wiring chafe location shown with the arrow where the harness drops away from the module and bends across the edge of the valve cover or bolt head. This harness has been repaired and modified.
While this 2004 Econoline was in for repairs, this PCM body harness was found loosely laying across the edge of the PCM allowing it to vibrate and rub through. Unfortunately space in the engine compartment is limited and securing a wire harness can be challenging.	The result of this PCM body harness chafe: this purple wire was almost completely rubbed through. Note the lack of wrapping and protective tubing on the end of this harness that would have protected it from damage. Since it could not be secured it was repaired, wrapped in tape and convolute tubing was placed around the exposed end.
Accelerator wiring is typically found laying across the lower steering shaft where it sometimes rubs through. We were a little surprised to see the harness in contact with the moving parts of the pedal itself.	This is the damage that 20,000 miles of driving did to the harness. Every time the accelerator was depressed it slowly wore away at the tape and wires until the truck started running poorly due to a grounded sensor circuit.
Econoline 6.0L, again we see the unwrapped harness from the body to the PCM chafing but now on the A/C lines. This requires taping and adding convolute tubing and it is strongly recommend that you do so when ever you see this!	It is so important that when you are performing repairs or a recall on the harness that you inspect the entire harness and make effective repairs. A chafe can happen anywhere due to harness variances. Learn to observe and catch these potential problems while working on these engines.
Here is one that will become an issue with higher mileage 6.0L Econolines. The Sensor harness lays right on the rear EGR tab and bolt. This one was well on it's way to exposing wires.	6.0L Econoline, at the left fender area you will find the FICM nicely mounted. You may also find the FICM harness shorted out on the lower FICM bracket bolt. (See inset)

These photographs are shown only to provide information and to show some real life examples of what a professional technician my encounter. It is hoped that it helps technicians in identifying possible causes and assist in the quick diagnosis of identified concerns. This is not intended to replace any official instructions, authorization or documentation of any Ford Motor Company Engineers, service manual, TSB, Service Message or recall.