Ford F150 Pickup. Instruction - part 1636

2. The PCM uses CKP signal to calculate a spark target and then fires coil pack(s) to that target shown. See 

Fig. 50 . The PCM uses CMP sensor on COP Integrated EI Systems to identify top dead center of 
compression of cylinder No. 1 to synchronize firing of individual coils.  

3. The coils and coil packs receive their signal from PCM to fire at a calculated spark target. Each coil 

within pack fires 2 spark plugs at the same time. The plugs are paired so that as one fires during 
compression stroke, the other fires during exhaust stroke. The next time the coil is fired, the situation is 
reversed. The COP system fires only one spark plug per coil and only on compression stroke. PCM acts 
as an electronic switch to ground in the coil primary circuit. When the switch is closed, battery positive 
voltage (B+) applied to coil primary circuit builds a magnetic field around primary coil. When the switch 
opens, power is interrupted and primary field collapses inducing high voltage in secondary coil windings 
and the spark plug is fired. A kickback voltage spike occurs when primary field collapses and the PCM 
uses this voltage spike to generate an Ignition Diagnostic Monitor (IDM) signal. IDM communicates 
information by pulse width modulation in PCM.  

4. The PCM processes CKP signal and uses it to drive tachometer as Clean Tach Output (CTO) signal.  

Fig. 49: Identifying Integrated Electronic Ignition System Components & Circuits 
Courtesy of FORD MOTOR CO. 

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Theory & Operation - CNG, Flex-Fuel & Gasoline

  

Fig. 50: Identifying 6-Cylinder Integrated Electronic Ignition Waveforms (4, 8 & 10-Cylinder Are 
Similar) 
Courtesy of FORD MOTOR CO. 

Coil Pack System 

The EI system consists of a CKP sensor, coil pack(s), related wiring and PCM. The CKP sensor is used by PCM 
to indicate crankshaft position and speed by sensing a missing tooth on a pulse wheel mounted on front of 
crankshaft. The coil pack receives the signal from the PCM to fire at a calculated spark target. Each coil within 
the pack fires 2 spark plugs at the same time. 

The plugs are paired so one plug is fired on the compression stroke, and the other plug fires the mating cylinder, 

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Theory & Operation - CNG, Flex-Fuel & Gasoline

  

which is on the exhaust stroke. On the next cycle, firing is reversed. On 6-tower coil pack applications the 
matched cylinder pairs are: No. 1 and 5, No. 2 and 6, and No. 3 and 4. See Fig. 51 and Fig. 52 . 

On single 4-tower coil pack applications (4-cylinder), the matched cylinder pairs are No. 1 and 4, and No. 2 and 
3. See Fig. 53 and Fig. 54 . On dual 4-tower coil pack applications (8-cylinder), the matched cylinder pairs are 
No. 1 and 6, No. 3 and 5, No. 4 and 7, and No. 2 and 8. See Fig. 54 . 

The PCM acts as an electronic switch to ground in the coil primary circuit. When the switch is closed, positive 
battery voltage applied to the coil primary circuit builds a magnetic field around the primary coil. When the 
switch opens, power is interrupted and the primary field collapses inducing high voltage in the secondary coil 
winding and the spark plug is fired. 

Fig. 51: Horizontal Connector Six Tower Coil Pack 6-Cylinder Identification - Explorer, Explorer Sport, 
Explorer Sport Trac, Mountaineer & Ranger 4.0L (DOHC & OHV) 
Courtesy of FORD MOTOR CO. 

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Theory & Operation - CNG, Flex-Fuel & Gasoline

  

Fig. 52: Series 5 Six Tower Coil Pack 6-Cylinder Identification - Econoline & Pickup 4.2L, Mustang & 
Windstar 3.8L, & Ranger, Sable & Taurus 3.0L (OHV & SOHC) 
Courtesy of FORD MOTOR CO. 

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Theory & Operation - CNG, Flex-Fuel & Gasoline