Ford F150 Pickup. Instruction - part 1541

Fig. 304: Identifying Fuel System Circuits & Connector Terminals (Pickup - F150 Lightning 5.4L SC) 
Courtesy of FORD MOTOR CO. 

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline

  

Fig. 305: Identifying Inertia Fuel Shutoff Switch Terminals 
Courtesy of FORD MOTOR CO. 

Testing 

1) For KOEO & KOER Only DTC P0230: Check VPWR Voltage To Fuel Pump Relay 

NOTE:

On F150 Lightning 5.4L SC, Inertia Fuel Shutoff (IFS) switch relay may also be 
referred to as crash fuel shutoff relay.

NOTE:

For additional testing information, see DIAGNOSTIC AIDS.

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline

  

DTC P0230 is set when FP output is commanded ON (grounded) and excessive current draw is detected 
on FP circuit; or when FP output is commanded OFF, voltage is not detected on FP circuit (PCM expects 
VPWR voltage on FP circuit to fuel pump relay coil). Possible causes are: 

z

Open or shorted Fuel Pump (FP) circuit.  

z

Open VPWR circuit to fuel pump relay.  

z

Faulty fuel pump relay.  

z

Faulty PCM.  

Remove fuel pump relay from instrument panel relay block (F250-F550 Pickup), or battery junction box 
in engine compartment (all others). Turn ignition switch to ON position. Using a DVOM, measure 
voltage between VPWR circuit cavity at fuel pump relay connector and negative battery terminal. See 
Fig. 299-Fig. 304 . If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or less, 
repair open in VPWR circuit between PCM power relay and fuel pump relay. 

NOTE:

Two different type of relays are used for fuel pump relay. ISO micro relay 
(relay terminals are numbered 1-5) or ISO mini relay (terminals are 
numbered 30, 85, 86, 87 and 87A). On ISO micro relays, relay coil terminals 
are No. 1 and 2. On ISO mini relays, relay coil terminals are No. 85 and 86. 
See Fig. 306 or Fig. 307 .

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline

  

Fig. 306: Identifying ISO Mini Relay Terminals 
Courtesy of FORD MOTOR CO. 

 

2003 Ford Pickup F150 

2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline