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Test B17 - FIPL Sensor

NOTE: You should perform this test when Code 23, 53 or 63 is displayed, or when directed here by other test procedure. To prevent replacement of good components, ensure the following non-EEC-IV are not at fault: idle speed and throttle stop adjustment, binding or sticking throttle shaft/linkage or speed control linkage. This circuit test is intended to diagnose only the following: FIPL sensor, sensor harness circuits and ECA.
Fig 1: FIPL Sensor Circuit
G120742
  1. Service Code 23: Checking For Stuck Throttle Plate. Visually inspect throttle linkage for binding or sticking. Ensure linkage is capable of moving freely to the fully closed position. If linkage is okay, go to next step. If not, service or replace as necessary.
  2. Service Code 53: Attempt To Set Code 63. Turn key off and wait 10 seconds. Disconnect FIPL sensor harness connector at throttle body. Inspect for damaged pins, corrosion or loose wires. Service or repair as necessary. Repeat KOEO SELF-TEST. If Code 63 is present, go to next step. If not, go to step 4). Ignore all other codes at this time.
  3. Checking Voltage At VREF To SIG RTN. Turn key off and wait 10 seconds. Disconnect FIPL sensor harness connector at throttle body. Inspect for damaged pins, corrosion or loose wires. Service or repair as necessary. Set DVOM on 20-volt scale. With KOEO, measure voltage between VREF and SIG RTN at FIPL harness connector. See Fig 1 . If voltage is 4-6 volts, go to step 9) for FIPL adjustment procedures. If not 4-6 volts, go to TEST A3 - REF  . VOLTAGE, step 1).
  4. Check FIPL Signal For Short To Power. Turn key off and wait 10 seconds. Ensure FIPL sensor harness is disconnected and DVOM is set on 200K-ohm scale. Disconnect ECA 60-pin connector. Inspect for damaged pins, corrosion or loose wires. Service or repair as necessary. Install breakout box, leaving ECA disconnected. Measure resistance between test pin No. 47 and test pins No. 26 and 57 at the breakout box. If both resistances are greater than 10k-ohms, remove breakout box, replace ECA, reconnect FIPL and repeat QUICK TEST procedure. If resistance is not greater than 10k-ohms, repair short circuit, remove breakout box, reconnect FIPL sensor and repeat QUICK TEST.
  5. Service Code 63: Attempt To Set Code 53. Turn key off and wait 10 seconds. Disconnect FIPL harness connector. Connect a jumper wire between VREF and FIPL at FIPL vehicle harness connector. Perform KOEO Self-Test. If no codes are generated, go directly to step 8). If Code 23 or 53 is present, remove jumper wire and go to step 9) for FIPL sensor adjustment procedure. If Code 23 or 53 is not present, go to next step. Ignore other codes at this time.
  6. Code 63: Checking Voltage From VREF To SIG RTN. Turn key off and wait 10 seconds. Disconnect FIPL vehicle harness connector at throttle body. Inspect for damaged pins, corrosion or loose wires. Service or repair as necessary. Set DVOM on 20-volt scale. With KOEO, measure voltage between VREF and SIG RTN at FIPL vehicle harness connector. If voltage is 4.0-6.0 volts, go to next step. If not , go to TEST A3 - REF  . VOLTAGE.
  7. Checking Continuity Of FIPL Circuit. Turn key off and wait 10 seconds. Set DVOM on 200-ohm scale and disconnect FIPL harness connector. Disconnect ECA 60-pin connector. Inspect for damaged pins, corrosion or loose wires. Service or repair as necessary. Install breakout box and connect ECA. Measure resistance between FIPL at vehicle harness connector and test pin No. 47 at the breakout box. If resistance is less than 5.0 ohms, go to next step. If not, repair open circuit and retest.
  8. Checking Resistance Of FIPL Circuit To Ground And/Or SIG RTN. Turn key off and wait 10 seconds. Disconnect FIPL harness connector. Disconnect ECA 60-pin connector. Inspect for damaged pins, corrosion or loose wires. Service or repair as necessary. Set DVOM on 200K-ohm scale. Measure resistance between FIPL at vehicle harness connector and test pin No. 46 at the breakout box and between FIPL, at vehicle harness connector, and ground. If resistance is greater than 10k ohms, remove breakout box and replace ECA. Reconnect components and retest. If resistances are not greater than 10k ohms, repair short circuit, reconnect components and retest.
  9. Checking FIPL Sensor Adjustment. Perform KOEO Self-Test with throttle in WOT position. Remain in Self-Test after last service code is displayed. Place a .515 in (13.08 mm) Rotunda Gauge Block (T83T-7B200-AH ) between the Max Throttle Travel Screw and the Gauge Boss. See Fig 2 & Fig 3 . Cycle Overdrive Cancel Switch (OCS) once. Observe Self-Test Output (STO) signal at VOM, DVOM or STAR tester. A constant signal (light or tone) indicates the signal is within range. An erratic or broken signal indicates adjustment is required.
    CAUTION: DO NOT  turn the Max Throttle Travel Screw. This screw has been preset and should not be tampered with.

