Diagnostic Aids

Perform this test when instructed during QUICK TEST or if directed by other test procedures. This test is used to diagnose the following:

• Wiring harness circuits (CPP, PNP and SIG RTN).
• Faulty Clutch Pedal Position (CPP) switch.
• Faulty Park & Neutral Position (PNP) switch.
• Faulty Powertrain Control Module (PCM).

1. 1) DTC P0704 & P1709: Check CPP Or PNP Switch Function
   
   These DTCs indicate CPP or PNP switch malfunction. Possible causes are as follows:
   • Starter relay disconnected during QUICK TEST.
   • CPP or PNP switch circuit damage.
   • Faulty CPP or PNP switch.
   • Faulty Powertrain Control Module (PCM).

   Turn ignition off. Connect scan tool to Data Link Connector (DLC). Ensure shift lever is in Neutral. Turn ignition on. Using scan tool, select CPP/PNP PID. While observing CPP/PNP PID, apply and release clutch pedal. If PID value does not cycle ON and OFF, go to next step. If PID value cycles ON and OFF, check PCM connector for loose, damaged or corroded terminals. Repair as necessary. If connector is okay, replace PCM.

2. 2) Check CPP Or PNP Switch
   
   Turn ignition off. Locate CPP switch near clutch pedal or PNP switch near transmission shift linkage. Inspect switch and bracket for damage and repair as necessary. Disconnect CPP or PNP switch connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. While depressing clutch pedal, measure resistance between CPP or PNP switch terminals. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, replace CPP or PNP switch.
3. 3) Check CPP Circuit
   
   Turn ignition off. Disconnect scan tool. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Measure resistance between PCM connector pin No. 64 (CPP) and CPP/PNP terminal at CPP or PNP switch wiring harness connector. See Fig 1-Fig 4 . Also measure resistance between PCM connector pin No. 91 (SIG RTN) and SIG RTN terminal at CPP or PNP switch wiring harness connector (if applicable). If both resistance readings are less than 5 ohms, go to next step. If any resistance reading is 5 ohms or more, repair open in appropriate circuit.
4. 4) Check PNP Or CPP Circuit
   
   Measure resistance between chassis ground and PCM connector pin No. 64. Also measure resistance between PCM connector pins No. 64 and 91. If both resistance readings are more than 10,000 ohms, replace PCM. If any resistance reading is 10,000 ohms or less, repair short circuit.
5. 5) DTC P0704, P1705 & P1709: Check CPP/PNP Switch Function
   
   These DTCs indicate CPP or PNP switch malfunction. Possible causes are:
   • Starter relay disconnected during QUICK TEST.
   • CPP or PNP switch circuit damage.
   • Faulty CPP or PNP switch.
   • Faulty Powertrain Control Module (PCM).

   Turn ignition off. Ensure shift lever is in Neutral. Connect scan tool to Data Link Connector (DLC). Turn ignition on. Using scan tool, select CPP/PNP PID.

   While observing CPP/PNP PID value, perform the following:

   • Depress clutch pedal, place shift lever in gear then release clutch pedal.
   • With shift lever in gear, depress and release clutch pedal.

   If PID value does not cycle ON and OFF for both switches, go to next step. If PID value cycles ON and OFF for both switches, fault may be intermittent. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. If connector is okay, replace PCM.

6. 6) Check CPP/PNP Switches
   
   Turn ignition off. Locate CPP switch near clutch pedal and PNP switch near transmission shift linkage. Inspect both switches and brackets for damage and repair if necessary. Disconnect CPP and PNP switch connectors. Inspect connectors for loose, damaged or corroded terminals. Repair as necessary. Measure resistance between CPP switch terminals with clutch pedal depressed. Measure resistance between PNP switch terminals with shift lever in Neutral. If both resistance readings are less than 5 ohms, go to next step. If any resistance reading is 5 ohms or more, replace CPP or PNP switch.
7. 7) Check CPP/PNP Circuit
   
   Turn ignition off. Disconnect scan tool. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Measure resistance between PCM connector pin No. 64 (CPP) and CPP/PNP terminal at CPP or PNP switch wiring harness connector. Measure resistance between PCM connector pin No. 91 (SIG RTN) and SIG RTN terminal at CPP or PNP switch wiring harness connector. If both resistance readings are less than 5 ohms, go to next step. If any resistance reading is 5 ohms or more, repair open circuit.
8. 8) Check CPP/PNP Circuit For Short To SIG RTN Or Ground
   
   Measure resistance between chassis ground and PCM connector pin No. 64. Also measure resistance between PCM connector pins No. 64 and 91. If both resistance readings are more than 10,000 ohms, replace PCM. If any resistance reading is 10,000 ohms or less, repair short in appropriate circuit

Fig 1: Identifying CPP Switch Circuits & Connector Terminals (Contour & Mystique)

Courtesy of FORD MOTOR CO.

Fig 2: Identifying CPP & PNP Switch Circuits & Connector Terminals (Escort & Tracer)

Courtesy of FORD MOTOR CO.

Fig 3: Identifying CPP Switch Circuits & Connector Terminals (Econoline, Expedition & Pickup)

Courtesy of FORD MOTOR CO.

Fig 4: Identifying CPP Switch Circuits & Connector Terminals (Explorer & Ranger)

Courtesy of FORD MOTOR CO.