Diagnostic Aids

CID signal provides PCM information for fuel injector synchronization. The CID signal originate from Camshaft Position (CMP) sensor on 4.0L.

Enter this CIRCUIT TEST only when instructed during QUICK TEST. This test is only intended to diagnose:

• CID +, CID -, CID, SIG RTN and VREF wiring harness circuits.
• Camshaft Position (CMP) sensor.
• Crankshaft Position (CKP) sensor.
• Powertrain Control Module (PCM).

1. 1) Continuous Memory Code 214
   
   Code 214 indicates error has been detected in CID sensor input signal. Error could be due to a hard fault or an intermittent fault. Possible causes for this fault are:
   • Open or shorted wiring harness.
   • Faulty CMP sensor.
   • Faulty CKP sensor.
   • Faulty ICM.
   • Faulty PCM.

   Start engine. If engine starts, go to next step. If engine does not start, go to IGNITION SYSTEMS in SYSTEM/COMPONENT TESTS article.

2. 2) Attempt To Generate Code 214
   
   Clear continuous memory codes. Start engine. Raise engine speed to 1500 RPM for 10 seconds. Return to idle speed. Raise speed to 1500 RPM for 10 seconds again. Turn ignition off. Perform KOEO SELF-TEST. If Continuous Memory Code 214 is not present, go to step 20). If Continuous Memory Code 214 is present, go to next step.
3. 3) Check Continuity Of CID Circuits
   
   Disconnect CMP sensor (4.0L). Disconnect PCM 60-pin connector. Inspect terminals, and repair if damaged. Install EEC-IV Breakout Box (T83L-50-EEC-IV), leaving PCM disconnected. Measure resistance between CID test pin at breakout box and at CID terminal at sensor wiring harness connector. On 4.0L, also measure resistance between test pin No. 40 and PWR GND circuit at CMP sensor wiring harness connector. If either resistance is 5 ohms or more, repair open circuit and repeat QUICK TEST. If each resistance is less than 5 ohms, go to next step.
4. 4) Check CID Circuit For Short To Power
   
   Turn ignition off. Ensure PCM and CKP/CMP sensor are disconnected. Ensure scan tester is not connected to vehicle. On all models, turn ignition on. Measure voltage between CID test pin and test pin No. 40 at breakout box. If voltage is less than one volt, go to next step. If voltage is one volt or more, repair circuit short to power.
5. 5) Check CID Circuit For Short To Ground
   
   Turn ignition off. Ensure PCM and CKP/CMP sensor are disconnected. On Aerostar, measure resistance between CID test pin and test pins No. 16, 40 and 46 at breakout box. If resistance is less than 10,000 ohms, repair short circuit and repeat QUICK TEST. If resistance is more than 10,000 ohms, go to step 6).
6. 6) Check VPWR Circuit Voltage
   
   Ensure PCM and CMP are disconnected. Turn ignition on. Measure voltage between VPWR terminal at CMP sensor and negative battery terminal. If voltage is less than 10.5 volts, repair open in VREF circuit and repeat QUICK TEST. If voltage is 10.5 volts or more, go to next step.
7. 7) Check For Shorts In PCM
   
   Turn ignition off. Ensure CKP/CMP is disconnected. Connect PCM to breakout box. Measure resistance between test pin No. 24 and pins No. 37, 40, 46, 57 and 60 at breakout box. If each resistance is more than 500 ohms, go to next step. If any resistance is 500 ohms or less, replace PCM and repeat QUICK TEST.
8. 8) Check CKP/CMP Sensor Output
   
   Turn ignition off. Reconnect CKP/CMP sensor wiring harness connector. Set DVOM on AC scale. Start engine. Measure voltage between test pins No. 24 and 40 while varying engine RPM. If voltage varies more than 0.1 volt, ensure sensor is correctly installed. If sensor installation is correct, replace PCM and repeat QUICK TEST. If voltage does not vary more than 0.1 volt, replace CKP/CMP sensor and repeat QUICK TEST.
   NOTE: A break in step numbering sequence occurs at this point. Procedure skips from step 8) to step 20). No test procedures have been omitted.
9. 20) Check CID Circuit
   
   Enter wiggle test. See CONTINUOUS MONITOR MODE (WIGGLE TEST) under QUICK TEST. Observe analog VOM or diagnostic tester for indication of fault while performing following: grasp wiring harness near PCM wiring harness connector while observing VOM or diagnostic tester for fault indication. Shake and bend small sections of harness, working from PCM toward sensor. If fault is indicated, isolate fault and repair as necessary. Repeat QUICK TEST. If no fault is indicated, go to next step.
10. 21) Road Test Vehicle
    
    Purpose of this test is to identify faults by monitoring certain controlled parameters while trying to recreate a drive-ability or MIL symptom. To prepare for road test:
    • Install fuel pressure gauge and if available, a MAP/BARO tester.
    • Disconnect PCM 60-pin connector, install breakout box and reconnect PCM to breakout box.
    • Connect "T" vacuum gauge into manifold vacuum line.
    • Have DVOM, writing materials and appropriate schematics and pin voltage charts available.

    With ignition on and negative lead of DVOM connected to negative battery terminal, ensure following signals are correct:

    • POWERS: KAPWR (pin No. 1) is greater than 10.5 volts, VPWR pins No. 37 and 57) is greater than 10.5 volts and VREF (pin No. 26) is 4-6 volts.
    • GROUNDS: PWR GND (pins No. 40 and 60), SIG RTN (pin No. 46) and IGN GND (pin No. 16) are 0.0-0.5 volt.
    • OPTIONAL GROUNDS: HO2S GND (pin No. 49), CSE GND (pin No. 20) and MAF RTN (pin No. 9 or 15) are 0.0-0.5 volt.

Drive vehicle and attempt to induce symptom. Information provided by vehicle operator may help when trying to recreate symptom. When symptom occurs, assistant should observe and record changes in voltage signals. Information about symptom and operating condition value of voltage signal and any other information available should be recorded for analysis. If unable to duplicate symptom during road test, verify EEC-IV values are within acceptable range. After test is completed, analyze results to locate and repair fault causing symptom. If problem cannot be identified, go to TESTS W/O CODES article in this section for other possible causes of symptom.