    If adjustment is required, See Fig 4 . If FIPL sensor and bracket screws are tight and there are no signs of wear at any contact points, loosen FIPL sensor attachment screws and rotate sensor in either direction until a constant signal is obtained. Tighten attachment screws, remove Rotunda Gauge Block and rerun QUICK TEST.

    If bracket is loose or shows signs of wear, remove epoxy from bracket mounting screw heads. Loosen bracket screws and turn FIPL bracket assembly into adjustment range. Retighten screws and apply epoxy to screw heads. Remove gauge block and rerun QUICK TEST. If service codes are present after adjustment procedure, replace FIPL sensor.

    Fig 2: Top View of Fuel Injection Pump
    G120743
    Fig 3: Throttle Side View of Fuel Injection Pump
    G120744
    Fig 4: FIPL Side View of Fuel Injection Pump
    G120745
  10. Code 53: Monitor FIPL Circuit Under Simulated Road Shock Conditions. Enter KOEO Continuous Monitor Mode. Observe VOM or STAR LED for indication of a fault while performing the following procedures. Move throttle slowly to the WOT position. Release throttle slowly to closed position and lightly tap on FIPL sensor to simulate road shock. Wiggle FIPL harness connector. If a fault is indicated, go to next step. If a fault is not indicated, go to step 12).
  11. Measure FIPL Position Signal Voltage While Exercising FIPL Sensor. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect for damaged pins, corrosion or loose wires. Service or repair as necessary. Install breakout box and connect ECA. Ensure tester is connected to STO as in previous step. Connect a DVOM between test pins No. 46 and 47. Set DVOM on 20-volt scale. With KOEO, observe DVOM while repeating procedure in step 10). If a fault is indicated at less than 4.25 volts, disconnect and inspect connectors. If connector and terminals are okay, clear codes and go to step 9). If a fault does not occur at less than 4.25 volts, ensure harness and connectors are okay and go to next step.
  12. Check EEC-IV Harness. Ensure vehicle is still in KOEO Continuous Monitor Mode. Observe tester for a fault indication while performing wiggle test on system harness and connectors. If a fault is indicated, isolate it and repair as necessary. Clear codes and repeat QUICK TEST. If a fault is not indicated, go to next step.
  13. Checking ECA Harness and Connectors. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect for damaged pins, corrosion or loose wires. Service or repair as necessary. If connectors and terminals are okay, fault may not be duplicated at this time. Clear continuous memory codes. If a fault is found, repair as necessary, clear codes and rerun QUICK TEST.
  14. Continuous Memory Code 63: Monitor FIPL Circuit Under Simulated Road Shock. Enter KOEO Continuous Monitor mode. Observe tester while performing the following. Move throttle slowly to WOT position. Release throttle slowly to closed position and lightly tap on FIPL sensor to simulate road shock. Wiggle FIPL harness connector. If a fault is indicated, inspect connectors and clear codes. Rerun QUICK TEST and go to step 9). If a fault is not indicated, go to next step.
  15. Checking EEC-IV Harness. Ensure vehicle is still in KOEO Continuous Monitor Mode. Observe tester for a fault indication while performing wiggle test on system harness and connectors. If a fault is indicated, isolate it and repair as necessary. Clear codes and repeat QUICK TEST. If a fault is not indicated, go to next step.
  16. Checking ECA Harness and Connectors. Turn key off and wait 10 seconds. Disconnect ECA 60-pin connector. Inspect for damaged pins, corrosion or loose wires. Service or repair as necessary. If connectors and terminals are okay, fault may not be duplicated at this time. Clear continuous memory codes. If a fault is found, repair as necessary, clear codes and rerun QUICK TEST.
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