position. Using a DVOM, measure voltage between chassis ground and DPFEGR circuit at DPFEGR
sensor harness connector. If voltage is more than 10.5 volts, go to next step. If voltage is 10.5 volts or
less, go to step 13).
12) Check DPFEGR Circuit For Short To PWR In Harness
Turn ignition switch to OFF position. Disconnect PCM connector(s). Inspect connector for loose,
damaged or corroded terminals. Repair as necessary. Turn ignition switch to ON position. Using a
DVOM, measure voltage between negative battery terminal and DPFEGR circuit at PCM harness
connector. See PCM CONNECTOR IDENTIFICATION and Fig. 240-Fig. 242 . If voltage is more
than 10.5 volts, repair short to PWR in DPFEGR circuit. If voltage is 10.5 volts or less, replace faulty
PCM.
13) Verify Scan Tool Communication
Connect jumper wire between DPFEGR and SIG RTN circuits at the DPFEGR sensor harness connector.
See
Fig. 240
-Fig. 242 . Turn ignition switch to ON position. Using scan tool, access DPFEGR PID from
PID/DATA MONITOR & RECORD menu. If a scan tool communication concern appears with the
jumper wire connected, immediately remove jumper wire. Go to step 19). If a scan tool communication
concern does not appear with the jumper wire connected, go to next step.
14) Induce Opposite DPFEGR Sensor Voltage
With jumper wire connected between DPFEGR and SIG RTN circuits at DPFEGR sensor harness
connector, use scan tool to access DPFEGR PID from PID/DATA MONITOR & RECORD menu. If
DPFEGR PID voltage reading is .05 volt or more, disconnect jumper wire and go to step 17). If DPFEGR
PID voltage reading is less than .05 volt, disconnect jumper wire and go to next step.
15) Check VREF Voltage To DPFEGR Sensor
Turn ignition switch to ON position. Using a DVOM, measure voltage between SIG RTN and VREF
circuits at DPFEGR sensor harness connector. See
Fig. 242
-Fig. 240 . If voltage is 4-6 volts, replace
DPFEGR sensor. If voltage is not 4-6 volts, go to TEST C, step 1).
17) Check DPFEGR Circuit For Open In Harness
Turn ignition switch to OFF position. Ensure DPFEGR sensor is disconnected. Disconnect PCM
connector(s). Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Using a
DVOM, measure resistance of DPFEGR circuit between PCM harness connector and DPFEGR sensor
harness connector. See PCM CONNECTOR IDENTIFICATION and Fig. 240-Fig. 242 . If resistance
is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in DPFEGR circuit.
18) Check SIG RTN Circuit For Open In Harness
Using a DVOM, measure resistance of SIG RTN circuit between PCM harness connector and DPFEGR
sensor harness connector. If resistance is less than 5 ohms, replace PCM. If resistance is 5 ohms or more,
repair open in SIG RTN circuit.
2003 Ford Pickup F150
2003 ENGINE PERFORMANCE Self-Diagnostics - CNG, Flex-Fuel & Gasoline